Articles for category Promoting young researchers

In May, Canadian Robert William Pfeffer, great-grandson of eminent plant scientist Wilhelm Pfeffer, visited the places in Leipzig, Germany, where the namesake of the Wilhelm Pfeffer Foundation had conducted his research at the turn of the 19^th century. Robert William Pfeffer and his wife Martha Pfeffer presented a generous donation of 10,000 Euros to support the goals of the DBG's own foundation, which honors early-career plant scientists for outstanding research achievements. The foundation alternately awards the Wilhelm Pfeffer Prize for a Ph.D. thesis and the Prize for the Best Plant Science publication.

For their study published in the journal Science on the genetic basis of the biosynthesis of gramine, a toxic alkaloid in barley, the three first authors receive this year's Prize for the Best Plant Science Publication. The prize, awarded by the Wilhelm Pfeffer Foundation of our German Society for Plant Sciences and endowed with 1,000 euros, goes in equal parts to:  

• Sara Leite Dias from the Leibniz Institute of Plant Genetics and Crop Plant Research in Gatersleben (IPK), to
• Dr. Ling Chuang during the study at the Leibniz University Hannover (now at the Max-Planck-Institute for chemical ecology), and to
• Shenyu Liu, also from Leibniz University Hannover. 

"The discovery of the key enzyme for the production of gramine completes our knowledge of its biosynthetic pathway and holds the potential for numerous applications in plant breeding and agriculture. In addition, the enzymatic mechanism for creating a new carbon-nitrogen bond is also quite unusual,“ Prof. Severin Sasso, president of the Wilhelm Pfeffer Foundation, explains the award for this Science study entitled 'Biosynthesis of the allelopathic alkaloid gramine in barley by a cryptic oxidative rearrangement'. The elucidation of gramine biosynthesis also enables its production in other organisms that cannot synthesize gramine themselves, as the authors have shown for the model plant Arabidopsis thaliana or the yeast Saccharomyces cerevisiae. The new results also provide a basis for the breeding of improved barley varieties that are more resistant to herbivores, fungi and bacteria in the future and thus make a contribution to sustainable pest control. At the same time, the existing toxicity of barley for ruminants can be reduced in the future.

More on DBG's awards for early career plant scientists:

In the past year 18 authors of master theses received awards for their excellent research in the plant sciences. The topics for example were development, establishment or verification of new methods or techniques, analysis of metabolic pathways and biosynthesis, or addressing impacts of climate change. The studies also addressed plant pathogen defence, plant-microbe-interactions, functional characterizations, seed dispersal, enzyme studies, stress reactions, quality of seeds, or water balance. Thanks to the help of our contact persons DBG was able to award these prizes for the tenth year in a row at the participating universities.

The participants voted for the ten best out of the almost 400 science posters presented at the Botanik-Tagung, International Conference of the German Society for Plant Sciences (DBG). DBG’s awardees will receive 142 Euros each, since DBG was founded 142 years ago. The list with the names of first authors and the titles of the awarded posters, as well as single photos of each of the hand-overs of the certificates are summarized here:

During the International Conference of our German Society for Plant Sciences (DBG) the Botanik-Tagung, plant geneticist Dr. Henryk Straube received the Wilhelm Pfeffer Pize, microbe scientist Dr. Eliza Loo got the Eduard Strasburger Prize, and bioinformatician Dr. Martin Lewinski’s work was awarded with the Horst Wiehe Prize. The three awardees were invited to present their research in a plenary lecture. Also cell biologist Dr. Pratibha Kumari was handed over the certificate for the best plant science paper, awarded in 2023, during DBG’s biannual science conference. Their excellent plant research results will help future research in measuring rare DNA nucleotids, improving plant health, analyzing RNA binding proteins, or looking into plant cell division.
Details about this year’s science awards can be retrieved from the press release published beforehand: “Roots are like human guts, new enzyme discovered, and new lab method established”.

Registration is open for DBG's second Eduard Strasburger Hot Topic Workshop. It focusses on "Co- and posttranslational control in chloroplasts" (#DBGHotTop2024) and will be organized in Münster, Germany, from 18 – 20 November 2024. Attendance to the workshop is free for early career researchers (ECRs) and made possible through DBG's funding. The workshop will be organised by Dr Jürgen Eirich and Jens Mühlenbeck from the Institute for Plant Biology and Biotechnology at Münster University.

The next Eduard Strasburger Hot Topic Conference will focus on “Co- and posttranslational control in chloroplasts” in Münster, Germany, from 18 – 20 November 2024. It will be organized especially for early career researchers (ECR), who will be invited to join the meeting without any fees. Some of well-known speakers in this field have already confirmed their participation, according to the organizers Dr. Jürgen Eirich and Jens Mühlenbeck from the Institute for Plant Biology and Biotechnology at Münster University. Stay tuned for more information to come.  

The nominations for the three prestigious awards for aspiring early career plant scientists are open now. DBG members and others, please nominate suitable candidates for the Eduard Strasburger Prize, the Wilhelm Pfeffer Prize and the Horst Wiehe Prize. Also read "Übersicht der Wissenschaftspreise der DBG". Application deadline is 1^st May 2024 for each of them.

Summary table (in German, pdf)

Update 08 April 2024: all 60 grants have already be allocated.

To support participation of early career plant scientists (ERC) in our International Conference of the German Society for Plant Sciences (BT2024: Botanik-Tagung 2024 15^th to 19^th September 2024 in Halle a.d.S., Germany), DBG provides a maximum of 60 travel grants up to 400 Euro each for members, who actively take part in the conference with a talk or a poster. DBG reimburses traveling and accommodation costs as well as registration fees. Grants will be allocated according to the order in which applications are received; until 25^th May the latest. It therefore is advantageous to apply rapidly.

Details are in our intranet (login required)

The topics in the master theses ranged from parasite defence over a hands-on model for teaching, an interactive database to help people protecting endangered plants, the search for resistances in crops up to the effects of microplastics as well as drought stress, just to name a few. They received the prizes for best master theses which were awarded by DBG last year. The 18 awards at the participating universities were given to eight female and ten male students for their excellent studies. The following summary provides their names and research details.

To list of awardees and research topics

In 2022 DBG has awarded 15 early career plant scientists and their outstanding master theses. The diverse range of topics included research results that were published in a Nature article. The many topics covered: nickel resistance in a Noccaea caerulescens infecting pathogene, genetic markers to identify the alga Pantocsekiella, ER-tonoplast membrane contact sites, whether some endemic Euphorbia species resulted from polyploidisation, Glyoxalase I among Arabidopsis thaliana ecotypes, how Galium wirtgenii adapts to restored meadows, how heat and nitrogen amounts influence growth and development of potato plants, invention of an in vivo NADH/NAD+-monitoring system in pattern-triggered immune response, how N-deficiency in Helianthus annuus induces UV-screening compounds, a new electro-physiologic method to characterize the PIN-FORMED8 transport protein, how stomatal morphology impacts gas exchange, transcriptional control of photosynthetic gene expression, how lipids regulate the membrane-actin interface in polar growing plant cells, antibacterial gene silencing approaches, as well as mesofauna biodiversity in tree cavity habitats.
The DBG warmly congratulates the successful award winners and thanks the contact persons who managed the selection process at the individual universities and handed over the certificates.

Names of the awardees and contents of awarded theses

From the more than 300 displayed scientific posters presented at Botanik-Tagung 2022, International Conference of the German Society for Plant Sciences, participants and a jury selected the ten best posters in a two-step selection procedure. Votes from participants were given priority over committee votes. The early career plant scientists were rewarded for their scientific work presented on the respective posters and received an endowment of 140 Euros reach, since our German Society for Plant Sciences (DBG) has turned 140 this year.

Awarded early career scientists and the titles of the presented posters (pdf file)

DBG offers travel grants for early career scientists, who want to visit another lab / institute for example to leanr new methods and scientific techniques or to initiate pilot studies with up to 400 Euros each. 

> application process

> payment of grants

> online application form

BT22: Application for Travel Grants

The DBG supports young scientists actively taking part in the Botanik-Tagung (28 August to 1 September 2022 in Bonn, Germany) and provides a maximum of 100 travel grants up to 350 Euros for early career participants.

Requirements

• You must be a member of the DBG (membership applications are possible any time; become a member)
• You are a young scientist doing a PhD or writing your Master thesis without holding a full position
• You are working on a topic of plant science
• You are presenting a poster or giving a (short) oral presentation
• You provide evidence of your expenses with receipts after the conference
• Multiple financial support is excluded

Application

Please complete the > application form, which will be transmitted to the treasurer of the DBG. You will receive a notice afterwards.

Deadline

Please submit your application for a travel grant (read details here) until 24^th May 2022 the latest. The travel grants to visit the Botanik-Tagung, International Conference of the German Society for Plant Sciences (in Bonn, Germany, 28 August to 1 September 2022), will be allocated according to the order in which applications are received. Being fast therefore is of advantage.

Decision

You will receive an e-mail regarding the approval of your travel grant application.

Reimbursements

Traveling Costs

DBG reimburses either a second-class train or bus ticket or it covers the travel allowance for car usage.

Accommodation Costs

The DBG reimburses accommodation costs not exceeding the maximum of the legally established levels of the tax office.

Registration fee

The DBG reimburses registration fee.

> Application form

> Reimbursement  

16 excellent Master theses in the plant sciences were awarded by our Society in the preceding year. The awarded persons (twelve female and four male scientists) did research in the following topics and questions:  

At which site parasites infect host plants; how plant defence strategies against pathogenic bacteria evolved; plant-microbe interactions; evolution of C3-C4 intermediate photosynthesis; localization of membrane transport proteins; genetic structure of allopolyploid marsh orchids; karyotype evolution in sugar beet; role of cyclophilin in the redox regulatory network; status of the threatened plant Sand Silvercrack; terpene biosynthesis in cyanobacteria; functional characterization of enzymes involved in violaxanthin biosynthesis; pathogen hypersusceptibility and defence in Arabidopsis suppressor mutants; localization analysis of enzymes involved in Lewis a-epitope formation; glutaredoxins as well as habitat requirements of alpine tussock graminoids.

The prizes, which have been awarded for eight years in a row by now, are supported by a certificate and a financial appreciation and were coordinated at the participating universities thanks to DBG’s local representatives. DBG congratulates all awardees, thanks the contact persons involved and wishes all awardees success in their further careers.  

All awardees’ names and titles of the master theses are listed here

Sorry, in German only

Auch wenn  die Verleihungen und die Übergabe der Urkunden dieses Jahr Pandemie-bedingt auf Distanz und nicht bei Abschlussfeiern stattfanden, konnte die DBG wieder mehrere herausragende Master-Abschlussarbeiten in den Pflanzenwissenschaften auszeichnen. Die vielfältigen Arbeiten aus den 12 Hochschulen, von denen die DBG Mitteilungen erhielt, thematisierten: 

• CAM-Photosynthese und physiologische Charakteristika
• Pflanzenmerkmale und Attraktivität für bestäubende Insekten
• wie eine Glykosilierung die Geißel-Bewegung beeinflusst
• Evolution der RNA im Moos Physcomitrium patens
• Tetrapyrrol-Synthese
• in vivo-Analyse der Protein Translokation in Peroxisomen
• physiologische Stressantwort in Synechocystis
• neue Modellorganismen zur Erforschung der frühen Landpflanzen-Evolution
• wie Genom-Duplikationen und wiederkehrende Hybridisierung die Artbildung beeinflusst
• zwei neue Methoden: neu etabliertes optogenetisches System, Genom-Editierung mittels CRISPR/Cas9 in der Grünalge Volvox carteri
• wie man kontinuierlich Wasserstoff produzieren könnte, wenn man verschiedene Organismen geschickt miteinander kombiniert.

Die DBG dank den Kontaktpersonen an den Universitäten, für Ihr Engagement bei der Auswahl der besten Master-Arbeiten des vergangenen Jahres, die in diesem Jahr mehrheitlich an weibliche Forschende verliehen wurden.

Zu den Titeln, Preisträger*innen, Bildern und Abstracts

Sorry, report in German only

Ihre Ergebnisse und Forschungsarbeiten über die vielfältigen Interaktionen zwischen (Nutz-)Pflanzen und Mikroben tauschten knapp 20 angehende Wissenschaftler*innen aus drei Ländern im Februar in Königswinter aus. Die Tagung thematisierte sowohl Symbiosen als auch Pflanzen-Pathogene. Eine externe Vortragende berichtete über Jobs außerhalb von Universtäten und ein Mitmach-Workshop ermunterte die Teilnehmenden über Chancen und Risiken der öffentlichen Kommunikation ihrer Forschungsthemen nachzudenken. Einig war man sich, dass es ein großes Interesse an der Interaktions-Forschung geben sollte, da diese dazu beiträgt, anwenderfreundliche Lösungen für den Erhalt der Pflanzengesundheit und der Ertragsmengen zu bieten. Die fünf Organisator*innen des Eduard-Strasburger-Workshops der DBG von angehenden Nachwuchskräften der Sektion für Interaktionen für andere junge Pflanzenwissenschaftler*innen fassen die Veranstaltung zusammen.

Robert Hoffie, who tweets as @ForscherRobert on Twitter received the Section's first award for excellent science communication on 13th February 2020.

Sorry, futher details available in German only.

Erstmals haben wir unseren neuen Preis für Wissenschaftskommunikation verliehen. Die Auszeichnung ging an Robert Hoffie, Doktorand am Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung in Gatersleben (IPK). Als @ForscherRobert engagiert sich der Pflanzenforscher in Sozialen Medien, erklärt geduldig den Stand der Forschung über moderne Methoden in der Pflanzenforschung und scheut - wenn es nötig ist - auch nicht die Auseinandersetzung mit Politikern.
„Wenige andere Pflanzenwissenschaftler sind so engagiert in den sozialen Netzwerken wie Robert Hoffie“, sagte Prof. Dr. Stefan Rensing, Sprecher der Sektion. Er wünsche sich mehr Wissenschaftler wie Robert Hoffie, die unsere Themen in die Öffentlichkeit tragen und unsere Sichtbarkeit erhöhen.

Die Auszeichnung verlieh die Sektion am 13. Februar, während der jährlichen Konferenz Molecular Biology of Plants in Dabringhausen (Nordrhein-Westfalen). „Der Preis ist für mich Motivation und Bestätigung zugleich“, erklärte Robert Hoffie. Denn der aktuelle Stand der Wissenschaft sei das Beste, was wir haben, um zu fundierten Einschätzungen zu kommen. "Worauf, wenn nicht darauf, sollen wir unsere Einschätzungen denn künftig sonst stützen?“ fragt sich der 28-Jährige. Zwar könne die Wissenschaft nicht die Politik ersetzen, werde aber selbst immer mehr zu einem gesellschaftlichen Akteur.

Quelle: IPK beim idw

Temperature regulation in tree canopies, heavy metals and herbivory, speciation, development of fluorescent sensors for hypoxia investigations, a phytopararetrovirus of sugar beet, (bio-)synthesis and chemistry of suberin and leucine, as well as the development of orchards in the city were topics of the ten awarded master theses, which were given DBG's awards for best plant science master theses in 2019. The work was carried out at the universities of Bayreuth, Bielefeld, Bonn, Dresden, Cologne, Leipzig, Münster, Oldenburg, Rostock, Salzburg, and the Karlsruher Institut für Technologie. DBG thanks all involved jury members at the universities.

​read more about all 10 awarded theses

From the more than 190 posters presented at Botanikertagung 2019 in Rostock, Germany, participants chose several as best papers. The awarded presenters received a document as well as 137 Euros each since the German Society for Plant Sciences (DBG) today was 137 years old.

Awarded young scientists and their poster titles (pdf file)

How climate change influences growing seasons length in woody plants and survival of flowers, the substances that influence shape changes of plastids, and the proteins that spur phloem differentiation are in the research focus of the four plant scientists who will receive the science prices of the German Society for Plant Sciences (DBG) this year. Dr. Constantin Mario Zohner, Dr. Jessica Lee Erickson, Dr. Moisés Expósito Alonso and Dr. Eva-Sophie Wallner will get their awards during the Botanikertagung, the International Plant Science Conference in Rostock, Germany. From 16^th to 18^th September, the four will present their research results to the more than 420 conference participants.

How climate change influences growing seasons length in woody plants and survival of flowers, the substances that influence shape changes of plastids, and the proteins that spur phloem differentiation are in the research focus of the four plant scientists who will receive the science prices of the German Society for Plant Sciences (DBG) this year. Dr. Constantin Mario Zohner, Dr. Jessica Lee Erickson, Dr. Moisés Expósito Alonso and Dr. Eva-Sophie Wallner will get their awards during the Botanikertagung, the International Plant Science Conference in Rostock, Germany. From 16^th to 18^th September, the four will present their research results to the more than 420 conference participants.

Members, especially early career plant scientists, can receive funding for visiting another lab or institute. For example to leant new methods and  scientific techniques or to initiate a new pilot study. Funding is restricted to those who will not receive funding elsewhere. DBG offers up to 50 travel grants each year for early career plant scientists of up to 400 Euros each. Our Executive Board reviews the applications and gives you feedback about its decision (normally within one week).

DBG invites members - especially early career researchers (ECRs) - to submit proposals for a "hot topic" conference in the plant sciences. If you have a concept for a smaller conference about a relevant and burning plant science issue, please send it to DBG's Executive Board. Within the scope of our Eduard Strasburger Workshop DBG offers financial support for its organisation of up to 10,000 Euros.

Important Criteria for a Successful Application are

1. a topic with broad scientific or societal significance
2. the topic that encompasses several plant science disciplines
3. participation of early career scientists

If either (1) or (2) of the criteria on one hand and (3) on the other hand are met, please send your proposal to DBG's General Secretary. You are welcome to send a preliminary inquiry on your issue to our General Secretary.

Application and Procedure

Application

Applications for our Eduard Strasburger Workshop on a Hot Topic may be submitted to DBG's General Secretary at any time.

Application Documents

Please study our application and documentation form (pdf)

50 Travel Grants for a Lab Visit

DBG offers travel grants for early career scientists, who want to visit another lab / institute for example to leanr new methods and scientific techniques or to initiate pilot studies with up to 400 Euros each. 

> application process

> payment of grants

> online application form

DBG offers travel grants for early career scientists, who want to visit another lab / institute for example to leanr new methods and scientific techniques or to initiate pilot studies with up to 400 Euros each. 

> application process

> payment of grants

> online application form

The nominations for the three prestigious awards for aspiring early career plant scientists are open now. DBG members and others, please nominate suitable candidates for the Eduard Strasburger Prize, the Wilhelm Pfeffer Prize and the Horst Wiehe Prize.

Summary: table (pdf, in German)

The DBG awards the two young plant scientists Dr. Aleksandra Sapala (MPI for Plant Breeding Research Cologne, Dr. Richard Smith at Prof. Miltos Tsiantis) and Dr. Jutta Baldauf (Bonn University, Prof. Frank Hochholdinger) with its Best Paper Prize. Sapala has shown why plants have puzzle cells, how this shape emerges and what advantages they provide for the plant. In the journal eLife (DOI: 10.7554/eLife.32794) she also demonstrates that in plants physics play just an important role as biochemistry or genetics. Baldauf described extensive gene expression complementation in maize hybrids driven by evolutionary younger non-syntenic genes in the journal Current Biology (DOI: 10.1016/j.cub.2017.12.027). These SPE genes could be used to identify high-yield plants. Both awardees will receive their certificates next year during the Conference Botanikertagung in Rostock, Germany. The financial endowments were already presented to them.

Read more about DBG’s support of young scientists

The DBG awarded the two scientists Dr. Katja Meyer (Bielefeld University, WG Prof. D. Staiger) and Dr. Max Lauterbach (Mainz University, WG Prof. G. Kadereit, now Australia) with the Best Paper Prize in Plant Sciences 2018. Meyer adapted the iCLIP technique for plants and identified numerous rhythmic transcripts to be directly regulated by the clock-controlled RNA-binding protein AtGRP7. She published the results in the Journal Genome Biology (DOI: 10.1186/s13059-017-1332-x). Lauterbach identified genes putatively encoding novel C4 proteins through a comparison of five chenopod species with different photosynthetic types. He published the results in the journal Frontiers in Plant Science (DOI: 10.3389/fpls.2017.01939). The awardees will receive their certificates next year during the Conference Botanikertagung in Rostock, Germany. The financial endowments were already given to them.

Read more about DBG’s support of young scientists

Linda Titkemeier's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Carl von Ossietzky Universität Oldenburg in the year 2017

Title of awarded thesis

"Development of suitable supports for plant specification courses.
A research on German High School and college students to determine their knowledge of native plants, their diversity and growth."

This research is the first to compare the knowledge of Biology college students before and after taking part in a plant specification course and the first to take a focus on how to further improve study supports.

The final programme for the Eduard-Strasburger Workshop of the DBG is ready and lists speakers and titles of the talks. The paper also informs about the venue and public transportation. The conference will take place in Bonn, Germany, from 17^th to 19^th April 2018. Orgnizers Dr. Stefanie Müller-Schüssele und Dr. Mareike Schallenberg-Rüdinger are looking forward to an interesting meeting.

> Programme (pdf)

The final programme for the Eduard-Strasburger Workshop of the DBG is ready and lists speakers and titles of the talks. The paper also informs about the venue and public transportation. The conference will take place in Bonn, Germany, from 17^th to 19^th April 2018. Orgnizers Dr. Stefanie Müller-Schüssele und Dr. Mareike Schallenberg-Rüdinger are looking forward to an interesting meeting.

> Programme (pdf)

From 17^th to 19^th April early career plant scientists will meet to discuss research on mitochondria at Bonn University under the title Power Plants in Plants – Mitochondrial Functions in the Green Lineage. Interested people are invited to register until 10^th March 2018. The Eduard-Strasburger Workshop funded by the DBG is organised by Dr. Stefanie Müller-Schüssele und Dr. Mareike Schallenberg-Rüdinger who look forward to an interesting meeting, which will allow early careers scientists to meet, network and discuss their recent results.

> Poster: speakers and schedule (pdf file)

> Registration Form (Word .dotx file)

> Venue: Bonn University, Institute for Cellular and Molecular Biology (IZMB), Kirschallee 1, 53115 Bonn, Germany

From 17^th to 19^th April early career plant scientists will meet to discuss research on mitochondria at Bonn University under the title Power Plants in Plants – Mitochondrial Functions in the Green Lineage. Interested people are invited to register until 10^th March 2018. The Eduard-Strasburger Workshop funded by the DBG is organised by Dr. Stefanie Müller-Schüssele und Dr. Mareike Schallenberg-Rüdinger who look forward to an interesting meeting, which will allow early careers scientists to meet, network and discuss their recent results.

> Poster: speakers and schedule (pdf file)

> Registration Form (Word .dotx file)

> Venue: Bonn University, Institute for Cellular and Molecular Biology (IZMB), Kirschallee 1, 53115 Bonn, Germany

Why an invasive pest slug devoured some lettuces while others remain untouched was one of the topics of the honoured master theses (little hint: it were not the salads themselves). The other young plant scientists elucidated specific functions of N-glycosylated proteins in plants, analysed the effects of inhibited chloroplast's development on genetic expression, tested, which substances of an invasive plant contributed to substantial crop failure. One thesis clarified three algal taxa of Trachelomonas, that were validly described already 100 years ago. For the fourth time the German Society for Plant Sciences (DBG) has awarded outstanding MSc theses. This year they were given to three female and two male biologists from the universities of Bielefeld, Münster, Salzburg, Kiel as well as LMU in Munich. The summaries and images of the outstanding works are now on the website.  

See overview

Why an invasive pest slug devoured some lettuces while others remain untouched was one of the topics of the honoured master theses (little hint: it were not the salads themselves). The other young plant scientists elucidated specific functions of N-glycosylated proteins in plants, analysed the effects of inhibited chloroplast's development on genetic expression, tested, which substances of an invasive plant contributed to substantial crop failure. One thesis clarified three algal taxa of Trachelomonas, that were validly described already 100 years ago. For the fourth time the German Society for Plant Sciences (DBG) has awarded outstanding MSc theses. This year they were given to three female and two male biologists from the universities of Bielefeld, Münster, Salzburg, Kiel as well as LMU in Munich. The summaries and images of the outstanding works are now on the website.  
See overview

Sorry, in German only

Der 3. Eduard Strasburger Workshop mit dem Titel Two Genomes in one Cell - Communication and Conflict lockte mehr als 40 Wissenschaftlerinnen und Wissenschaftler der Polyploidie- und Hybridisierungsforschung nach Bremen. Dort thematisierten sie, welche Schwierigkeiten Zellen meistern, die ihre Chromosomensätze mischen oder gar vervielfältigen. Der Workshop fand vom 30. August und 1. September 2017 statt unter der Regie der Nachwuchswissenschaftler Dawit Girma Tekleyohans, Niklas Buhk und Thomas Nakel der Universitäten Oldenburg und Bremen. Die vorwiegend jungen Nachwuchskräfte reisten aus mehreren Nationen an, darunter Deutschland, Österreich, Schweiz, Schweden und Pakistan, was die internationale Relevanz des Themas unterstreicht. Die Organisatoren berichten in ihrer Tagungsnachlese unter anderem über neue Modellpflanzen, einen Genomschock, eine Methode zum Nachweis von drei Eltern und in welcher Weise junge Forschende bevorzugt wurden.

From the 235 posters presented at Botanikertagung 2017 in Kiel an expert jury chose several as best papers. The awarded presenters received a document as well as 135 Euros each since the German Society for Plant Sciences (DBG) today was 135 years old.

Awarded young scientists and their posters (pdf file):

This summer, young plant scientists will focus on Two genomes in one cell - communication and conflict. From August 30 until September 1, 2017, they will come together in Bremen in the 3rd Eduard Strasburger Workshop. The Workshop supported by the DBG brings together young and senior plant scientists and opens a forum for talks and discussions as well as for networking. Registration deadline for the popular workshop that will be organized by young scientists from the Universities of Bremen and Oldenburg (Dr. Dawit Girma Tekleyohans, M.Sc. Thomas Nakel, M.Sc. Niklas Buhk) is on July, 31.

> Poster (pdf file)

> Invitation and topic (pdf file)

> Registration (pdf file)

> details on website: http://www.uni-bremen.de/en/molgen/strasburger-2017.html">http://www.uni-bremen.de/en/molgen/strasburger-2017.html

This summer, young plant scientists will focus on Two genomes in one cell - communication and conflict. From August 30 until September 1, 2017, they will come together in Bremen in the 3rd Eduard Strasburger Workshop. The Workshop supported by the DBG brings together young and senior plant scientists and opens a forum for talks and discussions as well as for networking. Registration deadline for the popular workshop that will be organized by young scientists from the Universities of Bremen and Oldenburg (Dr. Dawit Girma Tekleyohans, M.Sc. Thomas Nakel, M.Sc. Niklas Buhk) is on July, 31.

> Poster (pdf file)

> Invitation and topic (pdf file)

> Registration (pdf file)

> details on website: http://www.uni-bremen.de/en/molgen/strasburger-2017.html">http://www.uni-bremen.de/en/molgen/strasburger-2017.html

The society supports young scientists in granting travel allowances for members of the DBG who participate at the Botanikertagung by presenting an oral paper or a poster (author or coauthor). The international Botanikertagung will take place in Freising Weihenstephan from August 30th to September 3rd, 2015. It will be provided either for students / graduates or for young researchers who lack a full salary.

Travel allowances and application: Details and Application Form (Intranet)

> become a member of the DBG first

The society supports young scientists in granting travel allowances for members of the DBG who participate at the Botanikertagung by presenting an oral paper or a poster (author or coauthor). The international Botanikertagung will take place in Freising Weihenstephan from August 30th to September 3rd, 2015. It will be provided either for students / graduates or for young researchers who lack a full salary.

Travel allowances and application: Details and Application Form (Intranet)

> become a member of the DBG first

Sorry - in German only:

Von Nachwuchswissenschaftlern für Nachwuchswissenschaftler

Wenn Sie Postdoc oder Doktorand sind, eine Idee für einen Workshop über eine aktuelle pflanzenwissenschaftliche Thematik mit interdisziplinären Ansätzen haben und eine Plattform für einen lebendigen Austausch von Doktoranden untereinander veranstalten möchten, schicken Sie Ihr Konzept bitte an den Vorstand der DBG, der Ihre Veranstaltung im Rahmen eines Eduard Strasburger-Workshops mit bis zu 5.000 € unterstützt. Bitte wenden Sie sich jederzeit an den Präsidenten der DBG. Der zweite Eduard Strasburger-Workshop fand im September 2016in München statt und hatte den Titel "Phylogenomics - The next generation of evolutionary botany". In ihrer Tagungsnachlese thematisieren die Organisatorinnen Susann Wicke und Dörte Harpke nicht nur die Tagungsschwerpunkte sondern auch die Sorgen der Nachwuchskräfte.

Details im aktuellen Ausschreibungstext (pdf)

Sorry - in German only:

Von Nachwuchswissenschaftlern für Nachwuchswissenschaftler

Wenn Sie Postdoc oder Doktorand sind, eine Idee für einen Workshop über eine aktuelle pflanzenwissenschaftliche Thematik mit interdisziplinären Ansätzen haben und eine Plattform für einen lebendigen Austausch von Doktoranden untereinander veranstalten möchten, schicken Sie Ihr Konzept bitte an den Vorstand der DBG, der Ihre Veranstaltung im Rahmen eines Eduard Strasburger-Workshops mit bis zu 5.000 € unterstützt. Bitte wenden Sie sich jederzeit an den Präsidenten der DBG. Der zweite Eduard Strasburger-Workshop fand im September 2016in München statt und hatte den Titel "Phylogenomics - The next generation of evolutionary botany". In ihrer Tagungsnachlese thematisieren die Organisatorinnen Susann Wicke und Dörte Harpke nicht nur die Tagungsschwerpunkte sondern auch die Sorgen der Nachwuchskräfte.

Details im aktuellen Ausschreibungstext (pdf)

The German Botanical Society has awarded the best Master theses of the previous year. Their abstracts are now on the website. Besides names of the awardees also titles and results are provided as texts and some of them also in images. The theses were carried out at seven universities.

DBG verleiht drei Wissenschaftspreise

Zur Eröffnung der Botanikertagung 2015 wurden die drei Preise der DBG zur Auszeichnung hervorragender Nachwuchswissenschaftler verliehen:

Eduard Strasburger-Preis 2015
an
Dr. Andreas Fleischmann
Evolution of genome size and chromosome number in the carnivorous plant genus Genlisea (Lentibulariaceae), with a new estimate of the minimum genome size in angiosperms. Ann Bot. 114(8): 1651-1663
mehr in der Pressemitteilung und in der Laudatio (pdf)

Wilhelm Pfeffer-Preis 2015
an
Dr. Manuel Steinbauer
The Effect of Spatial and Environmental Drivers on Patterns in Species Richness and Composition, Dissertation Uni Bayreuth
mehr in der Pressemitteilung und in der Laudatio (pdf)

Horst Wiehe-Preis 2015
an
Dr. Jonas Zimmermann
Design and valuation of DNA-Barcoding high throughput methods for analyzing diatom diversity: a test case along a south-north gradient in Central Europe (Rivers Lusatian Neisse/Oder), Dissertation Uni Giessen
mehr in der Pressemitteilung

Small Natural Products in Ecology and Evolution

From 21^st to 23^rd September 2014 (2 p.m. to 2 p.m.) the first Eduard Strasburger-Workshop of the German Botanical Society (DBG) will take place in Nuremberg, Germany. Entitled “Linking the biochemistry of small natural products to ecology and evolution” it is organized from young plant biologists for young plant biologists exclusively. The location where the participants will meet is the Hostel in Nuremberg located in the famous 500 year-old castle. Please send your application until 31st August to the organizers Dr. Nadine Meitinger and M.Sc. Daniel Geiger from the Department Biology at the Institute of Pharmaceutical Biology of the Friedrich-Alexander-University Erlangen-Nuremberg (FAU).
Application form (pdf)

Sorry, in German only

Drei Nachwuchsforschenden verlieh die DBG Preise für ihre hervorragenden Arbieten am Eröffnungstag der Botanikertagung 2013:

Eduard Strasburger-Preis 2013
an
Dr. Adrian Alder
The path from β-carotene to carlactone, a strigolactone-like plant hormone. Erschien in der Zeitschrift Science und ist Teil seiner Dissertation
mehr in der Pressemitteilung und in der Laudatio (pdf)

Wilhelm Pfeffer-Preis 2013
an
Dr. Dominik Großkinsky
Characterisation of Cytokinin mediated Resistance and Biocontrol Effects against Pseudomonas syringae in Arabidopsis and Tobacco. Dissertation an der Uni Graz
mehr in der Pressemitteilung und in der Laudatio (pdf)

Horst Wiehe-Preis 2013
an
Dr. Martin Bringmann
Identification of novel components that connect cellulose synthases to the cytoskeleton
mehr in der Pressemitteilung und in der Laudatio (pdf)

Students look for locations which offer internships and lecturers search for destinations for excursions: We therefore asked colleagues who are members of the DBG for ideas and experiences in our 2012 survey. All information is without guaranties. You are always welcome to complete or improve the listings that this nucleus of information pool will evolve. We hope that you will profit from the list.

please downlaod table "Excursions and Internships" (pdf)

Sorry, in German only

Auch dieses Jahr übernimmt die DBG wieder drei Patenschaften für Nachwuchsforscherinnen und -forscher im Rahmen des RISE-Programms (Research Intership in Science and Engineering) des DAAD. Das heißt sie ermöglicht drei jungen Wissenschaftlern einen Mitarbeiter für die eigene Dissertation für sich gewinnen zu können.
Wie das RISE-Programm funktioniert

Sorry, in German only

Auch dieses Jahr fördert die DBG ausländische Studierende, die einer hiesigen Doktorandin oder einem Doktoranden zur Hand gehen. Organisiert wird der Austausch, bei dem Nordamerikanische und Britische Studierende in deutsche Hochschulen und pflanzenwissenschaftliche Labore schnuppern, vom Deutschen Akademischen Austauschdienst (DAAD). In diesem „Research Internships in Science and Engineering (RISE)“ genannten Programm koordiniert der DAAD die Zusammenführung der Doktoranden-Praktikanten-Paare und erstellt das Ranking unter den eingegangenen Bewerbungen. Drei dieser Stipendien in diesem Jahr finanziert wieder die DBG.

Details zu RISE

Bericht über eine frühere Doktoranden-Praktikanten-Zusammenarbeit in den Pflanzenwissenschaften

Details beim DAAD

Applications for the organisation of the workshop can be submitted to the president all year round.

Application and Documentation

Application and documentation (German pdf file)

The DBG awards several prizes:

• The Wilhem Pfeffer Prize is being awarded biennially from funds of the Wilhelm-Pfeffer-Foundation for an outstanding PhD Thesis.
• The Prize for the Best Publiaction will be awarded yearly from funds of the Wilhelm Pfeffer Foundation.
• The Horst Wiehe Prize ("Förderpreis der Horst-Wiehe-Stiftung") is being awarded every second year for an outstanding scientific work in the field of Botany.
• On the occasion of the 100^th anniversary of the first edition of the "Lehrbuch für Botanik" by E. Strasburger, F. Noll, H. Schenk and A.F.W. Schimper, the "Strasburger Prize" was created in 1994. It is being awarded every second year for an outstanding and especially original botanical work of a scientist less than 35 years old, is endowed with 2.500 Euros and is supported by the publishing house Springer Spektrum.

Prize for the Best Plant Science Master Thesis is awarded every year at every participating university.

Young plant scientists are invited to organise a Eduard Strasburger Workshop to foster the interdisciplinary scientific exchange of expertise and networking. It will be organised by young scientists for young scientists under the auspices of a scientific institution, shall last for two about days and be addressed to 25-40 participants. Upon approval by the board the DBG offers up to 5,000 Euros for this.

Moreover DBG also offers Eduard Strasburger-Workshops focussing on Hot Topics.

On application the DBG gives travel grants to students and young scientists presenting an oral paper or a poster at the congress "Botanik-Tagung - International Conference of the German Society for Plant Sciences". The applicants must be members of the DBG. The deadlines concerning the travel grants are announced in DBG's newsletter and in the Intranet.

The society sponsorsthe attendance of young scientists at such meetings and conferences that focus on young scientists upon application.

For many years the society supported the RISE program (Research Internship in Science and Engineering) of the German Academic Exchange Service (DAAD): young scientists from abroad and Great Britain do research at a Germany university together with German Ph.D. candidates. And German students can apply for an internship in Northamerica.

At the moment the DBG is not involved in the RISE program.

The Wilhem Pfeffer Foundation of the DBG awards the Wilhem Pfeffer Prize every other year. The following scientists were endowed:

2024

Dr. Henryk Straube

Straube, Henryk (2023): Investigation of the metabolism of rare nucleotides in plants. Dissertation. Gottfried Wilhelm Leibniz Universität Hannover, 241 S., Referent: Prof. Dr. Claus-Peter Witte. DOI: https://doi.org/10.15488/13270 

read more in the press release and the laudatory speech (pdf)

2022

Dr. Rabea Meyberg

Rabea Meyberg (2020): Conserved key players required for Physcomitrella patens male fertility are affected by accumulation of (epi-) mutations. Dissertation https://archiv.ub.uni-marburg.de/diss/z2020/0063/   

read more in the German press release and in the Laudation (pdf)

2019

Dr. Jessica Lee Erickson    

Erickson JL (2019): Shaping plastid stromules. Dissertation, Faculty of Biology, Department of Plant Physiology, Martin Luther University Halle-Wittenberg. DOI: http://dx.doi.org/10.25673/13909

read more in our press release

Dr. Moisés Expósito Alonso

Expósito-Alonso M (2018): On climate change and genetic evolution in Arabidopsis thaliana. Dissertation. Max Planck Institute for Developmental Biology and Eberhard Karls University of Tübingen. DOI: http://dx.doi.org/10.15496/publikation-26332 

read more in our press release

2017

Dr. Inês Barbosa

Barbosa IC (2015): Trafficking and polarity control of the D6 PROTEIN KINASE from Arabidopsis thaliana. Doktorarbeit an der Technischen Universität München (TUM). Wesentliche Teile sind publiziert in:
Barbosa IC, Shikata H, Zourelidou M, Heilmann M, Heilmann I, Schwechheimer ( (2016): Phospholipid composition and a polybasic motif determine D6 PROTEIN KINASE polar association with the plasma membrane and tropic responses. Development 143(24):4687-4700. DOI: 10.1242/dev.137117
Barbosa IC, Zourelidou M, Willige BC, Weller B, Schwechheimer C (2014): "D6 PROTEIN KINASE activates auxin transport-dependent growth and PIN-FORMED phosphorylation at the plasma membrane. Developmental Cell 29(6):674-685. DOI: 10.1016/j.devcel.2014.05.006

read German press release

2015

Dr. Manuel Steinbauer

The Effect of Spatial and Environmental Drivers on Patterns in Species Richness and Composition

see German Press release

2013

Dr. Dominik Großkinsky

Characterisation of Cytokinin mediated Resistance and Biocontrol Effects against Pseudomonas syringae in Arabidopsis and Tobacco. Dissertation an der Uni Graz

see German Press release and Laudatio (pdf-Datei)

2011

Dr. Marco Todesco

Overt and Cryptic Natural Genetic Variation in Arabidopsis thaliana. Dissertation, MPI Tübingen. Some of the results are published in Nature.

see German Press release and Laudatio (pdf)

2009

Dr. Eva Nowack

Nowacks Doktorarbeit ist 2009 im Cuvillier Verlag Göttingen unter dem Titel „Paulinella chromatophora - a Model for the Acquisition of Photosynthesis by Eukaryotes“ erschienen (ISBN 978-3-86727-946-8).

see German Pressemitteilung and Laudatio (pdf file, 0,1 MB)

2006

Dr. Bationa Shahollari

Molecular analyses of the interaction between Arabidopsis thaliana and the endophytic fungus Piriformospora indica. Dissertation, Universität  

see Laudatio (pdf)

2004

Dr. Sophie Karrenberg van der Nat

Tree regeneration on the flood plain of an Alpine river. Dissertation, Universität

see Laudatio (pdf, 0,2 MB)

2002

Dr. Micheal Knoblauch

Entwicklung neuer Methoden zur Untersuchung der Struktur und Funktion des Transportphloems in vivo. Dissertation, Universität

see Laudatio (pdf, 0,2 MB)

2000

Dr. Christine Oesterhelt

A sweet live at pH 1 - Characterization of a sugar/polyol-uptake system in the unicellular acidophilic red alga Galdieria sulphurarua
Dissertation, Universität

1998

Dr. Christina Kühn

Charakterisierung und Lokalisierung des Saccharosetransporters SUT1 in Solanaceen. Dissertation, Universität

1996

Dr. Arthur Schüßler

Strukturelle und funktionelle Charakterisierung der Pilz/Blaualgen Endosymbiose Geosiphon pyriforme: Physiologie, Zellbiologie und Taxonomie. Dissertation, Universität

1993

Dr. Karin Hauser

Saccharomyces cerevisiae alpha-Agglutinin: Reinigung, Charakterisierung, Klonierung des Gens und Nachweis einer aktiven Domäne. Dissertation, Universität

1992

Dr. Rebecca Klink

Elektronenmikroskopische Darstellung der Tonoplasten-ATPase bei der C3-CAM-intermediären Pflanze Mesembryanthemum crystallinum. Dissertation, Universität

The Wilhem Pfeffer Foundation awards a Prize for the Best Plant Science Publication of a year which came out of a Master, Diploma or PhD thesis since 2006. The following scientists were endowed with the Best Paper Prize:

2025

Sara Leite Dias, Dr. Ling Chuang and Shenyu Liu

Leite Dias S, Chuang L, Liu S, Seligmann, B., Brendel, F. L., Gabriel Chavez, B., Hoffie, R. E., Hoffie, I., Kumlehn, J., Bültemeier, A., Wolf, J., Herde, M., Witte, C. P., D’Auria, J. C., Franke, J. (2024): Biosynthesis of the allelopathic alkaloid gramine in barley by a cryptic oxidative rearrangement. Science 383, 1448-1454. DOI: 10.1126/science.adk6112 

read more in Actualia

2023

Dr. Pratibha Kumari

Kumari, P., Dahiya, P., Livanos, P., Zergiebel, L., Kölling, M., Poeschl, Y., Stamm, G., Hermann, A., Abel S., Müller, S., Bürstenbinder, K. (2021): IQ67 DOMAIN proteins facilitate preprophase band formation and division-plane orientation. Nat. Plants 7, 739–747. https://doi.org/10.1038/s41477-021-00923-z

read more in Actualia

2021

Dr. Katharina Bursch

Bursch, K., Toledo-Ortiz, G., Pireyre, M., Lohr, M., Braatz, C., Johansson, H. (2020): Identification of BBX proteins as rate-limiting cofactors of HY5. Nature Plants, 6, 921–928. DOI: https://doi.org/10.1038/s41477-020-0725-0

read more in Actualia

2020

Dr. Norbert Bittner

Bittner, N., Hundacker, J., Achotegui-Castells, A., Anderbrant, O., Hilker, M. (2019): Defense of Scots pine against sawfly eggs (Diprion pini) is primed by exposure to sawfly sex pheromones. PNAS, 116, 24668-24675. DOI: https://doi.org/10.1073/pnas.1910991116

read more in Actualia

2019

Dr. Jutta Baldauf

Baldauf J.A., C. Marcon, A. Lithio, H. Schoof, D. Nettleton, F. Hochholdinger (2018): Single-Parent Expression is a general mechanism driving extensive complementation of non-syntenic genes in maize hybrids. Current Biology 28, 431–437. DOI: https://doi.org/10.1016/j.cub.2017.12.027

read more in Actualia

Dr. Aleksandra Sapala

Sapala A., A. Runions, A.-L. Routier-Kierzkowska, M. Das Gupta, L. Hong, H. Hofhuis, S. Verger, G. Mosca, C.-B. Li, A. Hay, O. Hamant, A.H.K. Roeder, M. Tsiantis, P. Prusinkiewicz, R. S. Smith (2018): Why plants make puzzle cells, and how their shape emerges. eLife. DOI: https://doi.org/10.7554/eLife.32794

read more in Actualia

2018

Dr. Katja Meyer

Meyer K., T. Köster, C. Nolte, C. Weinholdt, M. Lewinski, I. Grosse, D. Staiger (2017): Adaptation of iCLIP to plants determines the binding landscape of the clock-regulated RNA-binding protein AtGRP7. Genome Biology 18, 204. DOI: https://doi.org/10.1186/s13059-017-1332-x

read more in Actualia

Dr. Max Lauterbach

Lauterbach, M., Schmidt, H., Billakurthi, K., Hankeln, T., Westhoff, P. Gowik, U., Kadereit, G (2017): De novo Transcriptome Assembly and Comparison of C3, C3-C4, and C4 Species of Tribe Salsoleae (Chenopodiaceae). Front. Plant Sci. 8, 1939. DOI: https://doi.org/10.3389/fpls.2017.01939  

read more in Actualia

2016

Dr. Meret Huber

M. Huber, J. Epping, C. Schulze Gronover, J. Fricke, Z. Aziz, T. Brillatz, M. Swyers, T.G. Köllner, H. Vogel, A. Hammerbacher, D. Triebwasser-Freese, C. A. M. Robert, K. Verhoeven, V. Preite, J. Gershenzon, M. Erb (2016): A Latex Metabolite Benefits Plant Fitness under Root Herbivore Attack. Plos Biology. DOI: 10.1371/journal.pbio.1002332

Dr. Bettina Ohse

Ohse B, Hammerbacher A, Seele C, Meldau S, Reichelt M, Ortmann S, Wirth C (2016) Salivary cues: Simulated roe deer browsing induces systemic changes in phytohormones and defense chemistry in wild-grown maple and beech saplings. Functional Ecology. DOI: 10.1111/1365-2435.12717,

2014

Dr. Maria Will

Will M and Claßen-Bockhoff R (2014): Why Africa matters: evolution of OldWorld Salvia (Lamiaceae) in Africa. Annals of Botany 114: 61–83 DOI: 10.1093/aob/mcu081

Dr. David Heckmann

Heckmann D, Schulze S, Denton A, Gowik U, Westhoff P, Weber APM, Lercher MJ (2013): Predicting C4 Photosynthesis Evolution:
Modular, Individually Adaptive Steps on a Mount Fuji Fitness Landscape. Cell, 153, 1579–1588. DOI: 10.1016/j.cell.2013.04.058

2012

Dr. Katharine G. Rascher
&
Christine Hellmann

Katherine G. Rascher, Christine Hellmann, Cristina Máguas, Christiane Werner (2012): Community scale 15N isoscapes: tracing the spatial impact of an exotic N2-fixing invader. Ecology Letters 15: 484–491. DOI: 10.1111/j.1461-0248.2012.01761.x

2010

Dr. Michelle Ast
&
Dr. Ansgar Gruber

M. Ast, A. Gruber, S. Schmitz-Esser, H. E. Neuhaus, P. G. Kroth, M. Hoern & I. Haferkamp (2009): Diatom plastid depend on nucleotide import from the cytosol. PNAS 106, 3621-3626.

Dr. Katharina Bräutigam

K. Bräutigam, L. Dietzel, T. Kleine, E. Ströher, D. Wormuth, K.-J. Dietz, D. Radke, M. Wirtz, R. Hell, P. Dörmann, A. Nunes-Nesi, N. Schauer, A. R. Fernie, S. N. Oliver, P. Geigenberger, D. Leister, T. Pfannschmidt (2009): Dynamic plastid redox signals integrate gene expression and metabolism to induce distinct metabolic states in photosynthetic acclimation in Arabidopsis. Plant Cell 21, 2715-2732.

Dr. Jyothilakshmi Vadassery

Vadassery J, Ranf, S. Drzewiecki, C, Mithöfer A, Mazars, C, Scheel, D, Lee, J. Oelmüller R (2009): A cell wall extract from the endophytic fungus Piriformospora indica promotes growth of Arabidopsis seedlings and induces intracellular calcium elevation in roots. Plant Journal 59, 193-206.

2008

Dr. Susanne Horn

S. Horn, K. Ehlers, G. Fritzsch, M.C. Gil-Rodriguez, C. Wilhelm & R. Schnetter (2007): Synchroma grande spec. Nov (Synchromophyceae class. Nov. Heterokontophyta): An Amoeboid Marine Alga with Unique Plastid Complexes. Protist 158, 277-293, 2007

Dr. Holger Kreft

H. Kreft & W. Jetz (2007): Global Patterns and determinants of vascular plant diversity. PNAS, 104: 5925-5930.

2006

Dr. Uwe Simon

U.K. Simon, R. Bauer, D. Rioux, M. Simard, F. Oberwinkler (2004): The intercellular biotrophic leaf pathogen Cymadothea trofolii locally degrades pectins, but not cellulose or xyloglyucan in the cell walls of Trifolium repens. New Phytologist 165, 243-260.

Dr. Eva Nowack

E.C.M. Nowack, B. Podola, M. Melkonian (2005): The 96-well Twin-Layer System:  A novel Approach in the Cultivation of Algae. Protist 156, 239-251.

The Strasburger Prize is awarded every other year for an outstanding and unconventional work in the field of botany carried out by a young doctorate. It is donated by the Pubisher Springer Spektrum and is given by the German Botanical Society since 1994 according to the statutes.

Springer Spektrum publishing house donated the prize on the occasion of the 100^th anniversary of the first publishing of the book "Lehrbuch der Botanik" by Eduard Strasburger, Fritz Noll, Heinrich Schenck und A. F. Wilhelm Schimper.

The Prize comprises

• a document comprising the name of the award winner, the title of the award winning work and is underwritten by the president of the DBG
• a sum of Euros 2500,-
• a travel allowance for the award winner to join the "Botanikertagung" where the prize will be presented.

Proposing candidates

Proposals can be made by university lecturers who are members of the German Botanical Society only. The candidates should be younger than 36 years of age. No one can propose his/her own work. More Details are summarized in the statutes.

Deadlines and Calls

Calls are published on DBG's website.

The DBG awards the Eduard Strasburger Prize founded by Spektrum Akademischer Verlag (now: Springer-Spektrum) since 1994. Every other year an outstanding botanical research carried out by a young doctorate is choosen. The following scientists were endowed with the prize:

2024

Dr. Eliza Loo

Loo E.P.I., Durán P, Pang TP, Westhoff P, Deng C, Durán C, Lercher M., Garido-Oter, R. & Frommer W.B. (2024): Sugar transporters spatially organize microbiota colonization along the longitudinal root axis of Arabidopsis. Cell Host Microbe 32, 543-556.e6. DOI: https://doi.org/10.1016/j.chom.2024.02.014

read more in the press release

2022

Dr. Meike Hüdig

Meike Hüdig, Marcos A Tronconi, Juan P Zubimendi, Tammy L Sage, Gereon Poschmann, David Bickel, Holger Gohlke, Veronica G Maurino (2021): Respiratory and C4-photosynthetic NAD-malic enzyme coexist in bundle sheath cells mitochondria and evolved via association of differentially adapted subunits. The Plant Cell 34, 597-615. DOI: https://doi.org/10.1093/plcell/koab265

Marcos A. Tronconi, Meike Hüdig, M. Eric Schranz and Veronica G. Maurino (2020): Independent recruitment of duplicated β-subunit-coding NAD-ME genes aided the evolution of C4 photosynthesis in Cleomaceae. Front. Plant Sci. 11, 572080. DOI: https://doi.org/10.3389/fpls.2020.572080

read more in the German press release

2019

Dr. Constantin Mario Zohner

Zohner CM (2016): The biogeography, evolution, and function of leaf-out phenology studied with experimental, monitoring, and phylogenetic approaches. Dissertation, Fakultät für Biologie, Ludwig-Maximilians-Universität München. https://edoc.ub.uni-muenchen.de/21673/1/Zohner_Constantin.pdf  

read more in the press release

2017

Dr. Severin Irl

Irl SDH, Harter DEV, Steinbauer MJ, Puyol Gallego D, Fernández-Palacios JM, Jentsch A, Beierkuhnlein C (2015): Climate vs. topography – spatial patterns of plant species diversity and endemism on a high-elevation island. Journal of Ecology, 103, 1621–1633. DOI: 10.1111/1365-2745.12463

read more in the press release

2015

Dr. Andreas Fleischmann

Fleischmann AS, Todd PM, Rivadavia F, Sousa A, Wang W, Temsch EM, Greilhuber J, Müller KF, Heubl G (2014): Evolution of genome size and chromosome number in the carnivorous plant genus Genlisea (Lentibulariaceae), with a new estimate of the minimum genome size in angiosperms. Ann Bot. 114(8): 1651-1663. doi: http://dx.doi.org/10.1093/aob/mcu189
Rivadavia F, Gonella PM, Fleischmann AS (2013): A New and Tuberous Species of Genlisea (Lentibulariaceae) from the Campos Rupestres of Brazil. Systematic Botany 38(2): 464-470. doi: http://dx.doi.org/10.1600/036364413X666679
Fleischmann AS (2012): A Monograph of the Genus Genlisea. Redfern Natural History Productions Ltd. 728 pages, 614 images

read German press release and certificate (pdf)

2013

Dr. Adrian Alder

Alder A, Jamil M, Marzorati M, Bruno M, Vermathen M, Bigler P, Ghisla S, Bouwmeester H, Beyer P, Al-Babili S (2012): The path from β-carotene to carlactone, a strigolactone-like plant hormone. Science, DOI: 10.1126/science.1218094 als Teil der Dissertation.

read German press release and certificate (pdf)

2011

Dr. Hans-Henning Kunz

Biochemische Charakterisierung der Fettsäure-Beta-Oxidation als Teil des Dunkelstoffwechsels von Arabidopsis thaliana. Dissertation, Universität Köln: kups.ub.uni-koeln.de/3087/. Englische Originalpublikation bei The Plant Cell.

read German press release and Laudatio (pdf)

2009

Dr. Marion Eisenhut

Eisenhut M, Ruth W, Haimovich M, Bauwe H, Kaplan A, Hagemann M (2008): The photorespiratory glycolate metabolism is essential for cyanobacteria and might have been conveyed endosymbiontically to plants. PNAS. DOI: https://doi.org/10.1073/pnas.0807043105

read German press release and Laudatio (pdf)

2007

Dr. Ansgar Kahmen

Kahmen A, Perner J, Buchmann N (2005): Diversity dependent productivity in semi-natural grasslands following climate perturbations.
Functional Ecology, 19: 594-601

read Laudatio (pdf)

2004

PD Dr. Enrico Schleiff

Für seine Arbeiten über die Funktion, Struktur und Regulation der molekularen Maschine zur Erkennung und zum Transport kernkodierter Proteine über die äussere Hüllmembran von Plastiden höherer Pflanzen

read Laudatio (pdf file, 0.2 MB)

2002

Dr. Marc Götz

"Funktion und Regulation extrazellulärer Invertase in Höheren Pflanzen." Dissertation, Universität

2000

Dr. Sigrun Reumann

"Nachweis, Charakterisierung und Anreicherung eines Porins pflanzlicher Peroxisomen". Dissertation, Universität

1998

Dr. Jutta Papenbrock

"Magnesium Protoporphyrin IX-Chelatase: Ein Schlüsselenzym in der Tetrapyrrolbiosynthese". Dissertation, Universität

1996

Dr. Johannes Christian Vogel

"Multiple Origins of polyploids in European Asplenium (Pteridophyta)". Dissertation, Universität

1994

Dr. Karl-Ferdinand Lechtreck

"Untersuchungen über das Protein SF-Assemblin aus dem Bewegungsapparat der einzelligen Grünalge Spermatozopsis similis". Dissertation, Universität

The Horst Wiehe Prize (Förderpreis der Horst-Wiehe-Stiftung) is being awarded every other year for an outstanding scientific work in the field of Botany. It is awarded solely to young scientists upon receiving a doctorate or before becoming a lecturer.

The Prize comprises

• a document comprising the name of the award winner and the title of the award winning work. The document is underwritten by the president of the German Botanical Society.
• The award is endowed with € 1500,-. The endowment can increase over time.

The Prize can be allocated to two persons.

Founder

Horst Wiehe from Braunschweig, Germany, donated a sum of 50.000 DM (25,564.50 Euro) to the DBG from which the "Förderpreis der Horst-Wiehe-Stiftung" is being awarded. The board of the DBG accepted the Foundation in 1990 for which Horst Wiehe set the statutes.

The DBG awards the Horst Wiehe Prize for an outstanding PhD thesis every other year. The following early career scientists were endowed:

2024

Dr. Martin Lewinski

Lewinski M., Brüggemann M., Köster T., Reichel, M., Bergelt, T., Meyer, K., König, J., Zarnack, K., Staiger, D. (2024): Mapping protein-RNA binding in plants with individual-nucleotide-resolution UV cross-linking and immunoprecipitation (plant iCLIP2). Nature Protocols 19, 1183–1234. DOI: https://doi.org/10.1038/s41596-023-00935-3    

read more in the press release

2022

Kai Steffen Bartusch

Phanu T. Serivichyaswat, Kai Bartusch, Martina Leso, Constance Musseau, Akira Iwase, Yu Chen, Keiko Sugimoto, Marcel Quint, Charles W. Melnyk; High temperature perception in leaves promotes vascular regeneration and graft formation in distant tissues. Development 1 March 2022; 149 (5): dev200079. DOI: https://doi.org/10.1242/dev.200079

read more in the German press release

2019

Dr. Eva-Sophie Wallner

Wallner E-S (2018): Early events in phloem formation: Exploring the molecular network of SMXL3/4/5, Fakultät für Biowissenschaften. Heidelberg, Universität Heidelberg. Dissertation (Dr. rer. nat): 128. DOI: http://doi.org/10.11588/heidok.00025313

read more in the press release

2017

Dr. Birgit Oelschlägel

Oelschlägel B, v. Tschirnhaus M, Nuss M, Nikolić T, Wanke S, Dötterl S, Neinhuis C (2016): Spatio-temporal patterns in pollination of deceptive Aristolochia rotunda L. (Aristolochiaceae). Plant Biology 18: 928-937. http://onlinelibrary.wiley.com/doi/10.1111/plb.12503/full

Oelschlägel B, Nuss M, von Tschirnhaus M, Pätzold C, Neinhuis C, Dötterl S, Wanke S (2015): The betrayed thief - the extraordinary strategy of Aristolochia rotunda to deceive its pollinators. New Phytol 206, 342-351. DOI: 10.1111/nph.13210

read German press release

2015

Dr. Jonas Zimmermann

Design and valuation of DNA-Barcoding high throughput methods for analyzing diatom diversity: a test case along a south-north gradient in Central Europe (Rivers Lusatian Neisse/Oder)

read German press release

2013

Dr. Martin Bringmann

Identification of novel components that connect cellulose synthases to the cytoskeleton.

read German press release  and deed (pdf)

2011

Dr. Alexandra C. Furch

Calcium-regulierter Verschluss der Siebelemente. Dissertation, Justus-Liebig-Universität Gießen

read German press release and laudation (pdf)

2009

Mgr. Martin A. Lysak, Ph.D.

Mechanisms of chromosome number reduction in Arabidopsis thaliana and related Brassicaceae species (Proc. Natl. Acad. Sci. USA 103: 5224-5229)

read German press release and laudation (pdf)

2007

Dr. Iris Finkemeier

Antioxidant defence and redox regulation in plant mitochondria: The role of type II peroxiredoxin F. Dissertation, Universität

read laudation (pdf)

2005

Dr. Christian Jelich-Ottmann

Das Phytotoxin Fusicoccin: Strukturelle Grundlage seines Wirkmechanismus. Dissertation, Universität

read laudation (pdf)

2001

Dr. Peter Pimpl

Biochemische und zellbiologische Charakterisierung des COP Vesikel vermittelten Proteintransports in Pflanzen. Dissertation, Universität

read laudation (pdf)

Dr. Uwe Rascher

Der endogene CAM-Rhythmus von Kalanchoë daigremontiana als nichtlineares Modellsystem zum Verständnis der raum-zeitlichen Dynamik einer biologischen Uhr. Dissertation, Universität

read laudation (pdf file)

1999

Dr. Thomas Peterbauer

Structure, synthesis, and function of galactosylcyclitols in vigna seeds. Dissertation, Universität

1997

Dr. Mathias Herbst

Die Bedeutung der Vegatation für den Wasserhaushalt ausgewählter Ökosysteme. Dissertation, Universität

1995

Dr. Frank Hübel

Phytasen und Phytat in Wurzeln von Mais. Dissertation, Universität

1993

Dr. Gerhard Zotz

Photosynthese und Wasserhaushalt von Pflanzen verschiedener Lebensformen im Kronenbereich des tropishen Regenwaldes auf der Insel Barro Colorado Island, Panama. Dissertation, Universität

Every year the DBG awards a prize for the best master thesis in plant science at every participating university. The award comprises a certificate and a 100 Euros prize.

Mode of Application and Awarding Procedure

To apply every young plant science person shall hand his/her master thesis over to the representative the DBG has at every university all year round. Together with other plant science university lecturers who are interested the contact person decides in October which of the master theses is the best. The contact person also decides about the awarding procedure, which can be the annual faculty ceremony, a graduation ceremony, or a personal presentation. The award winning thesis will be listed together with the scientist’s name, the title and a short summary on the website of the DBG.

Publication of the Thesis Summary

The summary of the award winning thesis to be published on the DBG website shall contain the name of the prize winner, the title of the thesis, one introductory sentence, one or two sentences about the methods used, and a few easily comprehensible sentences about the results as well as a conclusion or an outlook. We also provide a possibility to enrich the text with one or two photos / graphics to serve as “appetizer” or summarizing image. Please also quote a link where the thesis can be found in the internet to allow further reading. Please send the text as a word file and the images as originals (not included into the word document) within four weeks to the following e-mail: masterarbeit [at] deutsche-botanische-gesellschaft.de

Since 2014 the German Society for Plant Sciences (DBG) awards a prize for the best plant science master thesis, which was carried out at each of the participating universities. The following young scientists received the honor:

Sorry in German only:

Christodoulos Filippis erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Johann Wolfgang Goethe-Universität Frankfurt im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Untersuchungen zur Rolle von PaRCF1 und PaRCF2 bei der Organisation von Atmungskettensuperkomplexen bei Podospora anserina’ "

Wie er herausfand, ist das Protein PaRCF1 essentiell für die Bildung Komplex-IV-enthaltender Superkomplexe in dem Pilz Podospora anserina

Sorry in German only:

Sophie Steinhagen erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Justus-Liebig-Universität Gießen im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Ultrastructure of cells of Cryptochlora perforans (Chlorarachniophyta)"

Ihr gelang der erste Nachweis des zusätzlichen Zellkerns in der grünen Amöbe Cryptochlora perforans

Sorry in German only:

Christian Köttig erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Technischen Universität München im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Redoxregulation von Proteinphosphatasen des Typs 2C"

Er untersuchte die Redoxregulation der Proteinphosphatasen ABI1, ABI2, HAB1 und PP2CA durch Wasserstoffperoxid

Sorry in German only:

Maximilian Lauterbach erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Johannes Gutenberg-Universität Mainz im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Wüsten-Pflanzen der Gruppe Zygophyllum s.l. zeigen enorme Vielfalt und evolutionäre Flexibilität in ihrer Blattanatomie"

Sorry in German only:

Florian Ulm erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Universität Kaiserslautern im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Below ground processes of a native and an invasive legume as a driver for nitrogen distribution on community scale"

Weil er beschrieb, wie Veränderungen in der Rhizosphäre den Erfolg einer pflanzlichen Invasion beeinflussen

Sorry in German only:

Sebastian Wittek erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Universität zu Köln im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Prosoaulax – A Dinoflagellate with Mysterious Plastids"

Er zeigte, dass manche mixotrophe Prosoaulax-Dinoflagellaten ihre Plastiden nutzen um Nahrungsmangel zu überbrücken.

Sorry in German only:

Klaus Herburger erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Leopold-Franzens-Universität Innsbruck im Jahr 20xx erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Zellwandkomponenten und ökophysiologische Charakterisierung der streptophytischen Grünalgen Klebsormidium sp. und Zygnema sp."

Der Preisträger stellte die zellulären und physiologischen Anpassungen von Grünalgen an das Landleben dar

Sorry in German only:

Philip Albers erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Freien Universiät Berlin im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"In vivo regulation of Arabidopsis thaliana CPK5 in plant pathogen defense"

Regulationsmechanismen des zentralen Enzyms CPK5 in der pflanzlichen Bakterienabwehr

Sorry in German only:

Simon Fraas erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Universität Hamburg im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Hansa-Trace - Ein System zur automatischen Hochdurchsatz-Erfassung der schnellen Wachstumseffekte bei Arabidopsis thaliana L. HEYNH"

Die Software Hansa-Trace misst schnelles Wurzelwachstum und unterstützt Hochdurchsatz-Phänotypisierung

Sorry, in German only:

Marcel Kansy erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Universität Leipzig im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Einfluss von Lipiden auf die Struktur und Funktion von Photosystem II"

Wie er herausfand, unterstützen Lipide der Chloroplastenmembran die Struktur und Funktion des Photosystems II oder leiten dessen Auflösung ein

Sorry, in German only:

Frederic D. Schramm erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Philipps-Universität Marburg im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Analysis of the peroxisomal membrane proteome of the diatom Phaeodactylum tricornutum and in vivo localization studies of putative peroxisomal proteins"

Damit gewährte er einen Einblick in das Proteom der Peroxisomen der Kieselalge Phaeodactylum tricornutum

Sorry, in German only:

Verena Lauströer erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der Universität Bielefeld im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Influence of mycotrophic degree on growth response for two plant species in single and competition treatments under conditions promoting parasitism by arbuscular mycorrhizal fungi"

New understanding of species-specific reactions dependent on mycotrophy level on AMF induced parasitism-promoting conditions

Sorry, in German only:

Friedrich Kirsch erhielt den Preis für die beste botanische Master-Arbeit, die an der Universität Rostock im Jahr 2014 erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Titel der ausgezeichneten Arbeit

"Integration des cyanobakteriellen Glyceratwegs aus Synechocystis sp. PCC6803 in die Photorespiration von Arabidopsis thaliana"

Er fand einen cyanobakteriellen "Bypass" der pflanzlichen Photorespiration

For ten years the society sponsored undergraduate students to conduct research at a German institute or university. With this the DBG continued to promote the RISE Program (Research Internship in Science and Engineering) of the DAAD organization (Deutsch Akademischer Austauschdienst) in the years from 2005 to 2015: Undergraduates from the USA, Canada or Great Britain visit German universities or scientific institutes and do research together with German graduates. Since 2009 the DAAD also sponsors the visit of young German researchers in Northern America. Both parties profit from this colaboration. Or how a participant puts it: "The internship furthered my career in three major ways."

More about the DAAD program

How a US-student described her stay at a German institute which investigates algae "It was an experience of a lifetime"

Sorry, in German only

Endlich eine helfende Hand bei der eigenen Doktorarbeit. Was wie ein Traum klingt, ermöglicht der DAAD: Die DBG sponserte viele Jahre lang jeweils drei RISE-Stipendien für ausländische Studierende, die deutsche Graduierte bei der Forschung unterstützten. Was das für die Beteiligten bringt, beschreibt die Redakteurin der Gesellschaft. Zusätzlich verrät sie Tipps und Tricks, wie man einen Praktikanten für sich gewinnt, denn um diese muss man ein wenig werben.

To support young researchers is an important objective of our society. To do so the Society has developed several instruments, such as prizes, travel allowances, sponsoring of meetings and participation of young scientists at conferences.

Christoph Hahn's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Oldenburg University in the year 2015.

Title of awarded thesis

"The diversity of kale: Glucosinolate content and phylogenetic relationships"

The content of five glucosinolates in 25 different kale varieties are compared with the phylogenetic relationships of the varieties. The study demonstrates the diversity of kale and the importance of preserving a broad genepool for future breeding purposes.

Eva Laura von der Heyde's work was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2015.

Title of the awarded thesis

"Study of taxonomically restricted gene families in Volvox carteri"

She identified and analysed those gene families in the multicellular green algae Volvox carteri that developed during evolution from unicellular to multicellular organisms. These gene families could be crucial for evolution of multicellularity.

Christoph Tim Krannich's work was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rostock University in the year 2015.

Title of the awarded thesis

"Role of the ethylene-signaling-pathway with regard to drought tolerance and storage of potatoes"

A set of molecular SSR-markers for practical breeding has been developed and tested in two different bulks, with one marker showing significant association to drought tolerance.

Franziska Walther's work was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Goethe University Frankfurt in the year 2015.

Title of the awarded thesis

"Flora and vegetation of pavement grooves in the city of Frankfurt am Main"

She found almost one quarter of all taxa registered in Frankfurt to occur in pavement grooves, which occupy only 1 % of the area of Frankfurt. Remarkably, a spontaneous appearance of Mazus pumilus was documented for the first time in Germany.

Stefanie Janine Jung's work was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Giessen University in the year 2015.

Title of the awarded thesis

"Salt tolerance and genetic variability of Prunus serotina Ehrh."

She found out that the invasive black cherry reacts differently to saline aerosols depending on their stages of development. However, a locational advantage due to an increased salt tolerance can be excluded.

Johanna Kozak's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out atTechnische Universität München in the year 2015. 

Title of thesis

"Dwarf, subalpine coniferous forests on permafrost lenses below the treeline in the Swiss Alps"

The first phytosociological description of dwarf plants on proven permafrost lenses suggest that there may be two differnt plant communities which are now further investigated.

Barbara Jakobs's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Konstanz University in the year 2015

Title of awarded thesis

"Characterization of the physiological function of the mitochondrial protease DEG10 in Arabidopsis thaliana"

By combining physiological and genetic analyses she found first evidence that the protein DEG10 plays an important role in root growth in Arabidopsis especially under temperature stress

In the year 2014 DBG's representatives at 13 universities evaluated the master theses in plant sciences. The following persons received the award (in alphabetical order):

Philip Albers (FU Berlin):
In vivo regulation of Arabidopsis thaliana CPK5 in plant pathogen defense
more in the German summary

Christodoulos Filippis (Goethe-Universität Frankfurt): 
Untersuchungen zur Rolle von PaRCF1 und PaRCF2 bei der Organisation von Atmungskettensuperkomplexen bei Podospora anserina’
more in the German summary

Simon Fraas (Universität Hamburg):
Hansa-Trace - Ein System zur automatischen Hochdurchsatz-Erfassung der schnellen Wachstumseffekte bei Arabidopsis thaliana L HEYNH more in the German summary with images

Klaus Herburger (Universität Innsbruck):
Zellwandkomponenten und ökophysiologische Charakterisierung der streptophytischen Grünalgen Klebsormidium sp. und Zygnema sp.
more in the German summary with images

Marcel Kansy (Universität Leipzig):
Einfluss von Lipiden auf die Struktur und Funktion von Photosystem II
more in the German summary

Friedrich Kirsch (Universität Rostock):
Integration des cyanobakteriellen Glyceratwegs aus Synechocystis sp. PCC6803 in die Photorespiration von Arabidopsis thaliana
more in the German summary

Christian Köttig (TU München):
Redoxregulation von Proteinposphatasen des Typs C2
more in the German summary with images

Verena Lauströer (Universität Bielefeld):
Influence of mycotrophic degree on growth response for two plant species in single and competition treatments under conditions promoting parasitism by arbuscular mycorrhizal fungi
more in the summary with images

Maximilian Lauterbach (Johannes Gutenberg-Universität Mainz):
Phylogeny and biogeography of Zygophyllum s.l. (Zygophyllaceae)
more in the German summary with images

Frederic Schramm (Philipps-Universität Marburg):
Analysis of the peroxisomal membrane proteome of the diatom Phaeodactylum tricornutum and in vivo localization studies of putative peroxisomal proteins
more in the German summary mit Bildern

Sophie Steinhagen (Justus-Liebig-Universität Giessen):
Ultrastruktur der Zellen von Cryptochlora perforans (Chlorarachniophyta)
more in the German summary with images

Florian Ulm (TU Kaiserslautern):
Below ground processes of a native and an invasive legume as a driver for nitrogen distribution on community scale
more in the German summary with images

Sebastian Wittek (Universität zu Köln):
Prosoaulax, a dinoflagellate with mysterious plastids
more in the German summary with images

In the year 2015 DBG's representatives at the participating universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Christoph Hahn (Carl-von-Ossietzky Universität Oldenburg):
The diversity of kale: Glucosinolate content and phylogenetic relationships
more in the summary with images

Barbara Jakobs (Universität Konstanz):
Charakterisierung der physiologischen Funktion der mitochondrialen Protease DEG10 in Arabidopsis thaliana
more in the summary

Stefanie Jung (Justus-Liebig-Universität Gießen):
Salt tolerance and genetic variability of Prunus serotina Ehrh.
more in the summary with images

Johanna Kozak (Technische Universität München):
Dwarf, subalpine coniferous forests on permafrost lenses below the treeline in the Swiss Alps
more in the summary with images

Christoph Tim Krannich (Universität Rostock):
Role of the ethylene-signaling-pathway with regard to drought tolerance and storage of potatoes
more in the summary

Franziska Walther (Goethe-Universität Frankfurt):
Flora and vegetation of pavement grooves in the city of Frankfurt am Main
more in the summary with images

Eva Laura von der Heyde (Universität Bielefeld):
Study of taxonomically restricted gene families in Volvox carteri 
more in the summary with images

Paulina Anna Zigelski's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Hamburg University in the year 2016.

Title of awarded thesis

"Molecular biogeography of the Syzygium guineense complex: How environment and genetics push suffrutication in Africas Miombo region"

For the first time the origins of „underground trees“ in southern Africa were investigated in detail using a model species: an interaction of environmental and genetic factors play a crucial role in their evolution.

Dominika Kundel's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Konstanz University in the year 2016.

Title of the awarded thesis

"Bio-Effector Application: Impact on Growth Performance of maize and effect on associated arbuscular mycorrhizal fungi."

Plant extraction products and tiny soil organisms, so called Bio-Effectors might improve current fertilization strategies. The methods applied in this thesis might be helpful in further investigations on this subject.

In the year 2016 DBG's representatives at 5 universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Herbert Braunschmid (Universität Salzburg)
Divergent floral traits and pollinators of Cypripedium calceolus L.
more in the summary with image

Ina Burghardt (Goethe Universität Frankfurt)
"The impact of plastid immunophilins on light acclimation of Arabidopsis thaliana.
more in the summary with image

Dominika Kundel (Universität Konstanz)
Bio-Effector Application: Impact on Growth Performance of maize and effect on associated arbuscular mycorrhizal fungi.
more in the summary with image

Laura Mosebach (Universität Münster)
Regulation of photosynthetic electron transfer via PGRL1 and PGR5 in Chlamydomonas reinhardtii.
more in the summary with images

Wilena Telman (Universität Bielefeld)
Zur Funktion des 2-Cystein Peroxiredoxins und des Cyclophilin 20-3 innerhalb des Redox-regulatorischen Netzwerks von A. thaliana.
more in the summary

Paulina Anna Zigelski (Universität Hamburg)
“Molecular biogeography of the Syzygium guineense complex: How environment and genetics push suffrutication in Africas Miombo region“
more in the summary with images

Laura Mosebach's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at xxUniversity in the year 2016.

Title of awarded thesis

"Regulation of photosynthetic electron transfer via PGRL1 and PGR5 in Chlamydomonas reinhardtii"

The proteins PGRL1 and PGR5 are potentially involved in the recruitment of Ferredoxin:NADP+ Reductase (FNR) to the thylakoid membrane which is involved in the photosynthetic electron transport in the green alga.

Ina Burghardt 's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Goethe University Frankfrut in the year 2016.

Title of awarded thesis

"The impact of plastid immunophilins on light acclimation of Arabidopsis thaliana."

Plastid FKBP-type immunophilins are putative regulators of photosynthetic complexes. Knocking out one of these FKBPs led to loss of antenna movement (state transitions), the required STN7-kinase is active.

Wilena Telman's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielfeld University in the year 2016.

Title of awarded thesis

"Function of the 2-cystein peroxiredoxin and cyclophilin 20-3 within the redox-regulatory network in A. thaliana"

The obtained results gave evidence that the chloroplastidic 2-CysPrx-Cyp20-3 module links the redox, protein and thiol homeostasis in the context of cellular stress adaptation.

Herbert Braunschmid's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Salzburg University in the year 2016.

Title of the awarded thesis

"Divergent floral traits and pollinators of Cypripedium calceolus L."

The work analyses whether divergent floral traits of the lady's-slipper orchid (Cypripedium calceolus) along an altitudinal gradient are driven by pollinator mediated selection.

In the year 2017 DBG's representatives at several universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Anže Žerdoner Čalasan (Ludwig-Maximilians-Universität München)
Morphological, phylogenetic and taxonomic analysis of selected Trachelomonas (Euglenida) strains
more in the summary with image

Jan Hendrik Hoerner (Universität Bielefeld)
Allelopathic effects of the invasive plant Erodium cicutarium on agricultural crop plants
more in the summary with two images

Hannah Elisa Krawczyk (Universität Münster)
Influence of complex-type N-glycosylation on brassinosteroid signaling in Arabidopsis thaliana
more in the summary with image

Birte Peters (Universität Salzburg)
Epiphytic bacteria on lettuce affect the feeding behavior of an invasive pest slug
more in the summary with two images

Anike Schaller (Universität Kiel)
Untersuchungen zur Rolle von WHIRLY-Proteinen in der Kommunikation zwischen Zellkern und Organellen
more in the summary with image

Linda Titkemeier (Carl von Ossietzky-University Oldenburg)
Entwicklung geeigneter Lernhilfen für die Pflanzenbestimmungsübungen
more in the summary

Anže Žerdoner Čalasan's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ludwig-Maximilians-Universität München (LMU) in the year 2017

Title of awarded thesis

"Morphological, phylogenetic and taxonomic analysis of selected Trachelomonas (Euglenida) strains"

Anže Žerdoner Čalasan clarified three taxa of Trachelomonas taxa that were validly described already 100 years ago. In doing this he was able to apply also genetic information for reliable species determination.

Jan Hendrik Hoerner's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2017.

Title of awarded thesis

"Allelopathic effects of the invasive plant Erodium cicutarium on agricultural crop plants"

The invasive common stork´s-bill Erodium cicutarium causes yield reduction of various crops in North America. Jan Hendrik Hoerner examined responsible allelochemicals, natural substances produced by the stork´s-bill, which are able to suppress the growth of other plants. He fractionated phenolic compounds with high inhibitory effects, even in minor concentrations.

Hannah Elisa Krawczyk's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at xxUniversity in the year 2017

Title of awarded thesis

"Influence of complex-type N-glycosylation on brassinosteroid signaling in Arabidopsis thaliana"

Hannah Elisa Krawczyk attempts to elucidate specific functions of N-glycosylated proteins in plants. She now found a correlation between the inability to form complex-type or hybrid-type N-glycans in the Golgi apparatus and an altered sensitivity towards the two phytohormones brassinolide (BL) and abscisic acid (ABA).

Birte Peters's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Salzburg University in the year 2017.

Title of awarded thesis

"Epiphytic bacteria on lettuce affect the feeding behavior of an invasive pest slug"

This study showed for the first time that lettuce leave surface associated bacteria can directly affect the feeding behavior of a generalist herbivore.

Anike Schaller erhielt den Preis für die beste pflanzenwissenschaftliche Master-Arbeit, die an der xxUniversitätxx im Jahr 20xx erstellt wurde, von der Deutschen Botanischen Gesellschaft.

Anike Schaller's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at  Kiel University in the year 2017

Title of awarded thesis

"Investigations into the role of WHIRLY proteins in communication between nucleus and organelles"

Schaller has shown, that the inhibition of the chloroplast's development coincides with increased expression of nuclear genes encoding anti-stress proteins such as WHIRLY2 in mitochondria.

In the year 2018 DBG's representatives at several universities evaluated master theses in the plant sciences. The following persons received the award (in alphabetical order):

Benjamin Al (TU München)
Elucidation of the biological significance of post-translational modifications of Arabidopsis TRAPPII tethering complex proteins
more in the summary

Mareike Busche (Universität Bielefeld)
Functional characterisation of two flavonol synthases and an anthocyanidin synthase from Musa acuminata
more in the summary with image

Michael Gasper (Universität Münster)
Impact of lysine deacetylation on Arabidopsis thaliana seed germination physiology
more in the summary with image

Marc Halder (Universität Konstanz)
Investigating the competitive advantage of functional NPQ in Phaeodactylum tricornutum
more in the summary

Stefan Lucius (Universität Rostock):
Charakterisierung des Phänotyps von Arabidopsis-antisense-PGPase-Pflanzen nach Expression cyanobakterieller PGPasen
more in the summary

Fabian-Philipp Sylvester (FU Berlin)
Targeted „genome editing“ via CRISPR/Cas9 and characterization of CDPKs in stress response
more in the summary

Fabian-Philipp Sylvester's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at FU Berlin in the year 2018.

Title of awarded thesis

"Targeted „genome editing“ via CRISPR/Cas9 and characterization of CDPKs in stress response"

This work shows the great potential of CRISPR/Cas9 regarding the analysis of coupled inherited isoforms of a gen family, here a CDPK gene cluster. Sylvester for the first time generated a triple mutant including cpk21, cpk23 using CRISPR/Cas9.

Stefan Lucius's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rostock University in the year 2018.

Title of awarded thesis

"Phenotypical characterization of Arabidopsis antisense PGPase plants expressing putative cyanobacterial PGPases"

In this study we analyzed to what extent the expression of four putative 2-phosphoglycolate phosphatases (PGPases) from the cyanobacterium Synechocystis sp. PCC 6803 can complement the photorespiratory phenotype of Arabidopsis thaliana antisense PGPase plants.

Marc Halder's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at University of Constance in the year 2018.

Title of awarded thesis

"Investigating the competitive advantage of functional NPQ in Phaeodactylum tricornutum"

By means of competition experiments the effect of NPQ on the growth performance of a diatom under natural simulated light conditions were analyzed.

Michael Gasper's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Münster University in the year 2018.

Title of awarded thesis

"Impact of lysine deacetylation on Arabidopsis thaliana seed germination physiology"

This work shows that chemical inhibition of lysine deacetylase activity during seed germination decreased germination speed. Genetic experiments indicated that lysine deacetylases can regulate hormonal signalling during seed germination.

Benjamin Al's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at TU München in the year 2018.

Title of awarded thesis

"Elucidation of the biological significance of post-translational modifications of Arabidopsis TRAPPII tethering complex proteins"

Al charakterisierte das Modul TRAPPII, das eine entscheidende Komponente für die Stressphysiologie und Anpassungsfähigkeit von Pflanzen ist.

Mareike Busche's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2018.

Title of awarded thesis

"Functional characterisation of two flavonol synthases and an anthocyanidin synthase from Musa acuminata"

This work contributes to understanding of flavonol and anthocyanidin synthesis in Musa acuminata (banana) and provides a basis for further research towards increased flavonoid production through the analysis of two involved enzymes.

In the year 2019 DBG's representatives at the following universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Helen Ballasus (Leipzig University)
Species effects on temperature regulation mechanisms in the tree canopies at the Leipzig canopy crane
more in the summary with images

Mary Beyer (Paris-Lodron-Universität Salzburg)
Is heavy metal hyperaccumulation in Noccaea caerulescens acting as a defence mechanism against herbivores?
more in the summary

Paul David Grünhofer (Universität Bonn)
Formation and chemical composition of suberin in poplar roots
more in the summary

Natalie Hering (Karlsruher Institut für Technologie, KIT)
In-situ hybridization in Salvia flowers and closely related Lamiaceae for the detection of developmental genes
more in the summary

Jannes Höpke (Carl von Ossietzky-Universität Oldenburg)
The intricate species boundary between Veronica spicata and V. orchidea (Plantaginaceae)
more in the summary with image

Melanie Kastl (Universität zu Köln)
Functional characterization of the Ustilago maydis organ-specific effectors: UMAG05306 and UMAG11060
more in the summary

Cathrin Manz Philipps-Universität Marburg)
Diversity assessment of the ectomycorrhizal genus Russula in tropical montane forests in Panama
more in the summary with image

Erik Pischke (Rostock University in cooperation with Bayreuth University)
The role of the leucine biosynthesis for Pb tolerance in Arabidopsis thaliana
more in the summary

Felix Rehms (Westfälische Wilhelms-Universität Münster)
Development and application of genetically encoded fluorescent sensors for hypoxia investigation in plants
more in the summary

Nicola Schmidt (Technische Universität Dresden)
Characterisation of the endogenous phytopararetrovirus beetEPRV3 in the sugar beet genome (Beta vulgaris), a new member of the florendoviruses within the Caulimoviridae family
more in the summary with image

Philipp Zamzow (Universität Bielefeld)
Development and evaluation of selected orchards in the city of Bergkamen between 1990 and 2018
more in the summary with images 

Felix Rehms's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Westfälische Wilhelms-Universität Münster in the year 2019.

Title:

Development and application of genetically encoded fluorescent sensors for hypoxia investigation in plants

Rehms documents the visualization of Ca²⁺-accumulation in energy-deprived cells and the subsequent calcium signal propagation in Arabidopsis thaliana seedlings during prolonged oxygen restriction. He also started the development of genetically coded fluorescent oxygen sensors for use in-planta.

With regards to the growing frequency of extreme precipitation and flooding events caused by global climate changes, tolerance to oxygen deprivation (hypoxia; assumedly the most severe plant stress caused by prolonged submergence) is rapidly gaining relevance as a trait in crop breeding, even though, as of yet, the underlying mechanisms are mostly unknown.

To shed light on the role of second messengers in a plant’s perception and signal transduction of hypoxic conditions or the resulting energy crisis (caused by inhibition of aerobic respiration), genetically encoded fluorescent sensors of cytosolic Ca²⁺ and ATP concentration were employed for microscopic investigation of submerged Arabidopsis thaliana seedlings in a spatio-temporal resolution.

This way, he was able to record multiple waves of Ca²⁺-elevations, which were assumedly triggered by the collapse of energy upkeep and subsequent breakdown of active transport mechanisms that ensured the upkeep of steep ion gradients across membranes. Starting from the first energy depleted tissues or cells this wave spreads outwards and across the full seedling. The dynamics of these waves and comparisons to ATP monitoring in hypoxic seedlings suggests active signal propagation, rather than a universal increase caused exclusively by energy deprivation and passive ion leakage.

Additionally, this work documented the beginning development of genetically coded fluorescent oxygen indicators. Such oxygen sensors can be ubiquitously expressed in all tissues and can be applied in-vivo to monitor ongoing developments. In contrast to chemical and physical oxygen measurements, this does not cause any additional plant stress. This makes the fluorescent sensors ideal for the investigation of the oxygen dependency of signals in hypoxic plants. On top of that, the sensors’ independence of plant adaption or developmental mechanisms may lead to the identification of hypoxic niches that were not implicated by expression of hypoxia marker genes.

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Felix Rehms conducted this work at the institute of Plant Biology and Biotechnology (IBBP) in the group of Prof. Dr. Jörg Kudla.

Jannes Höpke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Carl von Ossietzky-Universität Oldenburg in the year 2019.

Title:

The intricate species boundary between Veronica spicata and V. orchidea (Plantaginaceae)

For the fist time a systematical comparison regarding missing data in combination with missing allele-dosis-information for population genetical methods like PCA/PCoA and STRUCTURE was conducted. Moreover, genetical material from the type localities of V. barrelieri subsp. crassifolia und V. tzesnae was analysed for the first time in this study.

The aim was to analyse the potentially hybridising species Veronica spicata and V. orchidea (Plantaginaceae) regarding their species boundary. Therefore, both species and morphologically similar species were analysed using Genotyping-by-Sequencing (GBS). The same question was already analysed by Bardy et al. (2011) using AFLP data but we were not able to completely confirm their results. To get a better understanding of how mixed ploidy-levels, the influence of missing data, and missing allele-dosis-information influence population genetical analyses, simulations and analyses of GBS data were conducted to reveal the reasons for the observed differences. Hereby a bug in the programme ipyrad was found out, the importance of paralogs was analysed and the difference between the coding of AFLP and diploidised SNP-Data was worked out

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Jannes Höpke conducted this work in the Institute for Biology and Environmental Sciences in the working group Biodiversity and Evolution of Plants of Prof. Dr. Dirk Albach

see another image

Mary Beyer's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Salzburg University in the year 2019.

Title

Is heavy metal hyperaccumulation in Noccaea caerulescens acting as a defence mechanism against herbivores?

Mary Beyer found out that accumulated heavy metals can have a deterring effect on herbivores, supporting the “elemental defence hypothesis”. However, the degree of this effect depends largely on the type of heavy metal and the species of herbivore as the feeding experiments showed.

The aim of this thesis was to provide new insights to the “elemental defence hypothesis”. According to this hypothesis, heavy metals act as a defence mechanism, by deterring or killing herbivores and pathogens, which led to a higher accumulation in certain plants (hyperaccumulators). Four types of herbivores (Arion vulgaris, Vanessa cardui, Plutella xylostella and Pieris rapae) were offered plants of the hyperaccumulator Noccaea caerulescens, treated with different concentrations of nickel and zinc, in a free choice feeding trial. The feeding damage on each plant was determined and thus it was assessed if nickel and/or zinc had any effect on the herbivores feeding behaviour.

The results support a significant correlation of feeding preferences and foliar zinc concentrations, reducing herbivory by up to 20%. However, this was not the case for foliar nickel concentrations, though a tendency of some herbivores preferring low levels of nickel could be observed. This shows that the effect of accumulated heavy metals on herbivory depends largely on the type of metal and species of herbivore.

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Mary Beyer conducted this work at the institute for ecology and evolution at Salzburg University in the working group of Prof. Hans-Peter Comes.

Nathalie Hering's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at KIT Karlsruhe in the year 2019.

Title:

In-situ hybridization in Salvia flowers and closely related Lamiaceae for the detection of developmental genes

She detected an unexpected occurrence of B-class identity genes in the ovary of adult Salvia flowers and closely related Lamiaceae

The flower is an evolutionary key innovation that makes a major contribution to the conservation of the species, as a specialized flower-pollinator interaction is the key to preserve the genetic lineage for many species. Within the flower development, there exists so-called "Genes of Speciation", which are significantly involved in producing reproductive barriers. From this, the debate about the species concept could be resolved, as an analysis of these genes could allow a systematically correct classification of the species. In order to understand the flower development in Salvia and closely related Lamiaceae, the temporal and spatial expression pattern of participating homeotic genes must be considered comparatively. Within this work, the expression of the B-class developmental genes GLOBOSA (GLO) and DEFICIENS (DEF) was investigated qualitatively and quantitatively as well as with the help of in-situ hybridization (ISH) in adult Salvia flowers as well as closely related Lamiaceae. ISH is a molecular biology method for the specific detection of nucleic acids in the cell of histological sections in vivo. By applying this method, the developmental genes GLO and DEF could be successfully localized via ISH in the ovary and stamen of flowers of the Lamiaceae.

The occurrence of the B-class identity gene GLO in the stamens corresponds to the ABC model according to Coen and Meyerowitz. The unexpected localization of the two developmental genes GLO and DEF in the ovary might indicate an evolutionary young, unknown protein or point to a repression of the developmental genes by an unknown microRNA in the fourth whorl. The occurrence of the developmental genes in flowers is confirmed by a qualitative and quantitative gene expression analysis. Accurate temporal expression patterns of the developmental genes could not be detected, only that these genes occur more frequently in late developmental stages of flowering. However, the presence of DEF in the leaf implies an early involvement in the combinatorial network of flower development, in addition to its proper function as a B-class identity gene.

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Nathalie Hering completed the work at the Botanical Institute I, Department of Biodiversitiy of the Karlsruhe Institute of Technology in the working group of Prof. Dr. Peter Nick.

Philipp Zamzow's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2019.

Title of the thesis: Development and evaluation of selected orchards in the city of Bergkamen between 1990 and 2018

Two aspects were examined in this thesis: On the one hand, the development and the current state of Bergkamen's orchard meadows was recorded and examined, which in the history of the town had only taken place once in 1990. On the other hand, this work served to review the minimum criteria set by the Landesamt für Natur, Umwelt und Verbraucherschutz (LANUV) for the protection of orchard meadows and pastures.

Paul David Grünhofer's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rheinische Friedrich-Wilhelms-Universität Bonn in the year 2019.

Title:

Formation and chemical composition of suberin in poplar roots

Grünhofer analysed spatiotemporal suberin deposition in poplar roots and its chemical composition. Most parts of the results comprise control as well as osmotic stress conditions.

Plants employ suberization of root tissue as mechanism of protection against various biotic and abiotic environmental stresses. The tissue-specific formation of suberin under control and stress conditions has been investigated by use of in-vitro tissue culture, hydroponics, fluorescence microscopy and gas chromatography. The main focus of this thesis was to establish a scientifically standardized and reproducible method to grow and treat poplar roots with a variety of different stresses, in order to lay a solid foundation for future research. In addition to that it could already be shown by use of fluorescence microscopy that a treatment of the roots with a mild osmotic stress ( 0.4 MPa) resulted in a shift of the onset of suberization towards the root tip, if compared to control conditions. An analytical preparation and examination of the harvested roots by gas chromatography showed a remarkable overlap of the suberin composition to that of the commonly used model organism Arabidopsis thaliana. A quantitative evaluation to answer the question if the mild osmotic stress in fact does induce an increased suberization of the root tissue could not be answered within this work due to limited time. However, answering this question as well as the examination of more severe osmotic stresses (-0.6 MPa and -0.8 MPa) and the treatment of roots with salt stress will follow in the seamlessly started dissertation. These topics are especially interesting due to rising temperatures in the future, which will make water (represented by osmotic stress) and thereby caused salt stress an even more prominent problem in our soils

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Paul David Grünhofer conducted this thesis at the Institute for Cellular and Molecular Botany (IZMB) in the group of Prof. Dr. Lukas Schreiber.

Nicola Schmidt s Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Technical University Dresden in the year 2019.

Title:

Characterisation of the endogenous phytopararetrovirus beetEPRV3 in the sugar beet genome (Beta vulgaris), a new member of the florendoviruses within the Caulimoviridae family

For the first time, the three endopararetrovirus families within the sugar beet genome were described and analysed focusing on the family beetEPRV3. The element structure turned out to be characteristic for the respective beetEPRV family, pointing to specific evolutionary scenarios. Further, the viral sequences were found to be located within highly AT-rich heterochromatin, which provides an explanation for lacking virulence of beetEPRVs.

Endopararetroviruses (EPRVs) are a widespread component of animal and plant genomes as a result of the integration of the viral DNA. A reactivation can cause devastating diseases, as it is known for tobacco or petunia. Using comprehensive bioinformatic methods, in this work the EPRVs within the sugar beet genome were identified and assigned to the florendoviruses, which is an abundant genus within the Caulimoviridae. The element structure was reconstructed for all three beetEPRV families. Two families (beetEPRV1 and beetEPRV3) show intact copies, whereas the third family (beetEPRV2) is arranged in a more fragmented manner. The family beetEPRV3 was furthermore analysed using molecular biological and cytogenetic methods like Southern hybridisation and fluorescent in situ hybridisation. It turned out that EPRVs belonging to this family accumulate in tight, repetitive and therefore mostly inaccessible DNA regions, allowing them to escape the host’s elimination mechanisms. These findings may help to understand how EPRVs keep their virulence in some hosts over long periods.

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Nicola Schmidt conducted this work at the chair of Plant Cell and Molecular Biology in the group of Prof. Dr. Thomas Schmidt.

Erik Pischke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rostock University in the year 2019.

Title:

The role of the leucine biosynthesis for Pb tolerance in Arabidopsis thaliana

He found out that the heavy metal lead can differentially affect the growth of ecotypes and mutants of A. thaliana and that an enzyme involved in leucine biosynthesis is essential for Pb tolerance.

Natural variance of lead tolerance was tested for different ecotypes of A. thaliana to identify molecular mechanism involved in Pb tolerance. Liquid seedling assays were performed, and root lengths were measured upon exposure to Pb. Genome wide association analysis had pointed at enzymes of leucine biosynthesis. Therefore, respective mutants were studied. They showed strong Pb hypersensitivity in comparison to the reference wildtype. A partial rescue of the lead-affected phenotype was observed when leucine was supplied to the medium. Upcoming experiments will aim at understanding the genetic and metabolic reasons for the impacts that Pb has on the leucine biosynthesis in A. thaliana.

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Erik Pischke conducted this work as external Master thesis at the University of Rostock at the Department of Plant Genetics of Prof. Dr. Renate Horn cooperation with the University of Bayreuth at the Department of Plant Physiology of Prof. Dr. Stephan Clemens.

Helen Ballasus's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Leipzig University in the year 2019.

Title: Species effects on temperature regulation mechanisms in the tree canopies at the Leipzig canopy crane

Processes controlling and affecting canopy microclimate are related to the species with its specific structural and physiological functional traits and meteorological predictors depending on vertical canopy architecture.

Melanie Kastl's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Köln University in the year 2019.

Title: Functional characterization of the Ustilago maydis organ-specific effectors: UMAG05306 and UMAG11060

Two effectors of Ustilago maydis, the causative agent of corn smut disease, were localized in planta and their (putative) targets were identified and described.

Ustilago maydis parasitizes all aerial parts of the maize plant by inducing tumour formation. In order to establish biotrophy, U. maydis secretes effectors that inhibit the plant defence responses and modulate the host metabolism. Co-immunoprecipitation experiments and localization assays with fluorescent labelled effectors were performed to functionally characterize two U. maydis effectors including UMAG5306 and UMAG11060. We have shown that both effectors are secreted during host colonization and involved in fungal virulence. Furthermore, interaction studies revealed that UMAG05306 interacts and/or modulate with plant cytoskeleton, while UMAG11060 interacts with host defence component to suppress immunity. These findings will bring more insight in how fungi interfere with the plant immune system and to understand the mechanism of susceptibility and resistance.

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Melanie Kastl conducted this work at the Institute of Botany/ Chair of Terrestrial Microbiology in the group of Prof. Dr. Gunther Döhlemann.

Every other year our DBG awards the best publication with a sum of 1000 Euros. The prize of our Wilhelm Pfeffer Foundation will only be awarded for publications published in the two previous years and must derive from a Diploma, Master or PhD thesis. The final version of the publication is relevant for the publication date.

Awardees and their paper will be introduced during the upcoming Botanik-Tagung and the awarded paper will be listed on DBG's website.

Only members of the German Society for Plant Sciences (DBG) are eligible to submit nominations; self-nominations are also accepted for this prize.

The Prize, casually speaking Best Paper Prize, can be divided. There is no right to receive the prize.

Application

The following documents should be sent for application:

• Paper (pdf file)
• Peer review comments of the journal
• Letter of reference from the academic advisor of the paper. This should also mention in which context (master, diploma or PhD thesis) this work was carried out.

Deadlines

Proposals can be submitted each year (31 March); dates are communicated via the website. Please send your application to the president of the Wilhelm Pfeffer Foundation.

Cathrin Manz's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Philipps-Universität Marburg in the year 2019.

Title: "Diversity assessment of the ectomycorrhizal genus Russula in tropical montane forests in Panama"

For the first time Manz investigated the diversity of Russula species (“brittlegills”) in the mountain rainforests of Panama. More than 45 species were discovered for the first time for Panama with many of them new to science.

The diversity of ectomycorrhizal fungi in the tropics is still largely underexplored, even though they constitute a key component of tropical montane forest ecosystems. In this study, 106 collections of the genus Russula (“brittlegills”) were collected in Chiriquí, Panama and described as fresh fruiting bodies. The samples were analysed with phylogenetic methods using the universal fungal barcode ITS. The resulting phylogenetic tree revealed a total number of 90 Russula species in Panama of which 47 species were newly recorded for this country. Among these samples are many putatively new species. A selection of four new Russula species from subsection Roseinae were analysed morphologically by light and scanning electron microscopy in the context of the master thesis. Five patterns for ectomycorrhizal partners and geographic distribution were revealed. Facing habitat loss and climate change, it is today more than ever necessary to collect and store specimens with associated data and to openly share these resources. Otherwise many species will become extinct unnoticed.

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Cathrin Manz conducted this work at the Department of Biology in the Research group mycology by Karl-Heinz Rexer.

Nora Stingl's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Philipps Universität Marburg in the year 2020.

Title: Establishment and optimization of new model organisms to study early land plant evolution

Stingl successfully established three new model organisms and optimised their cultivation conditions for future studies on the conquest of land by plants.

The establishment of new model organisms is crucial to study the water to land transition of plants, which set the fundament to nature how we know it. It is widely accepted that one group from the charophyte algae, more accurate from the ZCC paraphylum, gave rise to the ancestor of land plants. Since no model organisms have yet been established in this group, three organisms were selected as potential model organisms: Chara braunii, Spirogyra pratensis and Mougeotia scalaris. Within this work protocols for laboratory cultivation of all three organisms could be developed. Additionally, sexual reproduction of C. braunii and S. pratensis was successfully induced repeatedly and a protocol for germination of C. braunii oospores was established.

Within the land plants the bryophytes are considered sister taxons of the vascular plants and the hornwort Anthoceros agrestis is already established as a model organism. In this thesis, studies on in vitro cultivation were performed and different growth and germination behavior between axenic and non-axenic cultures could be observed.

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Nora Stingl conducted this work at the department of biology in the lab of Prof. Dr. Stefan A. Rensing.

Levke Valena Höche's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Christian-Albrechts-Universität zu Kiel in the year 2020.

Title: The combined effects of population origin and inbreeding on plant traits attracting pollinating insects

Inbreeding can have a negative impact on floral scent production and spatial flower traits. The magnitude of this effect strongly depends on the sex of plant individuals and the geographic origin of a population.

The attractiveness of a flower towards pollinators is determined by a combination of spatial and olfactory traits. Inbreeding can negatively impact these traits, and its effect can vary within a population between male and female plants, and among populations from different geographical origins.

We recorded differences in spatial and olfactory floral traits in outcrossed and inbred, female and male individuals of the dioecious plant Silene latifolia from eight European and eight North American populations. Additionally, visitation rates by crepuscular pollinators were quantified.

Inbreeding reduced the number and size of the flowers as well as the amount of lilac aldehydes that are essential for chemical communication with crepuscular moths. This effect was partially more pronounced in female than male individuals and varied between populations of different origins. However, this effect was not reflected in the pollinator visitation rates, which had only been investigated during a small timeframe in late summer for logistical reasons. Our results support that inbreeding has the potential to lessen the attractivity of a flower towards pollinating insects, and that sex-specific selection and the evolutionary history of a population shape the underlying genetic architecture.

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Levke Valena Höche conducted this work at the Institute for Ecosystem Research / Department Geobotany, supervised by Dr. Karin Schrieber.

Joelle Kröll's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Innsbruck University in the year 2020.

Title: Allopolyploidy, introgression and morphological differentiation in the Pyrenean endemic Saxifraga pubescens of awarded thesis

Multiple data sources unravel inconspicuous diversity in a Pyrenean high mountain endemic: from one to two species, genome duplications and recurring hybridization

Hybridization is an important evolutionary force in plants, which can either lead to reduction of differentiation through introgressive hybridization or increase in diversity due to the appearance of a new evolutionary entity through hybrid speciation. For the latter to take place, hybrids need to overcome two major challenges, i.e. hybrid sterility and backcrossing with the parental lineages. One way to overcome both of these problems is allopolyploidy. Recurrent hybridization with co-occurring species has been reported in the Pyrenean endemic Saxifraga pubescens, but its evolutionary consequences as well as its link to polyploidy remain to date uncertain. Although two subspecies with allopatric distributions are recognised, i.e. S. pubescens subsp. pubescens and S. pubescens subsp. iratiana, some contradictory reports indicate overlapping distributions. Since the species is protected in some areas both in Spain and in France, it is necessary to clarify the intraspecific systematics of S. pubescens. For this purpose, we integrate morphological, relative genome size and molecular data from RADseq and plastid DNA sequencing to infer the evolutionary and biogeographical history of the species, with special focus on hybridization and polyploidy and to propose a congruent systematics framework. We observe both occasional occurrences of hybrids in populations of S. pubescens as well as entirely hybrid populations. Homoploid hybridization seems to generate the occasional hybrids, while the entirely hybrid populations consist of allopolyploids, which indicates fertility of the hybrids and their potential to create hybrid lineages (and eventually species). Morphology allows the proper identification of the two subspecies as well as the hybrids, with the exception of individuals with imbalanced introgression. In addition, the molecular data resolve both subspecies as monophyletic, but the species itself as polyphyletic and indicate that the two subspecies are consistently well-differentiated entities, and should be recognised as two separate species.

The Master thesis of Joelle Kröll was published (in : https://diglib.uibk.ac.at/ulbtirolhs/download/pdf/5341778?originalFilename=true

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Joelle Kröll conducted this work at the Institute for Botany in the working group Evolutionary Systematics of Univ.-Prof. Mag. Dr. Peter Schönswetter and Ass. Dr. Pau Carnicero.

Johanna Knab's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) in the year 2020.

Title: Analysis of CNGCs in Physcomitrium patens and generation of optogenetic lines and a pH marker for live-cell imaging

Local Ca2+-import trough CNGC channels appears to modulate tip growth in moss (Physcomitrium patens) protonemata and can be investigated using a newly established optogenetic system.

In plants, "cyclic nucleotide-gated channels" (CNGCs) regulate numerous biological processes ranging from development to tip growth and immune responses. Eight CNGCs have been identified in the moss Physcomitrium patens, whose functions are largely unexplored. By contrast, in the model plant Arabidopsis thaliana essential functions of different CNGCs in the tip growth of root hairs and pollen tubes have already been established. In order to investigate the role of CNGCs in tip growth in moss, P. patens CNGC knock-out lines were generated using CRISPR/Cas methodology. Four different cngc single KO lines, two cngc double KO lines and one cngc triple KO line were established. Despite extensive efforts, it was not possible to generate KO lines disrupted in the expression of the remaining four CNGCs, indicating essential functions of these channels in moss. Investigation of the established cngc KO lines has shown that three P. patens CNGCs in fact modulate tip growth in protonemata. cngc-b, cngc-c, and cngc-h single KO lines, as well as two of the cngc double KO lines, showed significantly increased elongation of protonemal cells. This effect was particularly pronounced in the cngc-b / cngc-c double knockout line, which indicates additive functional interactions between CNGCc and CNGCb.

Furthermore, experiments were performed to establish an optogenetic system in P. patens. Optogenetics is a cell biological method, which enables the control of processes in living cells by light pulses using light-sensitive proteins. In cooperation with Prof. Dr. Nagel from the University of Würzburg, transgenic P. patens lines were generated expressing a recombinant channel rhodopsin tagged with a green fluorescent protein (ChR-2-XXL::GFP). Similar channel rhodopsins have already been used successfully in neurobiology to generate light-induced action potentials. Channel rhodopsin-2 is a light-controlled cation channel from the unicellular green alga Chlamydomonas reinhardtii. On the basis of this protein, Prof. Dr. Nagel developed the ChR-2-XXL channel, which allows blue-light-controlled local stimulation of Ca²⁺ import through the plasma membrane. This channel was successfully expressed for the first time in P. patens, and was found to be targeted to plasma membrane of protonemata cells, an important prerequisite for its function in Ca²⁺ import. In addition, a dioxygenase fused to a chloroplast targeting sequence was demonstrated to be imported into chloroplasts, where this enzyme can synthesize retinal using ß-carotene as a precursor. Retinal is essential for the function of the ChR-2-XXL channel. With this system it should now be possible to examine effects on tip growth of local cell depolarization triggered by blue light stimulation.

In the “Cell Biology Divison” at FAU, the role of Rac/Rop-dependent signal cascades in the control of tip growth in plants has been investigated for many years. The work described here represents an excellent basis for the future investigation of functional interactions between Rac/Rop- and Ca²⁺-dependent signal cascades in the moss P. patens.

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Johanna Knab conducted this work in the FAU Division of Cell Biology under the supervision of Dr. Maria Ntefidou in the team of Prof. Dr. Benedikt Kost.

Lara Hoepfner's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Westfälische Wilhelms-Universität Münster in the year 2020.

Title: Function of protein N-glycosylation in flagella mediated cell gliding

Altered N-glycan maturation of flagella membrane proteins impacts adhesion to solid surfaces however does not impede the cells gliding ability.

The biflagellate Chlamydomonas reinhardtii is a well-known model organism in research on cilia and flagella. Via their two flagella, cells are able to adhere to and glide along solid surfaces thanks to N-glycosylated membrane proteins such as flagella membrane glycoprotein FMG1-B.

Taking advantage of mass spectrometry and TIRF microscopy mutants with altered N-glycosylation were analyzed regarding changes in their flagella proteome as well as their ability to adhere and glide. Further the particular role of FMG1-B in respective dynamics was examined by characterization of two FMG1-B knock down mutants.

Altered N-glycosylation decreases the adhesion force of flagella to a surface, however, this has no impact on flagella protein targeting or the ability to glide. Further it could be shown that FMG1-B is not the only N-glycosylated protein involved in flagella membrane adhesion and gliding in contrast to the current model.

In future further N-glycosylation mutants will be analyzed regarding their ability to adhere and glide and the role of further candidate proteins involved in adhesion and gliding besides or instead of FMG1-B will be analyzed.

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Lara Hoepfner conducted this work at the institute for plant biochemistry and biotechnology in the working group of Prof. Dr. Michael Hippler.

In the year 2020 DBG's representatives at the universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Claudia Banse (Humboldt Universität Berlin)
Hämbindung an der GBP sorgt für Feedback-Regulation in der Tetrapyrrolsynthese

Susanne Elisabeth Bleser (Johannes Gutenberg-Universität Mainz)
Characteristics of CAM-photosynthesis and anatomic-physiological features of leaves in Aeonium (Crassulaceae)

Nicole Graumann (Universität Bielefeld)
Gene editing mittels CRISPR/Cas9-vermittelter Mutagenese in der Grünalge Volvox carteri

Levke Valena Höche (Christian-Albrechts-Universität zu Kiel)
The combined effects of population origin and inbreeding on plant traits attracting pollinating insects
more in the -> summary with images

Lara Höpfner (Westfälische Wilhelms-Universität Münster)
Function of protein N-glycosylation in flagella mediated cell gliding
more in the -> summary and image

Johanna Knab (Friedrich-Alexander-Universität Erlangen-Nürnberg, FAU)
Analysis of CNGCs in Physcomitrium patens and generation of optogenetic lines and a pH marker for live-cell imaging
more in the -> summary with image

Joelle Kröll (Universität Innsbruck)
Allopolyploidy, introgression and morphological differentiation in the Pyrenean endemic Saxifraga pubescens
more in the -> summary with images

Elena Lesch (Rheinische Friedrich-Wilhelms-Universität Bonn)
Evolution of moss RNA editing factors and their functions tested in a variety of model systems
more in the -> summary with image

Fabian Munder (Universität Hamburg)
Elucidating the Mechanism of Protein Translocation into Peroxisomes: Biophysical, Structural and in vivo Characterization of two Peroxisomal Biogenesis Proteins from Arabidopsis thaliana

Mara Schultz (Universität Rostock)
Die Rolle des Proteins HliR1 in Synechocystis sp. PCC 6803 bei der Stressantwort bei Starklichtverhältnissen
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Nora Stingl (Philipps Universität Marburg)
Successful cultivation of the new model organisms Chara braunii, Spirogyra pratensis and Mougeotia scalaris in the lab and discovery of different growth behavior of various Anthoceros agrestis strains
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Johanna Wiedener (Universität Leipzig)
Investigation of a mixed species cultivation concept for a continuous photosynthesis-driven hydrogen production
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Mara Schultz's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rostock University in the year 2020.

Title: The role of the small protein HliR1 in Synechocystis sp. PCC 6803 during high light stress

Schultz characterized the physiological role of the recently annotated small protein HliR1 and detected its participation in the high light stress response in Synechocystis sp. PCC 6803.

The small protein HliR1 was newly annotated by Baumgartner et al. (BMC Microbiol 28:2016) in the genome of Synechocystis, where hlir1 is located in front of the gene for superoxide dismutase (SOD). SOD is involved in the removal of reactive oxygen species in the cell, which occur in particular in the case of strong light stress.

To analyze the physiological role of HliR1 in Synechocystis, several mutants were available in which the protein-coding or RNA-coding part of hliR1 was deleted. Furthermore, a strain in which HliR1 was expressed in the mutant was examined. Schultz characterized these strains phenotypically, biochemically and molecular biologically with regard to growth under different conditions. In addition, I aimed to detect interactions of HliR1 with other proteins.

The physiological investigations showed that HliR1 plays an important role during high light stress. The mutant with the protein-coding sequence deleted could not grow in strong light, while the expression of hliR1 in this mutant abolished the phenotype. However, neither changes in the SOD activity nor an HliR1-SOD interaction could be detected that would have explained this phenotype. Investigation of protein-protein interactions suggests that HliR1 may interact with various proteins involved in building and repairing photosystem II. This finding suggests that HliR1 may play a role in the repair of photosystem II under high light stress.

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Mara Schultz conducted this work at the Institute for life sciences in the working group of Prof. Dr. Martin Hagemann.

Johanna Wiedener's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Leipzig University in the year 2020.

Title: Investigation of a mixed species cultivation concept for a continuous photosynthesis-driven hydrogen production

A mixed species cultivation using a photosynthetic cyanobacterium and an oxygen consuming heterotrophic bacterium enables light-driven and continuous hydrogen production from water.

Hydrogen is considered as the energy carrier of the future. In addition to a technical generation of hydrogen by electrolysis of water using renewable energies (solar/wind power), biological approaches are also possible. Promising are cyanobacteria, which also can split water by the means of light to ‘’win’’ electrons for biosynthesis. This process is known as oxygenic photosynthesis. In cyanobacteria the electrons obtained from water splitting can alternatively "flow" into the enzymatic synthesis of hydrogen.

The present work deals with the light-driven hydrogen production of the model strain Synechocystis sp. PCC 6803 – particularly to the dilemma that the hydrogenases necessary for hydrogen production, obtain electrons from photosynthesis but are at the same time inactivated by the oxygen also generated during photosynthesis. In this master thesis, the milieu was kept anaerobic for the first time by co-cultivating Synechocystis with a heterotrophic bacterium. Thereby a hydrogen synthesis was achieved that could be measured over several hours. It could be proven that the electrons for hydrogen synthesis indeed originate from photosynthetic water splitting. Furthermore, the observations could also be transferred to an alternative cultivation concept: a bacterial biofilm. 'Multi-species' biofilms represent the natural lifestyle of microorganisms and offer the advantage of improved tolerance to unfavorable environmental conditions. From a technical point of view, they allow a long-term, stable cultivation of microorganisms. If sufficient nutrient sources are present, they can generate all their needed elements by themselves and are also able of self-regeneration. In biofilms a significant hydrogen production was documented even after several weeks. It was proven that it is in fact the cyanobacterial partner that produces this hydrogen. Although many problems still need to be solved, this work has taken the biological approach of hydrogen production a significant step towards application.

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Johanna Wiedener conducted this work at the Helmholtz-Centre for Environmental Research (UFZ) Leipzig in the department Solar Materials of Prof. Andreas Schmid under supervision of PD Dr. Stephan Klähn.

Elena Lesch's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rheinische Friedrich-Wilhelms-Universität Bonn in the year 2020.

Title: Evolution of moss RNA editing factors and their functions tested in a variety of model systems

The expression of moss RNA editing factors in evolutionary distant model species allows new insights into their mode of operation and into the co-evolution with their targets.

Plant RNA editing induces site-specific conversion of cytidines (C) into uridines (U) in plant chloroplasts and mitochondria. RNA-binding pentatricopeptide repeat (PPR) proteins have the key role of binding to the RNA targets and converting Cs into Us. PPR78 is such a nuclear encoded C-to-U RNA editing factor that targets two mitochondrial RNA editing sites in the cox1- and in the rps14-mRNA in the model moss Physcomitrium patens. Many other moss species were surveyed for the presence of PPR78 and it was found to be conserved even in species, where editing is extremely reduced or not needed at all because Us are already present at these positions (corresponding to thymidine in the genes at the DNA level; see figure). Suspecting a yet unrecognized target site for PPR78 we could successfully predict bioinformatically and subsequently confirm a further editing target in the ccmFN RNA. Moreover, we succeeded to transfer PPR78 into the bacterium Escherichia coli, which was recently established by us as a bacterial model system for RNA editing (Oldenkott et al.[1]).  We found that PPR78 could not only perform C-to-U conversions at the previously known editing sites in cox1 and rps14 but also at the newly identified site in ccmFN. Altogether the new data are promising for future attempts to specifically introduce changes to RNA transcript sequences in diverse organisms.

[1] Oldenkott, B., Yang, Y., Lesch, E., Knoop, V., Schallenberg-Rüdinger, M. (2019): Plant-type pentatricopeptide repeat proteins with a DYW domain drive C-to-U RNA editing in Escherichia coli. Commun Biol 2, 85. https://doi.org/10.1038/s42003-019-0328-3

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Elena Lesch conducted this work at the Institute of Cellular and Molecular Botany in the „Molecular Evolution“ lab under the supervision of Prof. Dr. Volker Knoop and Dr. Mareike Schallenberg-Rüdinger.

In the year 2020 DBG's representatives at the universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Paul Buschbeck (Johannes Gutenberg-Universität Mainz)
Cloning and functional characterization of enzymes involved in the violaxanthin synthesis of chromalveolates
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David Clara (Universität Innsbruck)
Do natural seed bacterial microbiota play a role in soybean germination?
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Josephine Dieckmann (Universität Rostock)
Ist die 2-Phosphoglycolat vermittelte Regulation der ADP-Glucose-Pyrophosphorylase an der Bewegung der Stomata beteiligt?

Maxim Faroux (Universität Kiel)
The aquaporin PIP2;1 as a potential interaction partner of PSKR1
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Maleen Hartenstein (Friedrich-Alexander-Universität Erlangen-Nürnberg)
Examination of interspecific plasmodesmata and anatomical characterization of infection sites between Cuscuta reflexa and its host plants
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Anna-Sophie Hawranek (Universität Wien)
The impact of recurrent origins and gene flow on the genetic structure of allopolyploid marsh orchids (Dactylorhiza, Orchidaceae)
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Jessica Klekar (TU Dresden)
Karyotype evolution within the genus Beta
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Madita Knieper (Universität Bielefeld)
The role of cyclophilin CYP20-3 in the redox regulatory network of chloroplasts
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Julia Metzsch (Justus-Liebig-Universität Gießen)
Investigation into the status Jurinea cyanoides (L.) Rchb., in a nature conservation context
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Kristina Munzert (Philipps-Universität Marburg)
Characterisation of mutants suppressing the hypersusceptibility of starch-free Arabidopsis thaliana to Colletotrichum higginsianum
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Lea-Franziska Reekers (Westfälische Wilhelms-Universität Münster)
A detailed localization analysis of enzymes involved in Lewis a-epitope formation in Arabidopsis thaliana
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Ronja Rüdel (Salzburg University)
Experimental evolution of zinc tolerance in Pseudomonas syringae infecting zinc accumulating plants
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Michelle Schlösser (Bonn University)
Characterization of the ER-localized glutaredoxins GRXC3 and GRXC4 in Arabidopsis
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Sebastian Triesch (Heinrich-Heine-Universität Düsseldorf)
Evolution of differential gene expression patterns in Brassicaceae with C₃-C₄ photosynthesis
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Dorothea Vesely (Leipzig University):
Investigation of terpene biosynthesis in cyanobacteria
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Raphael von Büren (Universität Basel)
Contrasting habitat requirements of the abundant alpine tussock graminoids Carex curvula und Nardus stricta
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Julia Metzsch's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Justus Liebig University Giessen in the year 2021

Title: Investigation into the status Jurinea cyanoides (L.) Rchb., in a nature conservation context

This work analyses the reasons for the decline in the thistle Jurinea cyanoides and should help to protect this species.

Jurinea cyanoides (L.) Rchb. is a native and threatened species in Germany, whose populations continue to decline despite various conservation measures. This paper therefore aims to provide an overview of the status of the species and to identify possible reasons for the loss of J. cyanoides.

For this purpose, a population genetic analysis using AFLP (Amplified Fragment Length Polymorphism) was performed. A comparative site characterization was made based species lists. Finally, conservation measures were evaluated.
The results showed that a decline of J. cyanoides due to population genetic reasons could be excluded. The site-specific characterizations measures did not provide clear results. Furthermore, grazing by sheep and donkeys was a positively evaluated measure, while fencing of the areas is rather not recommended.

The results obtained here should contribute to the protection of the endangered species J. cyanoides.

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Julia Metzsch conducted this work at the Institute of Botany in the research group of Prof. Dr. Wissemann (Justus-Liebig-Universität Gießen) an in cooperation with Prof. Dr. Birgit Gemeinholzer (Universität Kassel).

Maleen Hartenstein's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Friedrich Alexander University Erlangen-Nürnberg in the year 2021

Title: Examination of interspecific plasmodesmata and anatomical characterization of infection sites between Cuscuta reflexa and its host plants

The parasitic plant Cuscuta reflexa manipulates its host and induces the formation of interspecific plasmodesmata to gain unrestricted access to the assimilates of its host plant.

Plasmodesmata are essential for cell-cell communication and the exchange of macromolecules between neighboring cells and tissues in higher plants. The parasitic plant Cuscuta reflexa (engl. dodder) forms symplastic connections to its host plants via plasmodesmata. C. reflexa is a shoot parasite without roots and leaves and completely dependent on nutrients of its hosts. To gain access to host plant assimilates, C. reflexa penetrates the host tissue with haustoria. Searching hyphae grow out of the haustoria and establish a direct connection to the vascular tissue oft the host plant via plasmodesmata. Therefore, C. reflexa is being used as a model to study newly formed interspecific plasmodesmata.

In this work, the anatomy of the contact sites between the searching hyphae of C. reflexa and the host phloem was investigated. For this purpose, pseudo-Schiff propidium iodide (PS-PI)-staining was established as a method for the visualization of interspecific contact sites. PS-PI staining was used to visualize the characteristic hand structure of searching hyphae of C. reflexa that specifically connected to host phloem cells. For further studies of the infection sites, different marker lines were infected with C. reflexa. It was demonstrated that C. reflexa induces the formation of new phloem tissue in the host. Infection of another marker line revealed that C. reflexa induces the formation of new plasmodesmata in the phloem and cortical tissue of the host. Furthermore, it was shown that C. reflexa connects symplastically to the cher1 mutant, although cher1 is impaired in the formation of complex plasmodesmata. Last, it was demonstrated that upon the infection with C. reflexa, the expression of several plasmodesmata-associated genes of A. thaliana is induced.

However, the signal that triggers the formation of plasmodesmata between host and parasite is still unknown and thus subject to future investigation.

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Maleen Hartenstein conducted this work at the Division of Molecular Plant Physiology under the supervision of PD Dr. Ruth Stadler in the group of Prof. Dr. Markus Albert.

Anna-Sophie Hawranek's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Vienna University in the year 2021

Title: The impact of recurrent origins and gene flow on the genetic structure of allopolyploid marsh orchids (Dactylorhiza, Orchidaceae)

Using genomic data, advanced bioinformatic analyses and coalescent approaches, this thesis elucidates the evolutionary history of three sibling allotetraploid marsh orchids.

Whole genome doubling, resulting in polyploidy, has been important for the evolution of plants and other organisms. Marsh orchids are Eurasian species that are often threatened due to the scarcity of their preferred habitats – five of these are the subject of this study: the three sibling allotetraploids Dactylorhiza majalis, D. purpurella and D. traunsteineri together with their parental species, the diploids D. fuchsii and D. incarnata.

The presented study relies on a reference genome of Dactylorhiza incarnata (the paternal species) to analyse genome-wide sequences of over 200 individuals of the three tetraploid species. Specific polyploid-adapted bioinformatic programs enabled addressing population genetic questions by considering the tetraploid set of chromosomes.

As seen in population genetic cluster analyses, the genetic structure of allopolyploid marsh orchids is influenced by geographical isolation on the one hand, and overlapping distribution areas on the other. Further, significantly more gene flow goes from the diploid parental species to the allopolyploids than vice versa. Also, within the allopolyploids a large amount of genetic material is exchanged. Therefore, the three focal polyploid species are not yet fully reproductively isolated from each other. Nevertheless, at least three different gene pools are found, broadly assignable to the three described species.

Despite their frequency across (macro)evolution, the actual formation of polyploids are rare events. Polyploid populations initially have small sizes and little genetic variation. The narrow gene pool can get expanded by hybridisation with relatives and this seems to be also the case in marsh orchids.

A look further back into the past discloses for the investigated polyploids three independent origins from the same parental species within interglacials (i.e., warmer periods) during the Quaternary. Demographic modelling confirms previous results regarding the succession of allopolyploids: with approx. 594,000 years D. majalis is found to be the oldest of the three species. It is a vigorous, large orchid, distributed in continental Europe. Dactylorhiza traunsteineri is estimated to be approx. 430,000 years old. This species shows a disjunct distribution area with an allopatric zone (i.e., it occurs without the other two allopolyploids) in Scandinavia, a sympatric area with D. majalis in the Alps and a second sympatric area with D. purpurella on the British Isles. This type of distribution can promote high genetic variability and could be reflected in the higher effective population size as compared to D. majalis. The youngest of the three analysed species is D. purpurella with approx. 3,100 years. This species occurs on the British Isles and parts of Western Scandinavia.

The chosen methodology is based on a Bayesian approach of assigning the polyploid genomic sequences to their respective diploid origins. This enabled analyses of each of the subgenomes apart from each other as diploid data sets. The developed bioinformatic scripts for data processing are also provided in the thesis’ appendix.

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Anna-Sophie Hawranek conducted this work at the Department of Botany and Biodiversity Research in the working group of Assoc.-Prof. Dr. Ovidiu Paun.

Read more in Hawranek's thesis: https://plantgenomics.univie.ac.at/fileadmin/user_upload/p_plantgenomics/News/Hawranek_DactThesis.pdf

Jessica Klekar's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at TU Dresden in the year 2021

Title: Karyotype evolution within the genus Beta

By barcoding of the chromosomes of sugar beet and closely related species, it was possible to detect major structural changes as species boundaries.

Cytogenetics, as an important branch of genetics, deals with chromosome structure and composition in order to link these to phenotypic phenomena. In most plants, chromosomes cannot be distinguished on the basis of simple staining so that karyotyping is not readily possible. To address this lack for sugar beet (Beta vulgaris) and related wild beets, we developed a two-colour barcode for karyotyping the nine chromosome pairs of sugar beet through fluorescent in situ hybridization (FISH) and applied it to the genomes of closely related species. In addition to confirming the pericentric inversion on chromosome 5 of Beta patula, a paracentric inversion on chromosome 7 of Beta macrocarpa was identified using an altered barcode. The knowledge gained about the structural chromosomal differences between the species should not be understood exclusively as species boundaries, but may also be indications of the high heterogeneity of the wild species. This could become relevant for breeding if resistance genes to diseases can be identified on the affected chromosomes of the wild species, which are not (or no longer) present in the cultivated sugar beet.

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Jessica Klekar conducted this work at the Chair of Plant Cell and Molecular Biology in the research group of Dr. Tony Heitkam.

Kristina S. Munzert's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Kristina Munzert Philipps University Marburg in the year 2021

Title: Characterisation of mutants suppressing the hypersusceptibility of starch-free Arabidopsis thaliana to Colletotrichum higginsianum

Munzert mapped Arabidopsis suppressor mutants of carbohydrate-dependent pathogen hypersusceptibility and characterised alterations in their defence responses.

Starch-free Arabidopsis plants show a strongly increased susceptibility to the hemibiotrophic pathogen C. higginsianum, as the lack of carbohydrate availability limits the defence response of the plant. This affects, for example, the composition of the plant cell wall as a penetration barrier, as well as the production of secondary metabolites for pathogen defence. Using a forward genetic approach, EMS-mutagenized starch-free plants were identified that showed suppression of hypersusceptibility. The selected mutants were examined via biochemical analysis and infection assays. It was shown that the increased resistance was partially established in the early biotrophic interaction with C. higginsianum and that there were changes in cell wall composition, as well as in the production of secondary metabolites. The specific changes in pectin and hemicellulose polymers of the cell wall could directly affect the penetration success of C. higginsianum or influence the induced defence response of the plant. Elevated levels of the phytohormone salicylic acid and the phytoalexin camalexin were detected partially independent of pathogen infection and could indicate priming of the mutants with defence compounds prior to infection and could account for early established resistance. In addition to physiological characterization, causative mutations in the genome of the selected mutants were mapped by next-generation sequencing.

Anthracnose caused by Colletotrichum spp. is a severely yield-reducing plant disease, the effects of which could be mitigated by a better understanding of plant defences following Colletotrichum spp. infestation.

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Kristina S. Munzert conducted this work at the Department of Biology of Philipps University of Marburg under supervision of Dr. Timo Engelsdorf in the group of Prof. Dr. Lars Voll.

Ronja Rüdel's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Paris Lodron University Salzburg in the year 2021

Title: "Experimental evolution of zinc tolerance in Pseudomonas syringae infecting zinc accumulating plants"

This study provides evidence that pathogens can rapidly evolve higher zinc tolerances in vitro and are therefore able to infect plants, which have accumulated increased concentrations of zinc. This result supports the Elemental Defence Hypothesis and reveals a connection between plant pathogens and the evolutionary trait of metal hyperaccumulation in plants.

The enhanced uptake and storage of heavy metals in plants may function as a protection mechanism of the plant against herbivores or pathogens, which is known as the “elemental defence hypothesis”. This study aimed to investigate the ability of plant pathogens to coevolve with hyperaccumulating plants by adapting to altered metal concentrations.

In this study, in vitro experimental evolution of a Pseudomonas syringae pv. maculicola standard laboratory strain was performed to possibly evolve strains exhibiting increased zinc tolerance. Further, in vitro assessment of zinc tolerance of the evolved bacterial strains was conducted to characterize enhanced zinc tolerances. This was followed by in planta infection assays to investigate the ability of the evolved, zinc tolerant bacterial strains to infect the zinc accumulating plant Noccaea caerulescens.

The results of this study provide evidence that it is possible to evolve strains towards higher zinc tolerance in only few rounds of experimental evolution. The evolved strains were able to infect plants, which had accumulated intermediate to high concentrations of zinc, while the original Pseudomonas syringae strain showed reduced growth rates in those plants. These results support the “elemental defence hypothesis” and reveal coevolutionary processes in plant pathogens adapting to metal hyperaccumulating plants.

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Ronja Rüdel conducted this project under supervision by Dr. Anja Hörger in the group of Prof. Hans-Peter Comes at the Department of Biosciences at the University of Salzburg.

Sebastian Triesch's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Heinrich Heine University Düsseldorf in the year 2021

Titl: Evolution of differential gene expression patterns in Brassicaceae with C₃-C₄ photosynthesis

C₃-C₄ intermediate plants provide an insight into the evolution of the highly complex C₄ photosynthesis. In this work, genetic mechanisms underlying C₃-C₄ intermediate photosynthesis were investigated.

Photosynthesis, the central pathway for energy production in plants, suffers from the affinity of the enzyme Rubisco to atmospheric oxygen. When Rubisco reacts with oxygen, toxic by-products are formed. Therefore, over 60 times independently in evolution, the so-called C₄ photosynthesis, a more efficient form of plant metabolism, arose. C₄ photosynthesis is highly complex and occurs in only a few important crop plants. Plants that are “on the evolutionarily path” to C₄ photosynthesis can help to better understand its evolution and find the genetic mechanisms that underlie it. These C₃-C₄ intermediate plants include, for example, Diplotaxis tenuifolia, also known as rocket. 

To investigate the genetic underpinnings of C₃-C₄ intermediate photosynthesis, the genomes of over 20 species from the crucifer family (Brassicaceae) were used. Specifically, genetic traits that correlate with the occurrence of the C₃-C₄ intermediate phenotype were sought.

An important strategy in the evolution of C₃-C₄ intermediate photosynthesis is the cell-specific activity of certain genes. In this work, it was shown that a gene that plays an important role in photosynthesis is active in C₃-C₄ plants only along the leaf veins (see figure). In C₃ plants, however, the gene is active throughout the leaf. At the genetic level, it was shown that a mobile DNA element (transposon) is selectively present in the regulatory region (promoter) of the gene only in C₃-C₄ plants. Interestingly, in three different species with C₃-C₄ intermediate photosynthesis, different types of structural variation can be found. Thus, in the evolution of C₃-C₄ photosynthesis, the same genetic mechanisms were probably found independently to shift the activity of the target gene specifically along the leaf veins.

The results of this work not only show how evolution finds similar genetic solutions to existing problems; they also point to possible starting points for genetic modification of plants. Highly complex phenotypes such as C₄ photosynthesis can be introduced into crop plants once the basic genetic mechanisms that led to the natural evolution of the traits are understood.

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Sebastian Triesch conducted this work the Institute of Plant Biochemistry (Cluster of Excellence on Plant Sciences, CEPLAS) led by Prof. Dr. Andreas P. M. Weber.

Paul Buschbeck's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Johannes Gutenberg University Mainz in the year 2021.

Title: Cloning and functional characterization of enzymes involved in the violaxanthin synthesis of chromalveolates

Transient implementation of a novel violaxanthin synthesis pathway in tobacco leaves by means of heterologous expression of algal enzymes resulted in a doubling of violaxanthin content compared to wild-type tobacco.

The superphylum Chromalveolata comprises a polyphyletic group of algae whose plastids originally arose from secondary endosymbiosis with an early red alga. With respect to the photosynthetic apparatus of chromalveolates, one of the most striking features compared to green algae or land plants is the high pigment diversity. This diversity is particularly striking for the carotenoids, which belong to the lipophilic pigments. An obligate intermediate for the biosynthesis of many important carotenoids of chromalveolates is the xanthophyll violaxanthin.

The synthesis of violaxanthin in land plants proceeds via the hydroxylation of β-carotene to zeaxanthin and the subsequent epoxidation of zeaxanthin to violaxanthin. Interestingly, previous studies led to the hypothesis that some chromalveolates may have an alternative violaxanthin biosynthetic pathway that differs from the pathway of land plants.

To investigate this hypothesis, in vivo characterizations of the substrate specificity of putative carotenogenic enzymes from different chromalveolates were performed. For that purpose, the corresponding algal genes were cloned and transiently expressed in tobacco leaves using Agrobacterium-mediated transformation. In tobacco leaves a certain amount of β-carotene is accessible to the heterologous enzymes when they are targeted to the plastids as the site of endogenous carotenoid biosynthesis. Thus, β-carotene could serve as a substrate of the heterologous enzymes and as an educt for novel carotenoid biosynthesis pathways catalyzed by the algal enzymes. Based on the pigment stoichiometries in the transformed tobacco leaves measured by HPLC, the substrate specificity of the heterologous enzymes could be deduced.

By this means, an alternative violaxanthin biosynthesis pathway catalyzed by algal enzymes was transiently implemented in tobacco leaves, bypassing zeaxanthin as an intermediate. Notably, the violaxanthin content in the transformed tobacco leaves was more than doubled compared to the wild type. Determination of the substrate specificities of the corresponding algal enzymes provided evidence that chromalveolate algae such as the well-known diatom Phaeodactylum tricornutum possess the genetic makeup to catalyze an alternative violaxanthin synthesis pathway that avoids the formation of zeaxanthin as intermediate. This finding opens further interesting avenues of research, such as the question of the selection pressure that led to the evolution of an alternative violaxanthin synthesis pathway in chromalveolates.

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Paul Buschbeck conducted this work at the Institute of Molecular Physiology in the group of Dr. Martin Lohr.

Raphael von Büren's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Basel University in the year 2021

Title: Contrasting habitat requirements of the abundant alpine tussock graminoids Carex curvula and Nardus stricta

Winter frost (due to missing snow cover) and different frost resistance explain the occurrence of Carex curvula and Nardus in the alpine belt. This extends the understanding of the fundamental niche of the two most abundant graminoid species in the Alps.

Aim: “Where and why does a species exist” represents a fundamental question in plant ecology. Nevertheless, the actual physiological range limits of alpine plant species remain largely unexplored. I aim at identifying the cold range limits of the two most abundant tussock-forming graminoid species on acidic soils above the climatic treeline in the European Alps: Carex curvula ssp. curvula (Cyperaceae) and Nardus stricta (Poaceae).

Methods: Soil temperatures (-3 cm) and other environmental variables were measured in situ at high spatial-temporal resolution, resulting in 115 well-characterized microsites (thermal conditions, snow cover duration, soil chemistry, vegetation composition, Landolt indicator values). By combining these observational data with freezing resistance (electrolyte leakage, tetrazolium vital staining, regrowth capability) at 38 of these microsites, I tried to explain the two graminoids’ distribution mechanistically.

Results: Carex and Nardus clearly segregated along different microsites. Neither soil chemistry (pH, C/N-ratio, phosphorus), nor growing degree hours and duration of the growing season (thus snowmelt date) played a decisive role. The occurrence was strongly affected by low soil temperature minima in winter. Carex occurred at sites with and without protecting snow cover and resisted low soil temperatures (-13 °C). Nardus was absent at microsites with short snow cover duration and soil minimum temperatures below -5 °C. Electrolyte leakage analyses unveiled higher freezing resistance of Carex leaves (mean LT50: -16.1 °C) compared to Nardus leaves (-13.3 °C) during the growing season. Towards the end of the growing season, foliar hardening was observed in both species. Tetrazolium vital staining revealed higher freezing resistance in young (belowground) shoots of Carex compared to Nardus, with shoot apices tolerating lowest temperatures. However, a vital shoot apex alone cannot ensure regrowth after winter. Crucial were intact vascular tissues (phloem, xylem) and roots, all less tolerant to freezing than apical tissues.

Main conclusions: Cold range limits were defined by thermal extreme values (sharp thresholds for survival) and not through gradual effects of soil temperature (thermal growth constraints). The study highlights the importance of incorporating (I) ground-truth microclimatic data in topographically diverse alpine environments as well as (II) a species’ freezing resistance to explore its survival limit at the cold edge of the fundamental niche.

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Raphael von Büren conducted this work at the Department of Environmental Sciences in the Physiological Plant Ecology PPE research group (Prof. Dr. Ansgar Kahmen) under the supervision of Dr. Erika Hiltbrunner.

> to image tetrazolium-stained shoots of both grasses

Maxim Faroux's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Kiel University in the year 2021

Title: The aquaporin PIP2;1 as a potential interaction partner of PSKR1

The aquaporin PIP2;1 exists in close proximity to PSKR1 in the plasma membrane and might be a kinase substrate of PSKR1

The peptide hormone phytosulfokine (PSK) is perceived by the membrane-bound LRR-receptor kinases PSKR1 and PSKR2 in Arabidopsis thaliana. Plants lacking both receptors are smaller. Three types of Förster resonance energy transfer (FRET) analyses were established to study proximity between PSKR1 and PIP2;1: FRET sensitized emission (FRET SE), using both confocal laser scanning microscopy and a plate reader, and FRET acceptor photobleaching (FRET AB). Data from FRET AB indicated spatial proximity between PIP2;1 and PSKR1 and phosphorylation of PIP2;1 by the kinase domain of PSKR1 was shown in vitro. Phosphosite mapping and functional analysis of the PIP2;1 phosphosites will provide insight into PIP2;1 regulation by PSKR1.

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Maxim Faroux conducted this work at the botanical institute in the group of Prof. Dr. Margret Sauter.

On application the DBG supports the meetings of early career scientists and researchers to further their scientific exchange of expertise. The society especially fosters the building of interdisciplinary and trans-sectional networks among emerging scientists.

The DBG invites applications from young scientists to be funded for the organization of the Eduard Strasburger-Workshop for early career scientists. A small group of graduates can apply for the funding under the auspices of a senior scientist from a scientific institution. The workshop is supposed to last about two days (including a networking evening) and shall address 25 to 40 participants. The DBG offers to support such an event with up to 5.000 Euros. 

Wissenschaftliche Themen und Zielsetzung

• Fachlich oder methodisch ausgerichtete Tagung aus den Pflanzenwissenschaften
• Sektions-/fachgebietsübergreifende Themen sind besonders erwünscht
• Plattform für Wissenstransfer und Ergebnisdiskussion
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David Clara's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Innsbruck University in the year 2021

Title: "Do natural seed bacterial microbiota play a role in soybean germination?"

In contrast to previous studies, we isolated naturally occurring bacterial seed endophytes and investigated their role during germination.

Seeds are known to interact dynamically with their associated microorganisms (i.e., the seed microbiota), which include endophytes (i.e., microorganisms spending at least part of their lifetime in inner seed structures). How they contribute to germination is unclear. We isolated a high number of bacterial colonies from soybean cotyledons and embryonic axes of different cultivars during germination, which were then characterised molecularly. Furthermore, we modified the seed microbiota and analysed the effects on seed germination. The molecular characterisation revealed a high bacterial endophyte diversity and differences between seed compartments and cultivars. A reduction of the microbial load had no effect on seed germination under sterile suboptimal conditions. Selective modifications of the seed microbiota led partly to germination promotion under a selected suboptimal condition, indicating the potential of a certain fraction of the microbiota. A detailed understanding of the dynamics between seeds and its microbiota during germination is crucial as the seed offers the possibility to design plant embryos that start life with an optimised microbiota.

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Read whole thesis at Innsbruck University: https://diglib.uibk.ac.at/ulbtirolhs/download/pdf/6554723?originalFilename=true

David Clara conducted this work at the Department of Botany in the research group of Univ.-Prof. Dr. Ilse Kranner under supervision of assoz. Prof. Thomas Roach and Dr. Davide Gerna.

Madita Sophie Knieper's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2021

Title: The role of cyclophilin CYP20-3 in the redox regulatory network of chloroplasts

A redox-dependent modulation of the PPIase activity of cyclophilin CYP20-3, an important regulatory hub in the redox network of chloroplasts, by the oxylipin 12-oxophytodienoic acid was determined, implying a tight coupling of different stresses (e.g. wounding) and defense mechanisms such as enhanced thiol synthesis.

The chloroplast is a metabolically active compartment of plant cells and, in addition, acts as sensor and transducer of environmental cues, e.g. by coordinating redox and diverse hormonal signaling pathways. The cyclophilin CYP20-3 is localized in the chloroplast stroma and displays at least four functions as target of thiol redox regulation, binding partner of 2-cysteine peroxiredoxin, receptor of oxylipins and regulator of the cysteine synthase complex. Thereby, CYP20-3 plays a major role in plant responses to oxidative stress.

The α-β-unsaturated cyclic ketone 12-oxophytodienoic acid (12-OPDA) is synthesized by a short enzyme cascade in the chloroplast, combining 13-lipoxygenases, allene oxide synthase and allene oxide cyclase starting with α-linolenic acid as substrate. 12-OPDA synthesis is strongly stimulated in high light, upon wounding and various stresses. 12-OPDA is independent regulator and in addition precursor of jasmonic acid.

To deeper explore the regulatory role of 12-OPDA on the CYP20-3 activity, 12-OPDA was synthesized with recombinantly produced enzymes and purified via rp-HPLC. CYP20-3 wild type protein and two cysteineàserine variants were incubated with 12-OPDA, and the peptidyl prolyl cis/trans isomerase activity measured photometrically. Surprisingly, the incubation with 12-OPDA had an ambivalent effect on the catalytic activity of CYP20-3. 12-OPDA inhibited reduced CYP20-3 but activated oxidized protein. This pattern was observed for wild type CYP20-3 and its cysteineàserine variant (C129S), whereas the activity of the variant C176S was unaffected by 12-ODPA. It is concluded that the cysteinyl residue 176 is essential for binding 12-OPDA to CYP20-3.

These and additional results from the thesis deepen our understanding of the crosstalk between 12-OPDA and thiol redox regulation using the example CYP20-3. CYP20-3 is a node of signal integration under diverse stress conditions.

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Madita Sophie Knieper conducted this work at the faculty of biology of Bielefeld University in the research group of Prof. Dr. Karl-Josef Dietz.

Lea-Franziska Reekers's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Westfälische Wilhelms-University Münster in the year 2021.

Title: A detailed localization analysis of the enzymes involved in Lewis a-epitope formation in Arabidopsis thaliana

The study shows a way to visualize the full-length version of Arabidopsis Galactosyl­transferase 1 (GalT1) for the first time, which – besides studying its own localization – also allowed to investigate a possible interaction with the follow-up enzyme Fucosy­transferase c (FucTc).

N-glycans are attached co-translationally to nascent glycoproteins in the ER lumen (Abeijon & Hirsch­berg, 1992; Helenius & Aebi, 2002), and become further modified during travelling through the Golgi apparatus (Faye et al., 1989). The last modifications in plant cells are synthesized by the membrane-anchored enzymes GalT1 and FucTc, which results in complex-type N-glycans with terminal Lewis-a epitopes (Fitchette-Laine et al., 1997; Leonard et al., 2002). These epitopes on plant secretory glycoproteins were immunologically detected only at the TGN and the plasma membrane/cell wall. However, Arabidopsis FucTc localized as C-terminal reporter fusion not only in the Golgi apparatus, but preferentially at the perinuclear ER (Rips et al., 2017).

In my thesis I have investigated a possible cause for this phenomenon by analyzing multiple reporter fusions via CLSM microscopy upon transient expression in proto­plasts. The protoplasts were either prepared from A. thaliana wildtype or knock-out mutants that I had obtained by the CRISPR/Cas9 system for the FUCTc and GALT1 genes. Thereby I could show that GalT1 (Strasser et al. 2007), which could not be visualized as full-length version so far, is a factor involved in releasing FucTc from the perinuclear ER to the Golgi. Moreover, also FucTc seems to influence the localization of GalT1, which further supports an interaction of the two enzymes in the secretory system. My work has therefore contributed to solving a puzzle in plant cell biology.  

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Lea-Franziska Reekers conducted this work at the Institute of Plant Biology & Biotechnology (IBBP, WWU Münster) in the group of Prof. Dr. Antje von Schaewen.

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Referenzen

Abeijon, C., & Hirschberg, C. B. (1992). Topography of glycosylation reactions in the endoplasmic reticulum. Trends in Biochemical Sciences, 17(1), 32–36. doi.org/10.1016/0968-0004(92)90424-8

Faye, L., Johnson, K. D., Sturm, A., & Chrispeels, M. J. (1989). Structure, biosynthesis, and function of asparagine‐linked glycans on plant glycoproteins. Physiologia Plantarum, 75(2), 309–314. doi.org/10.1111/j.1399-3054.1989.tb06187.x

Fitchette-Laine, A.-C., Gomord, V., Cabanes, M., Michalski, J.-C., Saint Macary, M., Foucher, B., Cavelier, B., Hawes, C., Lerouge, P., & Faye, L. (1997). N-glycans harboring the Lewis a epitope are expressed at the surface of plant cells. The Plant Journal, 12(6), 1411–1417. doi.org/10.1046/j.1365-313x.1997.12061411.x

Helenius, J., & Aebi, M. (2002). Transmembrane movement of dolichol linked carbohydrates during N-glycoprotein biosynthesis in the endoplasmic reticulum. Seminars in Cell and Developmental Biology, 13(3), 171–178. doi.org/10.1016/S1084-9521(02)00045-9

Leonard, R., Costa, G., Darrambide, E., Lhernould, S., Fleurat-Lessard, P., Carlue, M., Gomord, V., Faye, L., & Maftah, A. (2002). The presence of Lewis a epitopes in Arabidopsis thaliana glycoconjugates depends on an active  4-fucosyltransferase gene. Glycobiology, 12(5), 299–306. doi.org/10.1093/glycob/12.5.299

Rips, S., Frank, M., Elting, A., Offenborn, J. N., & von Schaewen, A. (2017). Golgi α1,4-fucosyltransferase of Arabidopsis thaliana partially localizes at the nuclear envelope. Traffic, 18(10), 646–657. doi.org/10.1111/tra.12506

Strasser, R., Bondili, J. S., Vavra, U., Schoberer, J., Svoboda, B., Glössl, J., Léonard, R., Stadlmann, J., Altmann, F., Steinkellner, H., & Mach, L. (2007). A unique β1,3-galactosyltransferase is indispensable for the biosynthesis of N-glycans containing Lewis a structures in Arabidopsis thaliana. Plant Cell, 19(7), 2278–2292. doi.org/10.1105/tpc.107.052985

Michelle Schlösser's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bonn University in the year 2021

Title: Characterization of the ER-localized glutaredoxins GRXC3 and GRXC4 in Arabidopsis

Arabidopsis thaliana GRXC3 and GRXC4 are type II membrane proteins in the ER lumen with high in vitro oxidative activity towards roGFP2 as a substrate, which suggests that the two oxidoreductases are involved in oxidation of protein thiols in the ER.

Class I glutaredoxins (GRXs) are small oxidoreductases that use reduced glutathione (GSH) as a co-factor to reduce or oxidize substrate proteins. The Arabidopsis genome encodes six class I GRXs of which GRXC3 and GRXC4 are generally assumed to be secreted. Some algorithms for prediction of transmembrane proteins, however, predict both proteins as single-spanning membrane proteins with an N-terminal transmembrane domain (TMD) albeit with different orientations in the membrane as either type I or type II proteins. While such a membrane anchor could prevent the proteins from being secreted further functional analysis then requires also knowledge about the protein orientation relative to the respective membrane. Fusion of GRXC3 and GRXC4 with redox-sensitive GFP2 (roGFP2) at their N- and C-termini and expression in tobacco indicates both proteins as type II ER membrane proteins with their catalytic domains oriented towards the lumen. Additional studies with only the TMDs fused to roGFP2 showed that the TMDs alone are sufficient to keep roGFP2 in the ER and thus are likely to act as membrane anchors that simultaneously restrict the localization of both proteins to the ER.

To further study the function of GRXC3 and GRXC4, both proteins were synthesized as recombinant proteins and purified. Like their cytosolic siblings, both proteins are capable of reversibly reducing and oxidizing roGFP2 as an artificial substrate protein. Surprisingly, however, in comparison to cytosolic GRXC1 the catalytic properties of GRXC3 and GRXC4 appear to be shifted towards the oxidizing reactions in which addition of glutathione disulfide leads to oxidation of roGFP2.

Taken together, these studies show a revised localization of GRXC3 and GRXC4 with the catalytic functions being likely involved in oxidative protein folding in the ER. The results of this Master thesis thus set the base for further functional analysis of these proteins.

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Michelle Schlösser conducted this work at the Institute of Crop Science and Resource Conservation (INRES) under supervision of Dr. José Ugalde and Prof. Dr. Andreas Meyer.

Dorothea Vesely's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Leipzig University in the year 2021.

Title: Investigation of terpene biosynthesis in cyanobacteria

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Dorothea Vesely conducted her work at Leipzig University's Institute of Biology under the supervision of Dr. Raimund Nagel in the group of Prof. Severin Sasso.

The Wilhelm Pfeffer Prize is awarded by the DBG's Wilhelm Pfeffer Foundation for an outstanding PhD thesis (dissertation) in the field of plant sciences and scientific botany. It is considered to promote young scientists.

The Prize comprises

• a document comprising the name of the award winner, the title of the award winning thesis togehter with its date and place of publication. The document is underwritten by the president of the Wilhelm Pfeffer board
• a sum of € 2500.-
• a travel allowance for the award winner to join the "Botanik-Tagung" (International Conference of our German Society for Plant Sciences) where the prize will be presented.

The Wilhelm Pfeffer Prize cannot be allocated to more than a single person.

Proposing candidates

Proposals can be made by full members or honorary members of the German Botanical Society only. No one can propose his/her own PhD thesis.

Proposals should comprise a written outline why the thesis is of special value, a Curriculum Vitae, and a publication list of the proposed candidate, if available.

The candidates should have received their PhD from a scientific university. The candidates may not exceede 30 years of age when finished their PhD. Times of military or civil services and parenting times may be excluded. The thesis should be younger than three years upon proposal.

The award winner is obliged to present his/her thesis in an oral presentation of about 30 minutes after the presentation of the prize. The oral presentation will be integrated into the programme of the annual conference of the German Botanical Society (Botanik-Tagung). The manuscript of the oral presentation will be submitted to the editors of Plant Biology.

Survey and deadline

More information about the procedures are in the constitution of the Wilhelm Pfeffer Foundation (published in Plant Biology 7 (2005), # 6, pages N15-N17).

The person named in the announcement has to receive complete proposals in an electronic version until the date cited in the announcement.

In the year 2022 DBG's representatives at the Universities evaluated master theses in the plant sciences. The following persons received the award for best master theses (in alphabetical order):

Aylin Durmaz (Paris Lodron Universität Salzburg)
Artificially evolved nickel resistance in Pseudomonas syringae infecting the heavy metal hyperaccumulator Noccea caerulescens

Tora Fougner-Okland (Ludwig-Maximilians-Universität München)
Exploring antibacterial gene silencing approaches in Xylella fastidiosa and Xanthomonas campestris

Josephine Franke (Universität Rostock)
Taxonomic analyses of clonal cultures belonging to the genus Pantocsekiella based on sequence analyses of various genetic markers

Marlene Handl (Ruprecht-Karls-Universität Heidelberg)
From ER to tonoplast: Targeting of VHA-a subunits and visualization of ERtonoplast membrane contact sites

Valtentin Heimer (Universität Innsbruck)
Polyploidisation was not involved in the origin of five endemic species from southern Europe but is otherwise frequent in Euphorbia sect. Esula (Euphorbiaceae)

Aylin Kerim (Universität Bonn)
Physiological and Molecular Characterization of Glyoxalase I in the Glyoxalase System among Arabidopsis thaliana Ecotypes

Lea Klepka (Philipps-Universität Marburg)
Rapid adaptation of the plant species Galium wirtgenii to novel conditions in restored meadows

Lisa Koch (Friedrich-Alexander-Universität Erlangen-Nürnberg)
Influence of elevated temperature in combination with different nitrogen concentrations on the growth and development of potato plants

Lena Knorr (Westfälische Wilhelms-Universität Münster)
The importance of intracellular NAD dynamics in the pattern-triggered immune response of plants

Elina J. Negwer (Christian-Albrechts-Universität zu Kiel)
Induction of UV-screening compounds by N-deficiency in Helianthus annuus

Lukas Schulz (Technische Universität München)
Biochemical and Biophysical Characterization of PIN-FORMED8 Protein from Arabidopsis thaliana

Magdalena Slawinska (Ruprecht-Karls-Universität Heidelberg)
Exploring the impact of stomatal morphology on gas exchange

Anna Sophie Stasche (Universität Bielefeld)
Transcriptional control of photosynthetic gene expression in Arabidopsis thaliana

Vera Wagner (Martin-Luther-Universität Halle-Wittenberg)
Regulatory lipids at the membrane-actin interface in polar growing plant cells

Malte L. Weber (Carl von Ossietzky-Universität Oldenburg)
Biodiversity of soil fauna associated with arboreal soil in tree cavities. A biogeographical approach

Malte L. Weber's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Carl von Ossietzky-Universität Oldenburg in the year 2022 with the title:

Detritus-filled crotches – an overlooked tree-related microhabitat in Central Europe

The theses systematically describes the fauna associated with crown microsoils in tree crotches in central Europe for the first time.

In the field of biodiversity research, tree-related microhabitats in the temperate zone have received substantial interest in the last decade, but one particular microhabitat type, crown microsoils in tree crotches, has largely escaped the attention of scientists. We present a study from Central Europe that focused on the meso- and macrofauna in this microhabitat type. In twelve crotches we found more than 3000 individual animals out of 14 orders, encompassing all major elements of the terrestrial soil decomposer food web. Collembola accounted for more than 50 % of the total. As expected, taxon richness correlated with habitat size. We conclude that this is an ideal natural system to study fundamental ecological questions of faunal community assembly.

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Malte L. Weber conducted this work at the Institute for Biology and Environmental Sciences in the Functional Ecology of Plants lab with Prof. Dr. Gerhard Zotz.

Samuel Nestor Meckoni's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at TU Braunschweig in the year 2024 with the title:

Establishing transformation methods in Utricularia gibba to investigate its potential as a biotechnological production system by examining trap specific secretion mechanisms

The unique suction traps of the carnivorous Utricularia plants could be put to biotechnological use by converting them into product accumulation sites.

The exact metabolic and transport processes of the fascinating traps of the carnivorous plants of the genus Utricularia are not yet known in detail, which is an obstacle to their possible biotechnological use. In order to investigate these transport processes in more detail, the plants were genetically modified. An Agrobacterium-mediated gene transfer method was utilized.

My research focused on the potential of Utricularia gibba as a biotechnological production system by investigating the secretion of foreign proteins by its glandular cells using a known promoter. Bioinformatic tools were used to identify signal peptides that could facilitate protein accumulation in the plant's traps. The results showed promising candidates for further investigation, and the integration of these genes into the plant will provide valuable insights into their function and potential applications.

In addition, it was observed that the traps of the plant become reddish when experiencing nitrogen deficiency stress. This could help to unravel a novel promoter that could be used as a switch to regulate production.

Future research is planned for my doctoral studies. Thereby, the genetic modification methods will be optimised to conduct a proof-of-concept experiment regarding protein secretion and to extend the investigations to the secretion of small molecules.

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Samuel Nestor Meckoni conducted this work at the at the Institute of Plant Biology in the working group of Professor Dr. Boas Pucker.

Lukas Schulz's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Technische Universität München in the year 2022

Title: "Biochemical and Biophysical Characterization of PIN-FORMED8 Protein from Arabidopsis thaliana"

Schulz established a new electro-physical method to characterize transport proteins, characterized the biochemical and biophysical properties of a PIN-FORMED (PIN) Auxin exporter thoroughly and parts of his work were published in a Nature article (DOI: 10.1038/s41586-022-04883-y). 

The phytohormone auxin controls essentially all aspects of plant growth and development. The most abundant auxin is Indole-3-acetic acid (IAA). It is distributed through the plant by long distance transport in the phloem and by polar auxin transport (PAT) from cell to cell. IAA is a weak acid and can therefore enter the cell by passive diffusion at a pH of 5. Once in the cell, at neutral pH, the IAA molecules dissociate and auxin efflux carriers are mandatory for export out of the cell. The PIN-FORMED (PIN) efflux carriers are the key players in PAT. In Arabidopsis thaliana, there are eight different PIN proteins divided into three subgroups, the canonical plasma membrane- localized PINs, the noncanonical ER-localized PINs and the intermediate PIN6. Recently, the structure of the non-canonical PIN8 was described in the publication "Structures and mechanism of the plant PIN-FORMED auxin transporter", revealing that PINs form dimers and operate by an elevator-mechanism. I contributed the biochemical and biophysical characterization of PIN8 by solid supported membrane (SSM)-based electrophysiology, which were a part of this thesis to the publication.
To better understand the SSM-electrophysiology measurements, a theoretical model of the proteoliposomes and a mathematical derivation of the electrogenic transport was proposed. Additionally, to further optimize the assay, the sensor preparation process was critically re-evaluated and optimized. A focus of this thesis was also to distinguish between binding and transport current response of the PIN8 substrates IAA and N-1- naphthylphthalamic acid (NPA) in SSM electrophysiology. The results show that the inhibitor NPA induces a binding current, whereas IAA induces a mix of transport- and a binding current. Additionally, binding, transport and inhibition constants were investigated and a rather low apparent affinity for IAA was determined. In order to understand the transport mechanism of PIN8 better, transport properties of PIN8 mutants were determined. The results were additionally confirmed in a Xenopus laevis oocyte-based efflux assay, showing a high degree of correlation between both assays. With the help of the PIN8 mutants and a substrate screening, the substrate specificity of PIN8 was investigated, leading to insights of the properties required to interact with the PIN8 binding pocket.

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Lukas Schulz conducted this work at the Chair of Plant Systems Biology in the working group of PD Dr. Ulrich Z. Hammes.

Josephine Franke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Rostock in the year 2022

Title: Taxonomic analyses of clonal cultures belonging to the genus Pantocsekiella based on sequence analyses of various genetic markers

The thesis made a significant contribution to the taxonomy of an important diatom genus by using a variety barcoding markers, some of which have not been used previously. The chosen Pantocsekiella is an important bioindicator for water quality assessments, but its morphology made this challenging due to its highly variable morphology. 

Diatoms are excellent bioindicators of current or past conditions of a water body. Species identification is done using morphological characteristics of the detailed cell walls and can be complemented by molecular methods. In this work, in addition to some barcoding markers already established for diatoms, further DNA regions were tested for their suitability within the genus under consideration. Using these molecular data, an attempt was made to resolve ambiguities within the genus Pantocsekiella K.T. KISS & ÁCS. It contains several species with variable characters, which may make identification difficult. The sequences of clonal cultures for five DNA regions (chloroplastid, mitochondrial, and nuclear) were amplified using PCR and then sequenced. The sequences thus obtained were evaluated with the result that some taxa were not molecularly distinct (P. ocellata (PANTOCSEK) K.T. KISS & E. ÁCS, P. kuetzingiana (THWAITES) K.T. KISS & E. ÁCS, and P. polymorpha (B. MEYER & HAKANSSON) K.T. KISS & E. ÁCS). Others showed molecular variability but could not be clearly separated into groups corresponding to taxa previously assigned based on morphological characters (P. comensis (GRUNOW) K.T. KISS & E. ÁCS, P. pseudocomensis (SCHEFFLER) K.T. KISS & E. ÁCS, P. costei (DRUART & STRAUB) K.T. KISS & E. ÁCS, P. delicatula (HUSTEDT) K.T. KISS & E. ÁCS, P. hinziae (HOUK, KÖNIG & KLEE) K.T. KISS & E. ÁCS). Whether it is one species with intraspecific morphological as well as molecular variability or several species, which do not correspond to the previous classifications cannot be clarified unambiguously and conclusively on the basis of the data obtained here. This can be the starting point for further investigations. The newly considered barcoding markers could be easily applied to the genus and should be tested in further taxa. Separation and correct description of diatom species is relevant in that even very similar species can show different tolerances and responses to environmental parameters, increasing the potential for meaningful application as bioindicators.

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Josephine Franke conducted this work at the Institute / Chair of General and Special Botany in the working group of Dr. Thomas Hübener.

Aylin Kerim's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bonn University in the year 2022

Title: "Physiological and Molecular Characterization of Glyoxalase I in the Glyoxalase System among Arabidopsis thaliana Ecotypes"

For the first time this work showes that ecotypes of Arabidopsis thaliana have specific molecular adaptations of the glyoxalase system, such as lower toxicity to the toxic reactive carbonyl species 2-keto-D-glucose due to high expression of the gene encoding the scavenging enzyme glyoxalase I;2.

Reactive carbonyl species (RCS) are toxic compounds produced mostly during sugar metabolism and are detoxified mainly by the glyoxalase system. In my master's thesis, I investigated the growth characteristics of 20 ecotypes of Arabidopsis thaliana exposed to the RCS methylglyoxal and 2-keto-D-glucose (KDG). In these plants, I also performed transcriptional analysis of all homologs of glyoxalase I by quantitative RT-PCR. Two ecotypes that occur in the same habitat exhibited particularly strong root growth when plants are grown in the presence of KDG, while root growth of other ecotypes was either unaffected or reduced by KDG compared to the Columbia ecotype. I found that the gene encoding the isoform of glyoxalase I;2 (GLXI;2) is highly expressed in one of these ecotypes, suggesting that higher expression of GLXI;2 is involved in the increased KDG detoxification capacity of these ecotypes during seedling establishment. These data pave the way for further research to analyze the molecular adaptations of the RCS-scavenging glyoxalase system in different ecotypes.

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Aylin Kerim conducted this work in the department of Molecular Plant Physiology, IZMB in the working group of Prof. Dr. Veronica G. Maurino.

Tora Hedvig Fougner-Økland's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ludwig-Maximilians-Universität München in the year 2022

Title: Exploring antibacterial gene silencing approaches in Xylella fastidiosa and Xanthomonas campestris

For the first time, RNA-based treatments have been tested against the devastating agricultural pest Xylella fastidiosa

RNA-based treatments are a promising crop protection strategy against eukaryotic pests, but similar approaches against bacterial crop pests remain largely unexplored. The study tested approaches to achieve Antibacterial Gene Silencing (AGS) in two important bacterial plant pathogens, Xylella fastidiosa fastidiosa and Xanthomonas campestris pv. raphani. Therfore Fougner-Økland synthesized different RNAs and tested their effect by targeting bacterial growth and virulence. Fougner-Økland did not find evidence that RNA treatments reduced bacterial colonisation in Arabidopsis thaliana, but some results suggest that RNAs targeting a gene for chitin metabolism could change growth dynamics and phenotype in chitin-dependent growth conditions. This work opens possibilities for new measures against bacterial crop pathogens, which are notoriously difficult to control. Future efforts may focus on more sensitive detection methods for AGS events.

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Tora Hedvig Fougner-Økland conducted this work at the the LMU Chair of Genetics in the working group of Prof. Dr. Silke Robatzek.

Lena Knorr's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Westfälische Wilhelms-Universität Münster in the year 2022

Title: The importance of intracellular NAD dynamics in the pattern-triggered immune (PTI) response of plants

Knorr provides insights into PTI-mediated physiological dynamics in the cytosol of plants and gives supporting evidence for the importance of NAD metabolism in plant immunity.

At pathogen attack, the plant cell recognizes conserved pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs) leading to the activation of pattern-triggered immunity (PTI), the first line of immunity in plants. Several key mechanisms involved, such as calcium channel regulation, phosphorylation of signalling proteins or the generation of the apoplastic ROS burst, have received extensive attention. These events and the downstream defences they initiate are reliant on a profound re-routing of cellular metabolism. While it is evident that metabolic dynamics are at the heart of the network of pathogen response strategies the specific integration of primary metabolism and pathogen defence programs is poorly understood.

Recently, the metabolic cofactor nicotinamide adenine dinucleotide (NAD) has gained attention as part of the effector-triggered immune response (ETI), which includes the degradation by cellular NAD by TIR-associated NADase activity. Independently, defects in pathogen responses have been observed in mutants affected in NAD metabolism.

The study focuses on the serendipitous observation of an early NAD redox signature in Arabidopsis leaves triggered by the bacterial elicitor flg22. Since the transient is rapid, and difficult to resolve through destructive approaches for NADH/NAD⁺ quantification, I established a monitoring system for NADH/NAD⁺ in vivo exploiting the genetically-encoded fluorescent biosensor Peredox-mCherry. This approach has been the basis for testing specific hypotheses as to (i) the characteristics of the NAD redox transient, (ii) its origin and (iii) its potential significance in establishing immunity, by using genetic and chemical interference.

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Lena Sophie Knorr conducted this work at at the Institute of Plant Biology and Biotechnology (IBBP,WWU Münster) in the group of Prof. Markus Schwarzländer.

Vera Wagner's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Martin-Luther-Universität Halle-Wittenberg in the year 2022

Title: Regulatory lipids at the membrane-actin interface in polar growing plant cells

The results of this work indicate for the first time that class VIII myosins mediate actin attachment to plasma membrane phosphoinositides, with phosphatidylinositol-(4,5)-P₂ nanodomains playing a particularly important role.

The polar tip growth of pollen tubes requires the coordination of membrane-associated processes for focused secretion and recycling of membrane vesicles with the dynamics of the cytoskeleton. Using a combination of in vitro characterization of recombinant proteins and live cell confocal microscopy, the role of previously little studied plant-specific class VIII myosins at the actin-membrane interface of pollen tubes was investigated. The main results are based on in vitro lipid overlay tests and liposome sedimentation tests, on the modification of the target proteins as well as quantitative image analysis of transiently expressed fluorescence fusions.

Class VIII myosins are characterized by high-affinity binding to actin and low motor activity. However, their physiological function is not well understood so far. In Arabidopsis thaliana are four members of class VIII myosins, two of which are specifically expressed in pollen. The analyses presented here show that the pollen-specific representatives ATM2 and VIII-B can bind to anionic membrane lipids and this binding is mediated by a C-terminal polybasic sequence region, which representatives of the other plant myosin class XI lack. Fluorescently labeled ATM2 fusions localize in pollen tubes to the subapical plasma membrane and to filamentous structures of the cell periphery, which colocalize with cortical actin. This distribution pattern supports a function of ATM2 at the actin-membrane interface. Deletion of the lipid-binding C-terminal region or alternative coexpression of the phosphoinositide phosphatase SAC9 both decrease plasma membrane association of ATM2, indicating that binding of ATM2 to anionic lipids is necessary for its membrane association. The reduced membrane association of ATM2 further reduces a stabilizing effect of ATM2 on actin dynamics observed here for the first time. The presented results advance the understanding of the dynamic regulation of the actin cytoskeleton by membrane lipids and define class VIII myosins as elements of the actin-membrane interaction. The membrane association of class VIII myosins through binding to anionic lipids creates an interaction point between actin filaments and lipid nanodomains of the plasma membrane. The resulting local stabilization of the membrane contact presumably subsequently facilitates the interaction with other regulatory proteins for the coordination of the apical secretion.

Parts of the work are pulished in the paper: The pollen-specific class VIII-myosin ATM2 from Arabidopsis thaliana associates with the plasma membrane through a polybasic region binding anionic phospholipids. DOI: https://doi.org/10.1016/j.biochi.2022.10.002

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Vera Wagner conducted this work at the Institute of Biochemistry and Biotechnology in the working group of Prof. Dr. Ingo Heilmann.

-> to a model of the possible function of ATM2 at the membrane-actin interface

Aylin Durmaz's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Paris Lodron Universität Salzburg in the year 2022

Title: Artificially evolved nickel resistance in Pseudomonas syringae infecting the heavy metal hyperaccumulator Noccea caerulescens

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Achtung: Bitte Bilder mit sich selbst verlinken, damit vergrößerbar!!

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Aylin Durmaz conducted this work at the Institute xx in the working group of Assoz.-Prof. Dr. Anja Hörger

Lisa Koch's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) in the year 2022

Title: Influence of elevated temperature in combination with different nitrogen concentrations on the growth and development of potato plants

Overexpression of the tuberigen StSP6A in combination with high nitrogen feeding regimes is able to overcome the inhibiting properties of high nitrogen treatment and heat on the tuberization process and therefore increase yield under otherwise inhibiting conditions.

The combinatory effects of elevated temperature and nitrogenous fertilizer on the development and yield of potato plants (Solanum tuberosum L.) have not been described yet. Research on this topic is of great importance as climate change and a growing world population result in an endangered food stability. Potato belongs to the most important staple crops worldwide. Potato plants are susceptible to elevated ambient temperature resulting in a reduced yield.

Nitrogen (N) is an essential factor for plant growth and development and large amounts of nitrogenous fertilizers are applied in agriculture to enhance yield of various plants. There are many efforts to increase nitrogen use efficiency in order to reduce the negative impact on the environment by massive usage of fertilizers. In addition, growth of potato plants is favored by nitrogen; however, tuberization is inhibited by high N fertilization.

In this thesis, the effects of deficient/ excess N in combination with heat on potato plant growth and tuber development were investigated. Low N resulted in small plants with an early onset of tuberization and leaf senescence. These processes were either delayed or enhanced by heat, respectively. Both plant and tuber development were hampered by low N as compared to plants grown with medium (optimal) N supply.

High N resulted in big bushy plants while tuberization was strongly delayed which resulted in a shift in the source-sink-balance towards green biomass at the expense of tuber yield. Yield was highest in plants grown with medium N concentration under control conditions. However, these plants exhibited the strongest heat mediated yield reduction.

Under elevated temperature the yield did not significantly differ between different N regimes. This showed that N fertilization might have no positive effect on yield under heat, which is problematic from a climate change point of view.

The inhibition of tuberization through high N was overcome in transgenic plants that overexpressed StSP6A, a key tuberization gene, under control of the StLS1 promoter (active in green tissues). Instead of decreased yield under high N availability, the transgenicity resulted in even higher yield than under medium N supply. This was also true under elevated temperatures, where highly fertilized plants performed best. This suggests that a combination of StSP6A overexpression and high N seems to be a good possibility to ensure a stable potato yield under elevated temperature.

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Lisa Koch conducted this work at the Department of Biochemistry in the group of PD Dr. Sophia Sonnewald.

Marlene Handl's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ruprecht-Karls-Universität Heidelberg in the year 2022

Title: From ER to tonoplast: Targeting of VHA-a subunits and visualization of ERtonoplast membrane contact sites

While the V-ATPase is one of the most abundant tonoplast protein complexes it remained to be investigated how its VHA-a subunit dependent sorting is facilitated correctly within the endomembrane system. Within this thesis we identified a PLL amino acid sequence motif that seems to be required for the correct targeting of A. thaliana VHA-a3 and M. polymorpha VHA‑a to the tonoplast.

The vacuole is a multifunctional organelle that occupies up to 90 % of the volume in a plant cell. Most vacuolar functions require a proton gradient which is maintained by the concerted action of Vacuolar-type H⁺-ATPases (V-ATPase) and H⁺-Pyrophosphatases (V-PPase). Targeting of V-ATPase complexes is dependent on the VHA-a isoform incorporated into the membrane integral V₀ subcomplex. In A. thaliana, VHA-a2 and VHA-a3 confer tonoplast localization while VHA-a1 targets the proton pump to the trans-Golgi Network/Early Endosome (TGN/EE) (Dettmer et al., 2006). Recently, a seed plant specific a1-targeting domain (a1-TD) was identified in VHA-a1 that is necessary and sufficient for targeting to the TGN/EE (Lupanga et al., 2020). VHA-a3 is thought to be trafficked to the tonoplast via the COPII-independent provacuolar route (Viotti et al., 2013; Lupanga et al., 2020). As the a1-TD is not conserved in VHA-a3, it remains to be determined if this isoform possesses a sorting signal that targets the membrane protein to the tonoplast. In this thesis, we employed multiple sequence alignments, site-directed mutagenesis, and live imaging to identify a PLL motif that is required for tonoplast sorting of VHA-a3 as well as of the ancestral VHA-a isoform of M. polymorpha. MpVHA-a and VHA-a3 harboring mutations in this motif are mislocalized to the TGN/EE. We further propose that loss of this PLL motif in VHA-a1 was the first step towards the development of a dedicated TGN/EE VHA-a isoform in seed plants.

_{Dettmer, J., Hong-Hermesdorf, A., Stierhof, Y.D., and Schumacher, K. (2006). Vacuolar H+-ATPase activity is required for endocytic and secretory trafficking in Arabidopsis. Plant Cell 18: 715–730.
Lupanga, U., Röhrich, R., Askani, J., Hilmer, S., Kiefer, C., Krebs, M., Kanazawa, T., Ueda, T., and Schumacher, K. (2020). The Arabidopsis V-ATPase is localized to the TGN/EE via a seed plant-specific motif. Elife 9: 1–40.
Viotti, C. et al. (2013). The Endoplasmic Reticulum Is the Main Membrane Source for Biogenesis of the Lytic Vacuole in Arabidopsis. Plant Cell 25: 3434–3449.}

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Marlene Handl conducted this work at the Department of Cell Biology at the Centre for Organismal Studies (COS) Heidelberg in the group of Prof. Dr. Karin Schumacher under the supervision of Prof. Dr. Karin Schumacher and Dr. Upendo Lupanga.

Magdalena Slawinska's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ruprecht-Karls-Universität Heidelberg in the year 2022

Title: Exploring the impact of stomatal morphology on gas exchange

We adjusted the formula to calculate anatomical maximum stomatal conductance (g_smax , defined as the quantitative rate of how much water vapour or CO₂ goes through stomata [mol sec^-1 m^-2]) for grass stomatal morphology and proposed a cell-wall modifying role for the peroxidase BdPOX to restrict guard cell elongation and guarantee water-use efficient stomatal movements.

Stomata are epidermal breathing pores allowing plants to regulate carbon assimilation and water loss. In grasses, unique graminoid stomatal morphology has been shown to enable faster stomatal movements, larger pore apertures and improved water use efficiency in comparison with other stomatal morphologies. Here, we attempted to deepen our understanding of how guard cells’ length in grass stoma contributes to water-use efficient stomatal movements and improved stomatal performance, and identify the mechanism of action of BdPOX peroxidase in the elongation of guard cells. We (i) adjusted anatomical g_smax formula for graminoid morphology and compared anatomical g_smax estimation in wild-type B. distachyon (WT) and bdpox-1 mutant, (ii) performed high resolution confocal microscopy of wild-type B. distachyon and bdpox-1 stomata to provide foundations for building a mechanical model of B. distachyon stomata to understand if guard cells length affects stomatal movements, and (iii) analysed phenolic compounds autofluorescence and ROS levels in cell walls in guard cells of wild-type B. distachyon and bdpox-1 mutant to elucidate the mechanism of action of BdPOX peroxidase. We show physiological g_smax in B. distachyon can be reliably estimated by calculating the theoretical anatomical g_smax. Moreover, we present an optimized guard cells staining protocol allowing obtaining high-resolution confocal stacks suitable for mechanical modeling of grass stomata in different genotypes. Finally, we propose that BdPOX acts at the end of stomatal development in B. distachyon by depositing phenolic compounds, leading to restriction of guard cells elongation.

The adjusted formula to calculate g_smax for grass stomata was published (DOI: 10.1017/qpb.2021.19) and the findings on BdPOX’s role can be found as a preprint (DOI: 10.1101/2022.07.03.498611).

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Magdalena Slawinska conducted this work at the Centre for Organismal Studies (COS) in the working group of Dr. Michael Raissig

Anna Sophie Stasche's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Bielefeld in the year 2022

Title: Transcriptional control of photosynthetic gene expression in Arabidopsis thaliana

Stasche found out that the photosynthetic transcriptional regulation in Arabidopsis thaliana is modular. To know about this regulation is crucial for future biotechnological improvements of cropplant yields.

Starting with the hypothesis that “photosynthetic transcriptional regulation” is regulation of either the Calvin Benson Bassham cycle, the photosynthetic electron transport chain or possibly both, a meta analysis of publicly available data of known photosynthetic transcriptionfactors GOLDEN 2-LIKE 1(GLK1), GOLDEN 2-LIKE2 (GLK2), GATANITRATE-INDUCIBLECARBONMETABOLISM-INVOLVED (GNC), GNC-LIKE (GNL), ELONGATEDHYPOCOTYL 5 (HY5) and PYTOCHROMEINTERACTINGFACTORs (PIFs)1, 3, 4 and 5 was performed. In the meta analysis binding information in the form of ChIP – and DAP -seq experiments, as well as microarray and RNA-seq differential transcriptome data of overexpression and knock-out mutants was incorporated.

The meta analysis revealed several positive and negative instances of transcriptional regulation between the different analysed TFs, suggesting that the regulatory network upstream of photosynthetic genes is looped and net-like rather than the previously assumed hierarchical organisation. In accordance with existing literature the four PIF family TFs were found to be general suppressors of photosynthesis. While the remaining TFs act on different sets of photosynthetis genes with for example expression of genes encoding parts of the photosynthetic antenna likely being upregulated by GLKs and downregulated by GNC. In contrast expression of transcripts of photorespiration related genes is indicated to be suppressed by GLKs and increased by GNC. The photosynthetic genes can be devided into different modules based on the regulatory patterns seen in the metaanalysis.

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Anna Sophie Stasche conducted this work at the faculty of biology in the work group „computational biology“ of Prof. Dr. Andrea Bräutigam.

Lea Klepka's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Philipps-Universität Marburg in the year 2022

Title: Rapid adaptation of the plant species Galium wirtgenii to novel conditions in restored meadows

Early mowing of restored meadows leads to an advancement of flowering onset and lower early growth in Bedstraw within only a few years.

The success of ecosystem restoration might significantly depend on whether restored populations are able to adapt fast enough to novel conditions. However, underlying mechanisms and drivers of evolutionary change in response to land management practices remain to be uncovered. In this Master's thesis, rapid adaptation to early mowing in restored alluvial grassland meadows was investigated. For the restoration 20 years ago, hay transfer was applied. Therefore, plant material including seeds obtained by mowing remnant alluvial meadows was transferred to meadows that had to be restored. Offspring of the plant species Galium wirtgenii from both hay donor and recipient areas were grown in a common garden and mowing was simulated during the flowering period. Plants from restored meadows flowered earlier and grew less in early live stages in response to the early mowing. Regarding the regeneration capacity after the removal of the aboveground biomass during flowering, there were no differences between the plants of restored and ancient meadows. These results suggest that early flowering and low biomass in early growth stages are part of the adaptation strategy of G. wirtgenii, whereas an enhanced regeneration after mowing is not.
The Master's thesis shows that mowing early in the year acts as a strong selective agent on flowering phenology and early plant growth, which must be taken into consideration when managing restored habitats.

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Lea Klepka conducted this work at the Department of Biology in the working group of Prof. Lampei Bucharova.

Elina J. Negwer's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Christian-Albrechts-Universität zu Kiel in the year 2022

Title: Induction of UV-screening compounds by N-deficiency in Helianthus annuus

Major secondary compounds are no sink for carbon excess in nitrogen starved sunflowers: A reassessment of the Carbon-Nutrient Balance Hypothesis

In 1983, Bryant et al. published the controversial Carbon-Nutrient Balance Hypothesis (CNB) suggesting, inter alia, that the amount of carbon-based secondary compounds (CBSCs) in plants increases upon nitrogen deficiency in response to surplus photosynthetic carbon caused by reduced growth.

To add clarity to the debate whether the CNB is correct, carbon balances were used in this new approach to calculate the amount of carbon that was channeled into the biosynthesis of caffeoylquinic acids (CQAs) and lignin, each in comparison to the respective carbon gain of cell wall carbohydrates, or individual plant parts, to assess if CBSCs are a considerable carbon sink. The carbon assimilation of hydroponically grown, 13 days old sunflowers was measured via gas exchange and C/N-analysis, whereas the concentration of individual compounds was determined by chlorophyll fluorescence and HPLC (CQAs), as well as with the acetyl bromide assay (lignin and cell wall carbohydrates).

Although the concentration of the CQAs increased significantly in the leaves already within 24 h since transfer of the sunflowers into nitrogen deficient nutrient solution, the lignin concentration did not increase even at three days of nitrogen deficiency for any part of the plants (primary leaves, first secondary leaf pair, cotyledons, stem, or root). However, the induction period could not be extended, because at day three the photosynthesis rate started to decrease significantly due to nitrogen deficiency, which is not compatible with the assumptions of the CNB.

The net amount of carbon that was channeled into CQAs (<2%) or lignin (<7%) was much lower as compared to the portion gained by the cell wall carbohydrates (>60%). Interestingly, these amounts were not significantly influenced by the nitrogen status of the plants. However, the carbon allocation to different plant parts suggests that the carbon excess caused by reduced leaf expansion upon nitrogen deficiency was compensated by increased root growth.

Ultimately, the findings indicate that CQAs and lignin cannot function as a considerable sink for excess carbon caused by nitrogen deficiency, which is in conflict with the CNB. Bottom line, a single cause for the increased CQA concentration in nitrogen starved plants might be unlikely. Instead, previous findings allow for the conclusion that CQAs might serve multiple purposes in the context of nitrogen deficiency, such as antioxidative properties, modulation of growth and differentiation, herbivore defense and allelopathic effects.

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Elina J. Negwer conducted this work at the Botanical Institute in the Department of Ecophysiology in the working goup of Professor Wolfgang Bilger.

Valtentin Heimer's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Innsbruck in the year 2022

Title: Polyploidisation was not involved in the origin of five endemic species from southern Europe but is otherwise frequent in Euphorbia sect. Esula (Euphorbiaceae)

Heimer elucidated the genetic relationships of five endemic Euphorbia species that have almost not been studied so far. He showed that they are belonging to separate evolutionary groups despite their close geographic proximity.

A key factor for the diversification of flowering plants has been polyploidisation, which, however, appears of minor importance in the evolution of Euphorbia subgen. Esula. An exception is Euphorbia sect. Esula that includes roughly 100 species, many of which are widespread, but several have restricted distribution areas. We used ITS sequencing and relative genome size estimation to explore the evolutionary origin of E. gayi, E. graminifolia, E. tommasiniana, E. valliniana and E. variabilis, which are endemic to disjunct areas along the southern and western margins of the Alps as well as Corsica and Sardinia. In addition, we explored the incidence of polyploidy across different lineages of E. sect. Esula. Our phylogenetic results revealed several lineages with unresolved relationships that likely diverged in the late Miocene, but only one of them, the Eurasian Group, underwent considerable diversification, likely due to numerous polyploidisation events. Several polyploid or ploidy-mixed species from this group are distributed across large areas of Eurasia. All other lineages remained mostly diploid and species-poor, but dispersed to various continents, where most of the species have restricted distribution areas. All five endemic species are diploid but do not share a common ancestor. Both E. graminifolia and E. tommasiniana belong to the Eurasian Group whereas E. gayi, E. valliniana and E. variabilis belong to the Cosmopolitan Group and are thus not closely related to other European members of the section. Phylogenetic analyses recovered E. valliniana and E. variabilis as genetically distinct, although closely related. This, along with a clear morphological differentiation as revealed by morphometric analyses, supports their recognition as independent species. Our study highlights the important role polyploidisation had for plant diversification as well as the effects of other factors such as vicariance in disjunct refugia, which likely shaped the origin of the five endemic species from E. sect. Esula.

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Valtentin Heimer conducted this work at the Botany Institute in Innsbruck University in the working group of Prof. Dr. Peter Schönswetter. The work can be retrieved from: https://diglib.uibk.ac.at/ulbtirolhs/content/titleinfo/7738412?query=valentin%20Heimer 

Tobias Blank's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Leibniz Universität Hannover in the year 2023 with the title:

Analysis of secondary metabolites and their response to salinity in hairy roots of Lycium humile.

For the first time Tobias Blank analysed adaptive strategies of the extreme halophyte Lycium humile to saline environments on a metabolic level. He established hairy root cultures and exposed them to varying salinity, enabling detailed measurement of secondary metabolites in response to salt stress.

The increasing salinization of soils is a major global challenge, which requires innovative strategies for researching plant salt tolerance. This study focused on the largely unexplored halophyte species Lycium humile. This plant occurs naturally only in the high mountains and salt deserts of the Andes, South America. To investigate the mechanisms of salt tolerance of Lycium humile, we induced hairy root cultures using the bacterium Rhizobium rhizogenes. This technique enabled the growth of roots in a controlled environment and is ideally suited for studying plant responses to stress, especially given the strictly limited plant material. Three of these hairy root lines were then cultured in liquid media with varying concentrations of salt to simulate the challenging conditions these plants face in nature.

The experiment focused on analyzing the production of secondary metabolites in the roots, which could be crucial for the resilience of Lycium humile. The total amounts of phenolics, flavonoids, and alkaloids were measured. To gain a comprehensive understanding of these metabolic changes, Liquid Chromatography-Mass Spectrometry (LC-MS) was also employed. It was demonstrated that the total content of phenolics and flavonoids was increased in one of the hairy root lines under salt stress. Further significant shifts in secondary metabolites were revealed by the results of the LC-MS.

For the first time, this provided an insight into how the extremely halophilic Lycium humile chemically responds to salt. Whether the experiments with the hairy root cultures reflect the actual mechanisms of the whole plant and which compounds are involved in detail need to be determined in future experiments.

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Tobias Blank conducted the thesis at the Institute of Botany in Prof. Dr. Jutta Papenbrock's working group.

> photo of the working group

In the year 2023 DBG's representatives at the institutes and universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Zahide Aslan (Goethe Universität Frankfurt)
Regulation of heat stress-responsive genes by class B heat stress transcription factors in tomato

Christopher Bell (Universität Münster)
Resolving tissue-specific responses of subcellular redox and calcium dynamics in Arabidopsis thaliana in response to low oxygen stress

Tobias Blank (Leibniz Universität Hannover)
Analysis of secondary metabolites and their induction by salinity in hairy roots of Lycium humile

Panagiotis Boumpas (Universität Heidelberg)
Investigating the RNA-binding ability of the homeodomain-containing transcription factor WUSCHEL in Arabidopsis thaliana

Hannah Callenius (Universität Heidelberg)
Investigating the Cysteine Synthase Complex in regulating the ABA-dependent stomatal closure and the drought stress response

Philipp Feichtlbauer (Paris Lodron Universität Salzburg)
Gliding zones in plants: a review and a case study of physical and chemical properties in Ceropegia sandersonii trap flowers

Rune Hansen (Christian-Albrechts-Universität zu Kiel, CAU)
Comparative RNASeq analysis of the Aegilops cylindrica – Zymoseptoria tritici pathosystem in compatible and incompatible interactions

Tilman Jacob (Martin-Luther-Universität Halle-Wittenberg)
Analyses of DNA binding activities of PIF4 haplotypes and mutants

Sabiha Lakehsar (Universität Kassel)
Genetische Diversität und Klonalität von Vaccinium uliginosum (L.) und Vaccinium oxycoccos (L.) in hessischen Reliktpopulationen

Bastian Liese (Universität Bielefeld)
Effects of microplastics on plant quality traits of Brassica oleracea var. Sabauda

Marius Munschek (Universität Leipzig)
Putting Conservation Gardening into practice - An interactive database of endangered plant species in Germany

Swenia Paul (Carl von Ossietzky-University Oldenburg)
Two is better than one! A didactic concept for teaching the fertilization process of angiosperms using models and co

Jan Paulini (Rheinisch-Westfälische Technische Hochschule Aachen, RWTH)
Root-colonizing Pseudomonads confer salt tolerance in plants

Malwina Pluta (Christian-Albrechts-Universität zu Kiel, CAU)
Quantification of secondary metabolites in susceptible and resistant quinoa lines against downy mildew (Peronospora variabilis) and development of molecular markers

Andreas Reitmeier (Karlsruher Institut für Technologie, KIT)
Populationsdynamik der gynodiözischen Pflanzen Salvia pratensis und Salvia nemorosa basierend auf Blüten und Blütenentwicklungsgenen

Kristina Rosenzweig (Friedrich-Alexander-Universität Erlangen-Nürnberg, FAU)
Investigation of further resistance factors of Solanum lycopersicum against Cuscuta reflexa 

Rebecca Schulzke (Philipps-Universität Marburg)
The importance of ABA signalling for the interaction of Arabidopsis thaliana and Colletotrichum higginsianum

Mirjam Thielen (Rheinische Friedrich-Wilhelms-Universität Bonn)  
Establishing cytosolic C-to-U RNA editing in Physcomitrium patens and investigating the influence of knocked out DYW-type pentatricopeptide repeat editing factors under various stress conditions

Inken Thiemann (Universität Rostock)
Beeinträchtigt die Schließzell-spezifische Manipulation der SBPase die Bewegungen der Stomata?

Eduard Windenbach (Ludwig-Maximilians-Universität München)
Characterization of chloroplasts energy flux via NAD(P)H pools

Christopher Bell's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Münster in the year 2023 with the title:

Resolving tissue-specific responses of subcellular redox and calcium dynamics in Arabidopsis thaliana in response to low oxygen stress

Christopher Bell developed an experimental setup that enables real-time imaging of the stress responses of plant tissues at the confocal microscope under targeted and controlled oxygen deprivation.

Low oxygen conditions represent a major abiotic stress for plants, for instance during flooding. The lack of molecular oxygen as final electron acceptor arrests the mitochondrial electron transport chain and, as a direct consequence, ATP production. In order to investigate the mechanisms of plant acclimation to hypoxic stress, Bell developed a setup at the confocal microscope to image calcium dynamics in real time and in vivo. Using this setup, he demonstrates that low oxygen conditions are perceived rapidly by the plant which is reflected in a distinct calcium response. Furthermore, he investigated the effects of low oxygen conditions on the cellular redox homeostasis (NADPH:NADP⁺, H₂O₂ and glutathione redox potential). Bell's results indicate that the reduction state of these three redox active systems depends largely on the central metabolism and vary depending on the environmental oxygen conditions. He anticipates that the novel imaging setup could be a strong new asset for the field of plant low oxygen research. His findings highlight that calcium signalling and metabolic flexibility are important factors in plants facing hypoxic stress and contribute to the understanding of plant biology under hypoxia.

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Christopher Bell conducted this work at the Institute of Plant Biology and Biotechnology in the working group of Prof. Dr. Markus Schwarzländer.

Swenia Paul's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Carl von Ossietzky-University Oldenburg in the year 2023 with the title:

Two is better than one! A didactic concept for teaching the fertilization process of angiosperms using models and co.

Swenia Paul developed an innovative hands-on model that teaches the fertilization process of angiosperms, which can be used both for demonstration and for independent study.

The observation by teachers at the University of Oldenburg showed that the fertilization process of angiosperms is difficult for many students. This was taken as an opportunity to investigate the teaching of the fertilization process and the sustainability of learning success. Based on an analysis of the available models and textbooks used to teach the fertilization process, a lack of suitable, target group-oriented, didactic teaching materials was identified. In addition, the results of an online survey of biology students at University of Oldenburg revealed specific difficulties that can arise in connection with double fertilization.
Therefore, a didactic concept was developed, with a hands-on functional model at its center. The model was made of wood. The cells involved in the fertilization process are represented by removable components. They can be flexibly attached to the model body with magnets and moved along the model. This makes it possible to illustrate the fertilization process by simulating it on the model. The model can be used by teachers to explain the fertilization process demonstratively using the model. Learners can also actively practice the fertilization process themselves on the model. The model can be used by teachers to explain the fertilization process demonstratively with the help of the model. Learners can also actively practice the fertilization process themselves using the model. Interactive instructions and appropriately designed worksheets provide support. The model is currently being used in plant science courses at the University of Oldenburg, among others.
The work is intended to serve as an impulse for university teaching and learning to reflect on their own role. In doing so, existing, proven teaching materials can be questioned in order to open up one's own teaching and enable individualized, self-regulated teaching.

Read more in Paul's master thesis: https://cloudstorage.uni-oldenburg.de/s/bYZkQojxYQ2yD2M

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Swenia Paul conducted this work in the Institute for Biology and Environmental Sciences in the working group Biodiversity and Evolution of Plants of Prof. Dr. Dirk Albach.

Hannah Callenius's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Heidelberg in the year 2023 with the title:

Investigating the Cysteine Synthase Complex in regulating the ABA-dependent stomatal closure and the drought stress response

The master thesis showed an influence of the stability of the cysteine synthase complex during metabolic changes in cysteine metabolism during stomatal closure in Arabidopsis thaliana.

Due to the increasing extent and severity of droughts, it is very important to understand the response to drought stress in plants, which includes rapid stomatal closure to reduce water loss. Cysteine, the precursor of organic sulfur-containing molecules, can induce stomatal closure in Arabidopsis thaliana. Cysteine synthesis in three cellular compartments – the plastids, mitochondria and cytosol – requires the formation of the Cysteine Synthase Complex (CSC), a dynamically associating and dissociating protein complex of two enzymes.
This thesis focused on the role of the CSC in drought signalling and stomatal closure. Callenius analysed plants lacking the compartment-specific CSC proteins and transgenic plants with mutated CSC proteins that enhanced the stability of the protein complex. Callenius used microscopic and physiological methods to directly and indirectly determine the stomatal aperture and the accumulation of the drought hormone abscisic acid (ABA), and ultra-performance liquid chromatography (UPLC) to quantify the levels of sulfur-containing metabolites. Plants with a stabilised CSC association increased steady-state cysteine levels and induced stomatal closure, coinciding with a reduction in water loss and stomatal conductance. Using various Arabidopsis mutants, Callenius specified that this stability-induced response requires ABA and cysteine synthesis. Taken together, the results highlight a regulatory role for CSC stability during stomatal closure in response to drought signals.

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Hannah Callenius conducted this work at the Centre for Organismal Studies (COS) Heidelberg, Department Molecular Biology of Plants, in the group of Prof. Rüdiger Hell.

Panagiotis Boumpas's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Heidelberg in the year 2023 with the title:

Investigating the RNA-binding ability of the homeodomain-containing transcription factor WUSCHEL in Arabidopsis thaliana

For the first time, Panagiotis Boumpas described a so-far-unknown and novel RNA-binding ability of the Arabidopsis thaliana stem cell regulator WUSCHEL and identified candidate RNA binding targets of the protein.

In the shoot apical meristem of Arabidopsis thaliana, the homeodomain-containing transcription factor WUSCHEL (WUS) is required to specify stem cell identity. So far, most studies aiming to decipher the molecular mechanism of WUS have focused on its known DNA-binding ability. However, various studies have already reported on the RNA-binding ability of known homeodomain-containing transcription factors in different organisms. Hence, we hypothesized that WUS might also be able to associate with RNA via its conserved homeodomain.

In order to identify transcripts bound by WUS, we took advantage of RNA immunoprecipitation (RIP) followed by high-throughput sequencing. The RIP protocol Boumpas established using Arabidopsis thaliana seedlings overexpressing WUS as starting material allowed for co-immunoprecipitating WUS along with its bound RNAs.

Bioinformatic analyses of RIP-Seq data demonstrated that WUS associates with mostly exonic regions of hundreds of protein-coding transcripts. Genes which the RNAs bound by WUS are transcribed from were enriched for various biological processes known to be regulated by WUS. Moreover, bound transcripts were enriched in mobile messenger RNAs, indicating a possible role of WUS in RNA trafficking. Finally, Boumpas highlighted that genes bound by WUS both at the chromatin and transcript level are enriched for similar biological processes, further suggesting a possible tight connection between the different molecular functions of WUS towards common biological outcomes.

In conclusion, Boumpas described a so-far-unknown and novel RNA-binding ability of WUS. In the future, the results obtained will constitute a solid basis to precisely decipher the biological function behind the RNA-binding ability of WUS in order to better understand plant stem cell regulation.

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Panagiotis Boumpas conducted this work at the institute Centre for Organismal Studies (COS) Heidelberg, Department of Stem Cell Biology in the working group of Prof. Dr. Jan Lohmann.

Jan Paulini's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rheinisch-Westfälische Technische Hochschule Aachen (RWTH) in the year 2023 with the title:

Root-Colonizing Pseudomonads Confer Salt Tolerance in Plants

Paulini established a new hydroponic system to monitor and compare the physiological status of sugar beets (Beta vulgaris) under salt stress conditions and thereby provided the means to investigate and prove the significant salt stress alleviating capabilities of the tested plant growth-promoting rhizobacteria.

The sugar beet (Beta vulgaris) is a globally important crop, with 35 % of worldwide sugar production derived from it. It also provides essential raw materials for livestock feed and bioethanol. Due to unsustainable farming practices and rising temperatures, sugar beets frequently suffer from drought and soil salinization. These abiotic factors are the most significant limitations on sugar beet yield, causing a 33 % yield loss on average.
This study established a new system to monitor and compare the physiological status of B. vulgaris under salt stress conditions. The setup provided the means to investigate the salt stress alleviating capabilities of the PGPR Pseudomonas sp. TE7 from the Pseudomonas mandelii subgroup and Pseudomonas sp. TE13 from the Pseudomonas fluorescens subgroup.
The sugar beets were grown in a hydroponic system and in sand in the greenhouse while treated with the respective bacteria strains. Salt stress was applied to the plants, and the stress responses and bacteria-related response alterations were analysed. The bacteria were tested to be present on sugar beet roots during the evaluated 21 days. Inhabitation of the plant led to significant plant growth promoting and salt stress alleviating influence on sugar beets. Thus, both strains increased the relative leaf water content and the dry weight of salt-stressed sugar beets. Particularly, Ps. sp. TE13 had a distinct impact on the fitness of the photosynthesis machinery of salt-stressed plants, enhancing its efficiency, the capacity, and the effective quantum yield of the photosystem II while additionally increasing the photo pigment concentrations in unstressed plants. In contrast, Ps. sp. TE7 mitigated the photochemical energy dissipation.
Furthermore, quantitative real-time PCR led to the discovery that both strains induced an elevation in ascorbate peroxidase coding gene expression in sugar beets exposed to salt stress. These findings indicate that Ps. sp. TE13 and Ps. sp. TE7 can alleviate the negative implications of the natural stress response of B. vulagris to salinity. This contributes to the emerging field of plant-microbe interactions, which has the potential to enhance crop productivity and resilience, paving the way for more eco-friendly and effective agricultural strategies in the face of a changing climate and increasing food demands.
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Jan Paulini conducted this work at the Institute of Plant Physiology in Prof. Dr. Uwe Conrath’s group.

Kristina Rosenzweig's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Friedrich-Alexander-Universität Erlangen-Nürnberg in the year 2023 with the title:

Investigation of further resistance factors of Solanum lycopersicum against Cuscuta reflexa 

The cultivated tomato Solanum lycopersicum has more than just one resistance mechanisms to defend itself against the parasitic plant Cuscuta reflexa.

Cuscuta reflexa is a parasitic plant causing severe crop and yield damage every year. The parasite has neither leaves nor roots and is therefore absolutely dependent to withdraw nutrients and water from its hosts. For that, Cuscuta builds intrerspecific connections to the hosts vasculature. The host spectrum of C. reflexa includes nearly all dicotyledonous plants. One major exception is the cultivated tomato, Solanum lycopersicum. It possesses the Cuscuta receptor 1 (CuRe1), which enables the plant to recognize Cuscuta and induces a defense response. However, there is rising evidence that CuRe1 is not the only mechanism leading to immunity.

In the course of this thesis, several candidate genes were investigated regarding their role in the defense mechanism of S. lycopersicum. More detailed, several CRISPR-Cas9 derived transgenic tomato plants were used, each having a mutation in the corresponding candidate genes. Via infection of these lines with C. reflexa, one gene could be identified whose mutation led to the loss of resistance. The identified gene encodes a protein which is part of the ethylene pathway; an important pathway playing a role in many immune responses. Further investigations via qRT-PCR experiments revealed that the gene is slightly overexpressed in the mutant plants in comparison to the resistant wildtype plants. Additionally, it was shown that the candidate gene is also upregulated in the susceptible wild tomato variety, S. pennellii. This indicates that a low expression of the gene might be related to a higher resistance. In conclusion, a possible working mechanism of the gene in the defense mechanism of S. lycopersicum has been proposed: it might be possible that an overexpression of the gene might lead to an ethylene insensitivity, resulting in a lower immune response. In contrast, a downregulation of the gene might lead to an ethylene hypersensitivity, leading to an increased immunity.

However, this hypothesis has to be verified and further experiments have to be performed regarding this research area.

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Kristina Rosenzweig conducted this work at the Division of Molecular Plant Physiology in the group of Prof. Dr. Markus Albert.

Tilman Jacob's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Halle University in the year 2023 with the title:

Analyses of DNA binding activities of PIF4 haplotypes and mutants

Tilman Jacob established an in vitro assay to investigate the binding of different naturally occurring PIF4 haplotypes to the promoter of YUCCA8.

Understanding the molecular adaptation mechanisms of plants to increased ambient temperatures is crucial for the generation of future crops which are resilient to global warming. In the model plant Arabidopsis thaliana, the transcription factor PHYTOCHROME INTERACTING FACTOR 4 (PIF4) is a major coordinator of growth and development in response to light and temperature.

To make use of the natural genetic variation among different Arabidopsis ecotypes for the investigation of PIF4’s molecular function, a set of six naturally occurring PIF4 haplotypes was selected that assemble different combinations of frequently occurring single nucleotide polymorphisms (SNPs). Jacob established a pipeline for the recombinant expression of these PIF4 haplotypes in Escherichia coli and performed in vitro electrophoretic mobility shift assays (EMSAs) to study their DNA binding activities using the YUCCA8 promoter (pYUC8).

He could demonstrate that all evaluated natural PIF4 haplotypes were able to specifically bind pYUC8, in contrast to an artificially created PIF4 mutant with disrupted DNA-binding domain. Binding activities varied among the assessed natural haplotypes, but the assay was not robust enough to detect reproducible quantitative differences.

Nevertheless, the results represent a starting point for a more comprehensive molecular analysis of the PIF4 haplotypes, which will contribute to the overall understanding of PIF4’s molecular function and extend Arabidopsis thermoregulation research beyond the exclusive investigation of the Col-0 accession.

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Tilman Jacob conducted this work at the institute for agricultural and nutritional sciences (IAEW) in the crop physiology laboratory of Prof. Dr. Marcel Quint, under the supervision of Dr. Lennart Eschen-Lippold.

Mirjam Thielen's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bonn University in the year 2023 with the title:

Establishing cytosolic C-to-U RNA editing in Physcomitrium patens and investigating the influence of knocked out DYW-type pentatricopeptide repeat editing factors under various stress conditions

For the first time Thielen showed, that cytidine-to-uridine RNA-editing, which is naturally restricted to plant chloroplasts and mitochondria, is principally possible also in the cytosol using the moss Physcomitrium patens as a model system.

Plant-type cytidine-to-uridine RNA editing is performed by nuclear encoded RNA-binding pentatricopeptide repeat (PPR) proteins and affects transcripts in the mitochondria and chloroplasts but is suspiciously absent in the nucleo-cytosolic compartment. To investigate whether RNA editing factors could principally perform RNA editing in the cytosol, too, recombinant constructs of three characterized editing factors and their co-transcribed targets were transformed into Physcomitrium patens using an inducible expression setup. Cytosolic C-to-U RNA editing could be verified not only for the native targets artificially provided but also for up to hundreds of off-targets in the moss background transcriptome. The latter finding demonstrates restricted target recognition specificity and likely explains why plant RNA editing is restricted to the smaller transcriptomes of the endosymbiotic organelles in nature. However, the now available conservation profiling of off-targets will help to elucidate the details of PPR-RNA interactions towards possible future biotechnical approaches to engineer transcriptome targeting.

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Mirjam Thielen conducted this work at the Institute for Cellular and Molecular Botany in the research group Molekulare Evolution of Prof. Dr. Volker Knoop.

Zahide Aslan's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Frankfurt University in the year 2023 with the title:

Regulation of heat stress-responsive genes by class B heat stress transcription factors in tomato

Aslans work provides first evidence that the formation of a putative HsfA1a-HAC1-HsfB1 ternary activator complex might be important for the acetylation of histone 3 (H3K9ac), thereby directly linking the transcription factor function to chromatin changes that are related to transcription – a link that is currently not well described regarding heat stress response.

The response to heat stress is dependent primarily on changes in gene expression. Genes coding for survival of the cell are essential and need to be synthesized promptly. Transcription factors play central role, but their activity is associated with chromatin structure: the complex of DNA and proteins within the cell nucleus. This association influences how accessible specific genes are for transcription, impacting the cell's ability to rapidly produce the necessary proteins for survival during heat stress. Using transcription factor activator assays in isolated tomato protoplasts in combination with CRISPR-mediated mutation Aslan showed that class B heat stress transcription factors (HSF) can act as co-activators in the presence of histone acetyltransferases. This was also supported by expression analysis in plants in which HSFB1 was overexpressed using a pharmacological approach, by application of chemicals that either inhibit the activity of histone acetyltransferases or the activity of de-acetyltransferases. Importantly using chromatin immunoprecipitation assay Aslan showed that the alterations in gene expression are associated with changes in histone acetylation in HSF-target genes. These findings provide evidence that the activity of a transcription factor can be directly linked to chromatin structure and thereby contribute to the global changes in gene expression under heat stress.  

Read Master thesis: https://www.bio.uni-frankfurt.de/58896237/Heat_Stress

Read paper: Guarino F, Cicatelli A, Castiglione S, Agius DR, Orhun GE, Fragkostefanakis S, Leclercq J, Dobránszki J, Kaiserli E, Lieberman-Lazarovich M, Sõmera M, Sarmiento C, Vettori C, Paffetti D, Poma AMG, Moschou PN, Gašparović M, Yousefi S, Vergata C, Berger MMJ, Gallusci P, Miladinović D and Martinelli F (2022) An Epigenetic Alphabet of Crop Adaptation to Climate Change. Front. Genet. 13: 818727. doi: 10.3389/fgene.2022.818727

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Zahide Aslan conducted this work at the Institute of Molecular Biosciences in the working group led by Dr. Sotirios Fragkostefanakis focusing on the molecular and cellular mechanisms in plants.

Marius Munschek's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Leipzig University in the year 2023 with the title:

Putting Conservation Gardening into practice - An interactive database of endangered plant species in Germany

For the first time, Munschek examines the potential of conservation gardening as a participatory nature conservation measure for the preservation of endangered plant species in Germany and provides citizens with a list of endangered plant species suitable for gardening in the form of an interactive database.

In this study, Munschek presents a workflow using Germany as a case study to obtain information on endangered plant species regarding their amenability for conservation gardening, their ecological requirements for gardening, and commercial availability. Therefore, he synthesized the Red Lists of all 16 federal states in Germany, and text-mined a comprehensive platform for garden plants, as well as multiple German producers of native plants. To provide accessible information, Munschek developed a user-friendly app that offers region-specific lists of CG plants, along with practical guidance for planting and purchasing. The findings reveal that a median of 845 plant species are red-listed across federal states (ranging from 515 to 1123), with 41% of these species amenable to gardening (ranging from 29 to 53%), resulting in a total of 988 CG species. Notably, 66% of these species (650) are already available for purchase. Additionally, he observed that many CG plants exhibit drought tolerance and require less fertilizer on average. With a multitude of declining plants amenable to gardening and the vital role of gardens as refuges and green corridors, CG holds substantial potential to catalyze transformative change in bending the curve of biodiversity loss.

Link to the App: https://conservation-gardening.shinyapps.io/app-en/

Paper: Munschek, M., Witt, R., Kaltofen, K. et al. Putting conservation gardening into practice. Sci Rep 13, 12671 (2023). https://doi.org/10.1038/s41598-023-39432-8

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Marius Munschek conducted this work at the Institute of Special Botany and Functional Biodiversity in the working group of Prof Alexandra Weigelt and Prof Christian Wirth.

Bastian Liese's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bielefeld University in the year 2023 with the title:

Effects of microplastics on plant quality traits of Brassica oleracea var. sabauda

This study shows the importance of plastic type, particle size and concentration on the uptake and effects of microplastics on plant traits.

The contamination of soils with microplastics and the resulting effects on terrestrial ecosystems and plants are major concerns of the 21^st century.

Therefore, this study was conducted to investigate effects of contamination of the soil substrate with polyethylene (PE) and polystyrene (PS) microplastics differing in particle size and concentration on different plant traits using the crop plant Brassica oleracea var. sabauda. PS particles were additionally recorded in B. oleracea var. sabauda seedlings using coherent anti-Stokes Raman scattering (CARS) microscopy.

Plastic type, particle size and concentration showed distinct effects on certain plant traits. The rate of assimilation and transpiration tended to differ depending on plastic type and size class. Overall amino acid composition and concentrations in the leaves were likewise not affected, but the leucine concentration was significantly increased in the microplastic-exposed plants.

The effects of microplastic exposure could have far-reaching consequences for terrestrial ecosystems. The exposure of B. oleracea var. sabauda to microplastics showed in this study a stress response. Due to the ubiquity of microplastics, further research on their impact is necessary to assess their importance for ecosystems, agriculture and human health.

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Bastian Liese conducted this work at the Faculty of Biology at Bielefeld University in the working group for chemical ecology led by Prof Dr Caroline Müller.

Rebecca Schulzke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Marburg University in the year 2023 with the title:

The importance of ABA signalling for the interaction of Arabidopsis thaliana and Colletotrichum higginsianum

The present work on the interaction of the model plant Arabidopsis thaliana and the hemibiotrophic fungus Colletotrichum higginsianum provides some indication for a potential novel mechanism for the suppression of early defense signals by the phytohormone abscisic acid (ABA).

The phytohormone abscisic acid (ABA) is produced in response to abiotic stress factors such as cold, drought or osmotic stress. The role of ABA in plant resistance to pathogens has not been fully understood, since both negative and positive effects have been described depending on the plant-pathogen system investigated. To better understand the role of ABA in plant resistance, mutants of the model plant Arabidopsis thaliana that were either defective in ABA production or perception were employed and their defense response to infection with the hemibiotrophic fungal pathogen Colletotrichum higginsianum was characterized.
During the necrotrophic phase of the interaction, ABA-deficient A. thaliana mutants showed increased resistance towards C. higginsianum compared to the wild type. Since C. higginsianum is sensitive to the salicylic acid (SA) regulated defense response during the preceding biotrophic phase, the levels of SA and its downstream metabolites were determined by HPLC. The increased resistance of the ABA-deficient mutants at 3.5 days post infection (dpi) was preceded by increased levels of SA and its metabolite 2,3-dihydroxybenzoic acid (DHBA) during the early biotrophic phase at 2 dpi. Further analysis on the role of ABA for the regulation of SA metabolism suggested an antagonistic interaction between ABA and SA in the pathosystem studied, in which ABA may specifically suppress the SA response during the early biotrophic phase by attenuating 2,3-DHBA production and glycosylation. Whether increased DHBA levels play a functional role in the immune response or are consequences of increased SA production is not yet sufficiently clear and requires further research.
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Rebecca Schulzke conducted this work at the Philipps University of Marburg, Chair of Molecular Plant Physiology in the working group of Professor Dr. Lars Voll.

Malwina Pluta's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Kiel University in the year 2023 with the title:

Quantification of secondary metabolites in susceptible and resistant quinoa lines against downy mildew (Peronospora variabilis) and development of molecular markers

This study formed part of the first attempt to develop molecular markers and to identify metabolic biomarkers that could be used for downy mildew resistance screening in quinoa.

Downy mildew caused by oomycete Peronospora variabilis is the most devastating of diseases in quinoa that significantly reduces the yield of this crop in favourable climatic conditions. In this study, I developed four PCR-based markers for previously identified QTL ms5.1 associated with downy mildew resistance [1]. Moreover, I identified a cluster of putative resistance genes in proximity with informative markers in the reference genome of quinoa.
For the second experiment, I extracted the metabolites from resistant and susceptible quinoa plants following the SIMPLEX procedure. Further, I quantified the metabolites using a Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) system and identified them using the constructed metabolic database. The accumulation trend of several metabolites suggested candidates that likely contribute to increased downy mildew resistance; of them, many belonged to the class of phenolics and lipids.
The results from both experiments, pending verification in follow-up experiments, directly impact the advancement of quinoa breeding.
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[1] Maldonado-Taipe, N., Barbier, F., Schmid, K., Jung, C., & Emrani, N. (2022). High-Density Mapping of Quantitative Trait Loci Controlling Agronomically Important Traits in Quinoa (Chenopodium quinoa Willd.). Frontiers in Plant Science, 13. https://doi.org/10.3389/fpls.2022.916067

The thesis is available upon request from Central Library of Kiel University under: https://www.ub.uni-kiel.de/en/ordering-borrowing

Malwina Pluta conducted this work at the Institute of Agronomy and Plant Breeding (head: Prof. Dr. Christian Jung) in Dr. Nazgol Emrani's working group.

Rune Hansen's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at xxUniversity in the year 2023 with the title:

Comparative RNASeq analysis of the Aegilops cylindrica – Zymoseptoria tritici pathosystem in compatible and incompatible interactions

Rune Hansen used RNASeq data to generate the first de novo transcriptome assembly of the close wheat relative Aegilops cylindrica during compatible and incompatible interactions with the agriculturally important wheat pathogen Zymoseptoria tritici to identify a potential new source of resistance genes.

Wheat is one of the most important crops for feeding a growing world population. In addition to climate change, the crop is also strongly influenced by the pathogen Zymoseptoria tritici (Ascomycota). In this work, the wild plant Aegilops cylindrica, which is closely related to wheat, was used as a host to perform compatible and incompatible infection experiments with different Z. tritici genotypes. At different time points of infection, some leaves were harvested and their RNA isolated. Using bioinformatic techniques, a de novo transcriptome assembly was generated to search for significantly differentially expressed genes that induce resistance in the incompatible interactions. Surprisingly, many known resistance genes (e.g. leucine rich repeat (LRR)-domain-containing proteins) and resistance-inducing genes (e.g. pathogenesis-related (PR) genes or various transcription factors) were strongly expressed, especially in the compatible interactions, without inducing resistance in the plants at all. During the incompatible interaction, only a few genes were found to be differentially expressed compared to the untreated plants and also differing from the expressed genes of the compatible interactions. Among other resistance gene candidates, a gene coding for a lipid transfer protein seems to be particularly promising. This gene is only downregulated during the compatible interaction. In addition, a transcription factor of the WRKY family was identified that could act as a susceptibility factor during the compatible interaction. In summary, this work illustrates the potential utility of previously unexplored wild plants as a source of new agriculturally important resistance genes and provides a basis for studying the effects of mutations in the newly discovered resistance genes in genetic engineering experiments.
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Rune Hansen conducted this work at the Botanic Institute in the working group of Prof. Dr. Eva Stukenbrock.

Sabiha Lakehsar's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Kassel University in the year 2023 with the title:

Genetische Diversität und Klonalität von Vaccinium uliginosum (L.) und Vaccinium oxycoccos (L.) in hessischen Reliktpopulationen

Peatland plant species that are rare in Hesse exhibit extreme genetic impoverishment locally, which further increases the risk of extinction due to a lack of adaptability.

Most Hessian peatlands and peatland-like habitats are naturally small in size and spatially isolated from one another. Historical use has further decimated these areas. Nowadays, the consequences of climate change are increasing the pressure on these sensitive habitats and the species associated with them. As part of this project, population genetic studies were performed on two species of peatland plants that are rare in Hesse, the small cranberry (Vaccinium oxycoccos), which is locally in sharp decline, and the bog bilberry (Vaccinium uliginosum), which has always been rare in Hesse. It has been shown that the only populations of both species in northern Hesse have almost no genetic diversity. The last remaining population of the small cranberry in the Reinhardswald consists of only three genetically very similar clones, while the only two populations of bog bilberry consist of a single and three closely related clones respectively. By comparing this data with results from larger, more vital populations in southern Lower Saxony and central Hesse, recommendations for specific conservation measures in the relict populations in northern Hesse can be derived.

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Sabiha Lakehsar completed the work in the botany working group of Prof. Dr. Birgit Gemeinholzer under the supervision of Dr. Daniela Guicking.

Eduard Windenbach's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ludwig-Maximilians-Universität Munich (LMU) in the year 2024 with the title:

Characterization of chloroplasts energy flux via NAD(P)H pools

Windenbach developed novel, elegant assays that enable the determination of co-enzyme specificity of the electron transfer in chloroplasts via simultaneous reaction.

Chloroplasts of Arabidopsis thaliana possess two malate dehydrogenases (MDHs), which were previously assumed to act in separated diurnal phases. The MDH isoforms utilize either NADPH/NADP+ or NADH/NAD+ for their reaction and allow an independent energy flux from the respective coenzyme pools. Windenbach developed an enzyme assay that enabled the simultaneous measurement of the activity of both malate dehydrogenases. The coenzyme derivative Ti-NADH was used in the measurement, which absorbs at a different wavelength than NAD(P)H and allowed for simultaneous measurement of plNAD-MDH and NADP-MDH activity. Here it was shown that C₃ plants have a higher activity for the light-independent plNAD-MDH. Furthermore, by using in-gel assays, the presence of different plNAD-MDH complexes and their activity was shown. All in all, the work makes an important contribution to a better understanding of the energy flow across the NAD(P)H pools of the chloroplast and provides new insights into an alternative role of plastid MDHs.

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Eduard Windenbach conducted this work at the LMU Chair of Plant Biochemistry and Physiology in the working group of Prof. Dr. Hans-Henning Kunz.

In the year 2024 DBG's representatives at the universities evaluated master theses in plant sciences. The following persons received the award (in alphabetical order):

Sarah Gabelmann (Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau, RPTU)
Mapping of the nuclear proteome in Chlamydomonas reinhardtii using TurboID-mediated proximity labeling

Javier García Varo (Karlsruhe Institute of Technology, KIT)
Functional characterization of the terpene synthase ZmTPS2 in TBY-2 cells

Carolin Goldhardt (Martin-Luther-Universität Halle-Wittenberg)
Study on the mitochondrial localisation of the protein mTERF21 and on RNAs associated with mTERF21 in vivo in Arabidopsis thaliana

Marie Hoensbroech (Carl von Ossietzky Universität Oldenburg)
What goes up, must come down? Vertical wind dispersal of epiphyte seeds in a Panamanian rainforest

Anne Jaczkowski (Gottfried Wilhelm Leibniz Universität Hannover)
From single steps to complex pathways – elucidating biosynthetic processes via heterologous expression in Nicotiana benthamiana

Vincent Kaltenbach (Universität Münster)
Investigation of the oxidosqualene cyclase family from Arabidopsis thaliana

Arno Krieger (Universität Bielefeld)
Mitigating transgene silencing in C. reinhardtii – Examining synergisms of transgene silencing factors through genome editing

Helen Landgraf (Universität Rostock)
Impact of the subcellular localization of SnRK1 on anthocyanin formation and high light acclimation in Arabidopsis thaliana

Tim Jacob Lange (Goethe Universität Frankfurt)
Analysis of chitosan perception and bioactivity in Arabidopsis guard cells

Tilman Linke (Universität Leipzig)
Development of Photo-Calorespirometry, as a Novel Method to Directly Access Photosynthetic Rates and Efficiencies of cyanobacteria in real-time

Samuel Nestor Meckoni (TU Braunschweig)
Establishing transformation methods in Utricularia gibba to investigate its potential as a biotechnological production system by examining trap specific secretion mechanisms

Inês Nunes (Ludwig-Maximilians-Universität München)
Gaining new insight into Plastid Envelope Ion Channel function by studying PEC1 gain-of-function mutants

Franziska Obert (Christian-Albrechts-Universität zu Kiel)
Translocation of cytosolic malate dehydrogenases from Arabidopsis thaliana upon abiotic stress

Robin Pelchen (Universität Hamburg)
The optimal vertical root profile under a changing climate – a model approach

Julia Retzlaff (RWTH Aachen University)
A synthetic biology approach to enhance wheat (Triticum aestivum) seed germination under low oxygen

Cay Christin Schäfer (Universität Bonn)
Crosstalk between the micronutrient boron and the phytohormone auxin on the level of polar auxin transport during primary root development of maize (Zea mays)

Nina Solia (Universität zu Köln)
The Role of Pseudomonas putida Cip1 in Plant-Microbe Interaction

Moritz Stegner (Universität Innsbruck)
How storage conditons affect ageing mechanisms of seeds

Lilith Weissflog (Universität Hohenheim)
Effects of light cycle and air humidity on root exudates and water balance of maize (Zea mays L.)

Allegra Wundersitz (RWTH Aachen University)
Exploring the role of long-chain acyl-CoA esters in ACBP1-RAP2.12 complex stability

Lilith Weissflog's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Hohenheim in the year 2024 with the title:

Effects of light cycle and air humidity on root exudates and water balance of maize (Zea mays L.)

Integration of the natural daily variation of relative humidity increased onset and intensity of drought stress in maize cultivated in climate chambers

Cultivation of maize is influenced by light and water availability. In the field, light and relative humidity change continuously throughout the day, but this phenomenon is usually not taken into account in experiments in climate chambers. In this master thesis, the effects of (1) light diurnal variation on root exudation and (2) relative humidity (rH) on the intensity of drought stress were investigated.

For this purpose, maize plants were grown in soil columns in a climate chamber for a period of three weeks and exposed to drought stress during the last 8 days. Light and rH were either kept constant during the day or modeled on the natural diurnal cycle.

The timing of root exudate collection influenced the exudation of carbon and dissolved carbohydrates, which increased at high light intensity, while the exudation of phenols remained constant. A diurnal variation in rH led to earlier and more intense drought stress compared to constant rH, as evidenced by early leaf curling. This effect was particularly pronounced in the rth3 mutant, which cannot form normal root hairs.

It is known that field trials on drought stress and trials in climate chambers often do not provide comparable results. The results of this master thesis clearly show that the influence of the rH diurnal cycle in particular should be given more consideration in future climate chamber studies.

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Lilith Weissflog conducted this work at the Institute for Crop Science 340e in the working group of Prof. Dr. Christian Zörb.

Inês Nunes's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Ludwig-Maximilians-Universität München (LMU) in the year 2024 with the title:

Gaining new insight into Plastid Envelope Ion Channel function by studying PEC1 gain-of-function mutants

Nunes investigated the effects of a PEC1 gain-of-function mutant, potentially linking defects in photosynthesis, and rRNA maturation to plastid ion homeostasis

This study explored the role of the plastid ion channel PEC1 through analysis of the pPEC1-mV gain-of-function mutant, focusing on its effects on photosynthesis and ion homeostasis in plastids. The pPEC1-mV mutant displayed a distinct virescent phenotype and impaired photosynthesis, linked to reduced expression of photosynthesis-related proteins, as revealed through RNA-Seq and immunoblot analyses. Whether these effects are due to altered PEC1 channel function—potentially affected by the large fluorescent tag—or disrupted PEC1/2 protein interactions that impair complex formation remains unclear. Through a suppressor screen, we also identified a previously uncharacterized cation channel-like protein that could modulate pPEC1-mV phenotypes, presenting a promising target for future studies. This work provides valuable insights into the regulation of plastid ion homeostasis and its influence on chloroplast function.

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Inês Nunes conducted this work at the Institute of Biology at LMU Munich in the working group of Prof. Dr. Hans-Henning Kunz.

Julia Retzlaff's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at RWTH Aachen University in the year 2024 with the title:

A synthetic biology approach to enhance wheat (Triticum aestivum) seed germination under low oxygen

Is wheat able to germinate despite flooding? Using innovative synthetic biology approaches, we have found a way to enhance wheat’s germination ability under low oxygen conditions.

As climate change increases the frequency and duration of flooding, agriculture faces new challenges. This creates an urgent need for resilient crops that can thrive even during critical phases, such as germination, under adverse conditions. To enhance wheat seed germination under low-oxygen conditions, two innovative synthetic biology approaches were developed: through targeted genetic modifications, we generated wheat lines capable of initiating germination under oxygen-deficient conditions.

We combined DNA sequences from the rice and wheat genome to engineer genetic circuits that activate under low-oxygen conditions, aiming to regulate developmental processes such as germination. We tested these DNA constructs through transient transformation in protoplasts and in stable transgenic lines. Our results indicate that this approach is a promising strategy to enhance cereal germination under submergence.

Our findings provide valuable insights into the genetic and biochemical mechanisms involved in germination under hypoxic conditions. Our work contributes to understanding fundamental mechanisms for developing climate-resilient wheat varieties and provides a basis for future breeding strategies aimed at making agriculture more resilient to the impacts of climate change.

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Julia Retzlaff conducted this work at the department of biology at university of oxford in the working group of Prof. Dr. Francesco Licausi.

Allegra Wundersitz's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at RWTH Aachen University in the year 2024 with the title:

Exploring the role of long-chain acyl-CoA esters in ACBP1-RAP2.12 complex stability

Wundersitz investigated how long-chain acyl-coenzyme A (CoA) esters facilitate the dissociation of the transcription factor RAP2.12 from ACBP1, providing new insights into oxygen sensing and acyl-CoA signaling in plants.

Long-chain acyl-coenzyme A (CoA) esters are key signaling molecules that initiate the hypoxic stress response in plants by promoting the dissociation of the transcription factor RAP2.12 from ACBP1 at the plasma membrane. This thesis investigates the molecular mechanism underlying the acyl-CoA-mediated protein dissociation using in silico, in vivo, and in vitro approaches. Protein-protein interaction assays suggest that RAP2.12 binds to the acyl-CoA-binding domain of ACBP1. Molecular dynamics simulations suggest that unsaturated acyl-CoAs may block the RAP2.12 binding site, thereby facilitating its release. Additionally, an ACBP1 mutant with reduced acyl-CoA affinity was generated by targeted site directed mutagenesis, to further explore the role of the ACBP1-acyl-CoA interaction in signal transduction. Preliminary measurements indicate a reduced binding affinity, making this mutant a useful tool for upcoming experiments. Overall, this work provides foundational insights into acyl-CoA-mediated signal transduction and could eventually contribute to the development of new strategies to enhance stress resistance in plants.

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Allegra Wundersitz conducted this work at the Institute of Biology I, Molecular Ecology of the Rhizosphere, in the working group of Prof. Dr. Joost T. van Dongen.

Anne Jaczkowski's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Gottfried Wilhelm Leibniz Universität Hannover in the year 2024 with the title:

From single steps to complex pathways – elucidating biosynthetic processes via heterologous expression in Nicotiana benthamiana

This master's thesis combines complex bioinformatics and biotechnological methods with the objective of optimising the elucidation and heterologous reconstruction of the biosynthesis of specialized plant natural products - a project of great scientific relevance for the biotechnological production of plant-derived agents.

Natural plant products are of great importance to humans because of their diverse biological activities and therefore potential application in areas such as medicine, the food industry and agriculture. However, there are two central challenges for the biotechnological production of plant-based substances: elucidating their biosynthesis and recreating it in a suitable production organism. Deciphering single biosynthetic steps often proves to be extremely complex, comparable to searching for a needle in a haystack. To effectively reduce the effort involved in screening potential gene candidates through targeted pre-selection, this master's thesis employs complex bioinformatics methods such as orthogroup and phylogeny analyses. This approach is demonstrated for the synthesis of specific substances from the genus Allium, whose degradation products contribute to the characteristic smell and taste of these plants.

Furthermore, this master’s thesis deals with the question of how to improve the reconstruction of complex, multi-step biosynthetic pathways in the heterologous screening and production plant Nicotiana benthamiana. For this purpose, the method of Modular Cloning (MoClo) was used to bundle the transfer of several synthesis steps. In the future, this may not only facilitate the elucidation of subsequent biosynthesis steps, but also contribute to a more efficient biotechnological production of natural products in the heterologous system. In this context, the heterologous biosynthesis of quassinoids – complex natural products with potential applications as pharmaceuticals or pesticides – was exemplarily addressed.

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Anne Jaczkowski conducted this work at the institute of botany in the working group of Prof. Dr. Jakob Franke.

Moritz Stegner's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Innsbruck in the year 2024 with the title:

How storage conditons affect ageing mechanisms of seeds

This thesis provides new insights into how four different storage conditions affect seed ageing mechanisms involving reactive oxygen species (ROS), highlighting how cytoplasmic viscosity and molecular mobility impact seed ageing in five crop species.

Seed ageing is strongly influenced by reactive oxygen species (ROS) and storage conditions such as temperature and humidity. This thesis examined the seeds of five plant species (Allium cepa, Daucus carota, Lactuca sativa var. crispa, Cucumis sativus, and Raphanus sativus var. sativus) under controlled storage conditions: cold/dry (4°C / 37% RH), ambient/dry (22°C / 37% RH), and hot (45°C) under dry (40-20% RH) or humid (95% RH). Seed viability and vigor were evaluated with germination tests, while tocochromanols and lipid peroxidation markers were analyzed using HPLC and LC-MS/MS. Results showed that higher temperatures and humidity accelerated seed ageing, and that tocochromanols were depleted as a protective mechanism against oxidative damage during ageing. Notably, lipid peroxidation was most pronounced when cytoplasmic viscosity was low. These findings are valuable for improving our understanding of seed storage and longevity under varying environmental conditions.

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Moritz Stegner conducted this work at the department for botany in the working group of Ilse Kranner.

Nina Solia's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität zu Köln in the year 2024 with the title:

The Role of Pseudomonas putida Cip1 in Plant-Microbe Interaction

A protease inhibitor localized to the outer bacterial membrane might be involved in the colonization of maize roots by a plant-growth promoting rhizobacterium.

In Pseudomonas putida, a beneficial bacterium colonizing maize roots, the chagasin-like inhibitor Cip1 has been identified and demonstrated to inhibit maize root apoplastic Papain-like cysteine proteases (PLCPs). This Master Thesis aimed to investigate the cellular localization of Cip1 in P. putida and its potential role in root colonization. First, an in planta root colonization assay for maize was developed to evaluate root colonization by bacteria lacking Cip1. Our results show that within six days P. putida Δcip1 colonizes the root cortex as effectively as the wildtype indicating that Cip1 is not required for epiphytic colonization of maize roots. Second, we have successfully generated fluorescence-tagged P. putida strains containing a sfgfp genomic integration that can be used for further colonization studies. Finally, our localization experiments using cell fractionation and fluorescence microscopy have shown that Cip1 localizes to the outer bacterial membrane, confirming its lipoprotein prediction. These results lead us to the hypothesis that, upon endophytic colonization, Cip1 may prevent the release of microbial-associated molecular patterns from the bacterial cell surface by inhibiting PLCPs. Understanding the role of membrane-anchored Cip1 in plant colonization might provide insight into the strategies beneficial microbes use to colonize plants and might help in the application of beneficial microbes for plant protection.

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Nina Solia conducted this work at the institute of plant sciences in the working group of Prof. Dr. Gunther Döhlemann.

Javier García Varo's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Karlsruhe Institute of Technology in the year 2024 with the title:

Functional characterization of the terpene synthase ZmTPS2 in TBY-2 cells

This thesis attempted to elucidate the potential role of stromulation during in secondary metabolism by using the terpenoid synthesis pathway as a case study in the model system tobacco BY-2 cell culture.

Crosstalk between metabolic processes in cellular compartments enables cells to integrate signals and exchange metabolites, which is crucial for the regulation and production of vital compounds, as in the case of terpenes where multiple compartments are involved during the biosynthesis process.

To explore if stromules act as a metabolic conduit in terpene synthesis between compartments the generation of transgenic BY-2 cells overexpressing fluorescently labelled variants of the terpene synthase ZmTPS2 from maize was attempted. Furthermore, the subcellular location of terpenoid precursors was explored by performing a qualitative and quantitative colocalization analysis of synthetic, fluorescent analogues with the help of organelle dyes or fluorescent markers.  

The transgene was successfully integrated into the TBY-2 genome but did not show transcriptional activity and microscopic analysis was not possible. Colocalization of the fluorescent compounds show a strong overlapping signal in lipophilic environments like lipid droplets but low overlap in ER which was altered after treatment with Brefeldin A an inhibitor of protein transport. No overlap in peroxisomes was visible. In addition, the motility of precursors were explored through inhibiting actin-myosin movement showing independent movement of the fluorescent compound in the cell. Lastly, stromule frequency was altered during metabolic inhibition of MEP-pathway.

Therefore, this study may provide the fundament for further research about the connection of metabolic processes by organelle shape and hints at new functional aspects of stromulation.

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Javier García Varo conducted this work at the Joseph-Gottlieb Kölreuter Institute for Plant Sciences (JKIP) in the working group of Prof. Peter Nick.

Sarah Gabelmann's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau in the year 2024 with the title:

Mapping of the nuclear proteome in Chlamydomonas reinhardtii using TurboID-mediated proximity labeling

For the first time, a proximity labeling approach was used to characterize the nuclear proteome of the green alga Chlamydomonas reinhardtii under different conditions, leading to the identification of proteins potentially involved in the stress response to increased H₂O₂ production.

Nuclear proteins like transcription factors and other transcriptional regulators play an essential role in the regulation of gene expression, a complex process which controls the activities of the cell and allows it to acclimate to external stimuli and stress conditions. To analyze the protein composition of the nucleus under different conditions, a proximity labeling method that has only recently been established in Chlamydomonas reinhardtii was employed. This method utilizes TurboID, a variant of the Escherichia coli biotin ligase BirA, to activate biotin which then covalently attaches to amines of close-by proteins, allowing for the capturing of protein–protein interactions and mapping of proteomes in the living cell. Constructs driving the production of a nuclear-localized TurboID bait and a cytosolic TurboID control bait were generated and transformed into C. reinhardtii. After the functionality of the baits in the two compartments was confirmed by immunoblot analysis, in vivo proximity labeling experiments with externally added biotin were carried out. Mass spectrometry analysis of the purified biotinylated protein fraction revealed 852, 1,160 and 835 proteins significantly enriched for the nuclear bait under continuous light, heat stress and elevated H₂O₂ levels triggered by paraquat treatment, respectively. Furthermore, when the paraquat treatment was compared to the continuous light control condition, 20 proteins were found to be significantly enriched in the nucleus under increased H₂O₂ levels. These proteins might be involved in the response to oxidative stress, although further analysis is required to specify their role in the nucleus.

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Sarah Gabelmann conducted this work in the Biology department in the working group Molecular Biotechnology and Systems Biology of Prof. Dr. Michael Schroda.

Franziska Obert's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Christian-Albrechts-Universität zu Kiel in the year 2024 with the title:

Translocation of cytosolic malate dehydrogenases from Arabidopsis thaliana upon abiotic stress

During redox stress, cytosolic malate dehydrogenases from Arabidopsis thaliana translocate into the nucleus, where they perform a moonlighting function, thereby influencing the regulation of the redox state of the cell.

Malate dehydrogenases are particularly known for catalyzing the reversible conversion of L-malate to oxaloacetate. However, current research indicates that these enzymes can also perform moonlighting functions in the nucleus.

In this work, plasmids were generated to express fusion proteins of the three cytosolic malate dehydrogenases and a fluorophore in protoplasts of A. thaliana. This allowed the determination of the subcellular localization of the respective enzymes by fluorescence microscopy and the observation of translocation under the influence of abiotic stress induced by treatment with redox-active chemicals. To test whether a moonlighting function exists in the interaction with the transcription factor SOG1, experiments were performed using bimolecular fluorescence complementation.

It was shown that cytosolic malate dehydrogenases of A. thaliana are localized in the cytosol under normal conditions and undergo translocation into the nucleus upon treatment with various redox-active chemicals. Furthermore, an interaction of cytosolic malate dehydrogenase 2 with the transcription factor SOG1 was detected for the first time. SOG1 plays an important role in the cell's response to stress and, for example, initiates DNA repair or apoptotic processes. The results suggest that cytosolic malate dehydrogenases serve as sensors for the perception of fluctuations in redox homeostasis in plants. It is likely that conserved cysteine residues of cytosolic malate dehydrogenases, which can undergo different post-translational modifications depending on the redox state of the cell, play a crucial role.

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Franziska Obert conducted this work at the Botanical Institute of Christian-Albrechts-Universität zu Kiel in the working group of Prof. Dr. Jennifer Selinski.

Helen Landgraf's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Rostock in the year 2024 with the title:

Impact of the subcellular localization of SnRK1 on anthocyanin formation and high light acclimation in Arabidopsis thaliana

The differential localisation of SnRK1, a protein kinase essential for the regulation of energy homeostasis, between nucleus and cytosol affects primary and secondary metabolic reactions and thus influences development and growth.

The maintenance of energy homeostasis in plants during growth and under changing environmental conditions is enabled by a highly conserved protein kinase, the sucrose non-fermenting 1-related protein kinase (SnRK1). Under stress conditions, SnRK1 mobilises alternative energy sources through the post-translational and transcriptional regulation of catabolic and anabolic responses. A key to the action of SnRK1 is its variable localisation between the cell nucleus and the cytoplasm. Using physiological and molecular biological techniques such as qPCR, gas chromatography and LC-MS/MS analyses, the effects on metabolic and growth-specific parameters were determined in Arabidopsis thaliana mutants that accumulate the kinase in only one of these compartments. For example, the exclusive localisation of SnRK1 in the cell nucleus had a positive effect on growth. The results of this work suggest that SnRK1 localisation is important for the regulation of primary and secondary metabolism under acclimation-relevant conditions, which will be of economic importance in agriculturally important crops in the future.

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Helen Landgraf conducted this work at the institute for Bioscience in the working group of Jun.-Prof. Dr. Andreas S. Richter focusing on the physiology of plant metabolism.

Cay Christin Schäfer's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Bonn in the year 2024 with the title:

Crosstalk between the micronutrient boron and the phytohormone auxin on the level of polar auxin transport during primary root development of maize (Zea mays)

The polar localisation of the auxin transport protein PINFORMED1a in the maize root is altered under boron deficiency. This reveals that auxin transport is an important regulator of plant growth under boron deficiency. Schäfer's work supports the hypothesis that there is an interaction between boron and auxin on the level of polar auxin transport in the primary root of maize, making auxin an important factor regulating growth responses under boron deficiency in plants.

All essential nutrients are required in sufficient amounts for optimal plant growth. The micronutrient boron is one of these nutrients and is taken up by plants through the roots in form of boric acid. Many soils worldwide are deficient in boron, resulting in severe yield losses. To counteract these adverse effects, it is pivotal to understand the role of boron in plants. On the one hand, boron contributes to the stabilisation of the cell wall in plants. In addition, cell wall-independet functions of boron are suggested, such as interactions with plant hormones including auxin. Such interactions between boron and auxin were investigated in this master thesis in the crop plant maize. For this purpose, seedling assays were carried out in maize, firstly using a maize variety in which auxin transport is disrupted (Zmbarren inflorescence2). In addition, a chemical approach was applied using naphthylphthalamic acid (NPA), a chemical that inhibits auxin transport. Furthermore, cellular analyses with the fluorescent marker line ZmPINFORMED1a:YFP (ZmPIN1a:YFP) were performed to investigate the localisation of the auxin efflux transporter ZmPIN1a in the primary root of boron-deficient maize seedlings using confocal laser scanning microscopy. For all apporaches seedlings were grown under different boron conditions. These analyses aimed revealing a potential interaction between boron and auxin on the level of polar auxin transport and thus aid in further characterizing the role of boron in the plant. The mutant and the chemical approach using NPA provided no experimental evidence for interactions between boron and auxin transport during primary root development in maize. However, it was shown that boron deficiency leads to an altered localisation of the auxin efflux transporter ZmPIN1a:YFP, which may disrupt polar auxin transport and thus the establishment of auxin gradients. The results of this work support the hypothesis that interactions between boron and auxin play a role in maize primary root development. Further experiments should assess whether the delocalisation of the auxin efflux transporter occurs independently of cell wall defects.

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Cay Christin Schäfer conducted this work at the Institut für Nutzpflanzen und Ressourcenschutz - Crop Functional Genomics in the working group of Dr. Michaela Matthes in Professor Hochholdingers group.

Tim Jacob Lange's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Goethe Universität Frankfurt in the year 2024 with the title:

Analysis of chitosan perception and bioactivity in Arabidopsis guard cells

Chitosan treatments can improve the plant’s resistance against drought and pathogens. This work aimed to find how the plant’s receptors can perceive the chitosan molecules on a molecular level.

Chitosans are chitin-related biopolymers found in the cell walls of some plant pathogens. The application of chitosans to plants can improve their drought stress tolerance and pathogen resistance. However, less is known about how the plant’s receptors can perceive the chitosan molecules on a molecular level to induce these protective properties.

In this study, nine different chitosans were tested for their ability to induce receptor dimerisations between the proposed chitosan receptors in thale cress (Arabidopsis thaliana). To do so, a split-luciferase system was established in leaf protoplasts to follow along the chitosan-induced receptor dimerisations. Besides this, the different chitosans were tested on guard cells to define their bioactivities. With this, it was possible to explain the different bioactivities of the respective chitosans on the level of receptor interactions.

Hence, the results obtained here helped us understand how the plant’s receptors detect chitosans and can enable a more precise agricultural application according to the chitosan’s bioactivity.

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Tim Jacob Lange conducted this work at the institute of Molecular Biosciences in the working group of Prof. Dr. Maik Böhmer.

Tilman Linke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Leipzig in the year 2024 with the title:

Development of Photo-Calorespirometry, as a Novel Method to Directly Access Photosynthetic Rates and Efficiencies of cyanobacteria in real-time

The novel Photo-calorespirometry method was established and applied for the first time to cyanobacteria, using Synechocystis sp. PCC 6803 as a model, to directly quantify photosynthetic rates and efficiencies on an energy level in real-time

Photosynthesis represents a natural phenomenon performed by phototrophs, such as plants, microalgae, or cyanobacteria. Triggered by the climate crisis, an increasing focus on the generation of renewable energy carriers (e.g. hydrogen) employing phototrophs in photo-biotechnologies is emerging since they convert light energy into chemical energy. The conversion efficiency of light into chemical energy (PE) is highly dynamic and relies on a variety of alternating environmental conditions (e.g. light and substrate availability, temperature etc.), as well as internal metabolic adaptation mechanisms to balance physiological requirements regarding the fluctuating availability of light. However, the currently available techniques measure PE only indirectly, with a poor time resolution, or fail to consider the whole photosynthetic process. For that purpose, photo-calorespirometry (Photo-CR) was developed to directly measure the photosynthetically fixed energy (P_PS) as heat. Photo-CR combines calorimetry with the simultaneous monitoring of photosynthetic oxygen evolution rates (r_O2) in real-time. In this work, Photo-CR was established and validated the first time for the model cyanobacterium Synechocystis sp. PCC 6803. The experimental setup of Photo-CR has been further optimized to enhance the accuracy of the thermokinetic data, facilitate the implementation of the measurements, and minimize sources of error. A maximum fixed light energy yield over the cell dry weight of 26.4 kJ/g^_CDW, and  P^max_PS = 5.2 W/g_CDW was achieved after these adjustments. PE was analyzed at changing light intensities, resulting in a maximum of around 2.3 % and a half-maximum PE at 360 µmol_Photons/m²*s. Additionally, the outcomes indicated photo-protective mechanisms as a response to high light energy inputs. A strong correlation between calorimetry and respirometry was observed with an oxycaloric equivalent of 488.5 ± 0.3 kJ/mol_O2, providing further insights into potential side-reactions with additional energy expenditures under the consumption of oxygen (e.g. Mehler reaction, photo-respiration). Besides, the influence of distinct nitrogen sources, with different degrees of reduction, on the photosynthetic performance of Synechocystis under high and low light conditions was evaluated. Photo-CR unraveled beneficial impacts of nitrate as an additional electron sink under high light conditions, suggesting that surplus light energy can inhibit photosynthesis and that electron sinks can prevent this by receiving photosynthetically derived electrons. In conclusion, this master thesis emphasized Photo-CR as a non-invasive, holistic, quick and versatile technique to screen for the most efficient aquatic phototrophs, to elucidate optimized parameters to improve photosynthetic performances, and to expand our understanding of the underlying metabolic regulations during photosynthesis.

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Tilman Linke conducted this work at the Helmholtz Center for Environmental Research (UFZ) in the working groups of Prof. Dr. Thomas Maskow and Prof. Dr. Andreas Schmid.

Arno Krieger's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Bielefeld in the year 2024 with the title:

Mitigating transgene silencing in C. reinhardtii – Examining synergisms of transgene silencing factors through genome editing

Krieger generated a series of C. reinhardtii strains using CRISPR/Cas9 mediated genome editing, each carrying different combinations of knock-out mutations with the aim to systematically investigate the function of various silencing factors and potential synergisms between them and to develop a strain which is capable of expressing transgenes on a high level.

The unicellular microalga Chlamydomonas reinhardtii gets growing attention as a viable production host for biotechnology. Its capacity for rapid growth under phototrophic conditions, coupled with a haploid genome and well-established genetic engineering protocols, positions it as a potent and sustainable alternative to heterotrophic hosts for the biotechnological synthesis of valuable compounds. C. reinhardtii offers a great variety of biosynthetic capacities and presents several unique features for commercial exploration. Advancements in metabolic engineering empowered C. reinhardtii to successfully synthesize a diverse array of recombinant proteins and high-value molecules, like algae-based pharmaceuticals, biofuels, and terpenoids.

However, efficient transgene silencing mechanisms pose a challenge for expressing transgenes in C. reinhardtii, limiting its biotechnological potential. In C. reinhardtii, transgene silencing occurs mainly at the chromatin level. This silencing mechanism involves a variety of epigenetic modifications, including histone deacetylation, methylation and phosphorylation and DNA methylation. Although several key factors of transgene silencing were identified, the mechanism and interactions between these factors remain poorly understood.

This thesis aims to prevent transgene silencing in C. reinhardtii by genome editing, to generate strains with robust transgene expression levels. Therefore, several key factors for epigenetic transgene silencing, including SRTA, HLM4, VIG1, Mut9, and DMC5, were knocked out in different combinations, exploiting the CRISPR/Cas9 system. To investigate the transgene expression capabilities of the mutant strains, all strains were transformed with a transgenic reporter gene construct, expressing a patchoulol synthase fused to the fluorescence reporter mVenus. The transgene expression level was analysed by quantification of the fluorescence signal and the patchoulol productivity.

This study demonstrated, that CRISPR/Cas9-based strain engineering is a powerful tool to enhance transgene expression in C. reinhardtii. It was shown that epigenetic transgene silencing mechanisms can be partially prevented by disruption of the underlying key factors. Moreover, it was demonstrated that the combination of these knockouts can synergize and partially yield additive effects in the repression of transgene silencing. Especially, the combination of the SRTA, DMC5 and VIG1 knockout exhibited robust transgene expression, exceeding the patchoulol productivity of its parental strain of up to 400%. Moreover, this project accomplished a collection of 28 knockout strains, offering a foundation to decipher the mechanisms of transgene silencing. Through comparative analysis of the transgene expression capabilities of these knockout strains, hypothetical interactions between several epigenetic modifications and silencing factors could be observed.

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Arno Krieger conducted this work in the working group Algenbiotechnologie and Bioenergie of Prof. Olaf Kruse under supervision from Dr. Alexander Einhaus. 

Marie Hoensbroech's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Carl von Ossietzky-University Oldenburg in the year 2024 with the title:

What goes up, must come down? Vertical wind dispersal of epiphyte seeds in a Panamanian rainforest

The movement of plant diaspores by wind has been simulated many times before, but this is the first time that it is done for epiphytes in a rainforest.

True epiphytes commensally live on other plants, typically trees. They are unlikely to survive on the ground, but otherwise they can occur at all heights within a forest: from the base of a tree to its outermost crown. Yet, often, their distribution is clumpy or limited to a certain zone within a forest (e.g., only between 10 and 15 m above ground). Can dispersal explain these patterns? As most epiphyte species are wind-dispersed (only few are animal-dispersed), knowledge is needed of the vertical air movements. Therefore, Hoensbroech installed sonic anemometers at different heights and close to different trees in a Panamanian rainforest (see picture). The collected data was fed into a dispersal model that simulates how epiphyte seeds move within the forest. Since both strength and frequency of air movements increase with height, seeds released lower down disperse shorter distances, more often remain in the proximity of their mother plant and are more likely to land on the ground. Those released higher up are generally dispersed greater distances and are more likely to reach a different forest zone or even end up above the forest. In summary, dispersal can at least partially explain epiphyte distribution patterns, but challenges during later life stages are likely to play a role as well.

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Marie Hoensbroech conducted this work at the Institute for Biology and Environmental Sciences in the working group of Prof. Dr. Gerhard Zotz.

Robin Pelchen's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Hamburg University in the year 2024 with the title:

The optimal vertical root profile under a changing climate – a model approach

The model describes how the roots can adapt in growth and profile under changing climatic conditions. To achieve this, a new computer model was developed, whose simulation makes qualitatively realistic predictions. This allows for a better selection of specific tree species as an adaptation to climate changes.

The study investigates the effect of the vertical distribution of root biomass in trees, known as the root profile, on their productivity under various environmental conditions. Using a newly developed mechanistic computer model of water transport and CO₂ fixation in trees, many different root profiles were simulated, and those that optimize productivity and thus growth under given environmental conditions were identified. This allowed for testing the hypothesis that trees tend to develop an optimal root profile adapted to the environment through natural selection.
The model was able to predict qualitatively realistic root profiles. It confirmed the assumption that trees align their optimal root profile with the relative maximum of soil moisture (influenced by soil properties and rainfall patterns). However, a strong effect of temperature on the optimal root profile was not found.
In recent years, the negative impacts of drought related to climate change on forests, including in Germany, have become evident. However, it remains largely unclear which types of trees will be viable in the long term in the future. The modeling can provide valuable insights into which root profiles, and thus tree types, will be optimally adapted to future climate conditions and have better chances of survival.

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Robin Pelchen conducted this work at the IPM institute, Ecological modeling in the working group of Prof. Dr. Philipp Porada.

To master thesis: https://www.biologie.uni-hamburg.de/forschung/oekologie-biologische-ressourcen/oekmodel/abschlussarbeiten/master-thesis-by-robin-pelchen.pdf

Vincent Kaltenbach's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Universität Münster in the year 2024 with the title:

Investigation of the oxidosqualene cyclase family from Arabidopsis thaliana

Candidate oxidosqualene cyclases from Arabidopsis thaliana are consistently localized at lipid droplets, which may represent a promising target for engineering terpene synthesis and storage.

Plant terpenes not only cover essential native functions for plant survival but also have great potential for technical applications. Their complex cyclization is carried out by the oxidosqualene cyclase (OSC) family from one structural precursor. In a multistep approach, the structural properties of the respective candidates were first bioinformatically analyzed. Subsequently, subcellular localization studies and transient expression for production were performed. All OSCs shared a prominent superficial hydrophobic region and showed lipid droplet localization as confirmed by microscopy. Transient (co)-expression with upstream bottleneck enzymes revealed substantial amounts of triterpene products. Greater knowledge of their localization and production patterns may contribute to further biotechnological approaches aimed at increasing yields.

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Vincent Kaltenbach conducted this work at the Institute of Plant Biology and Biotechnology in the working group of Prof. Dr. Till Ischebeck.

Carolin Goldhardt's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Martin-Luther-Universität Halle-Wittenberg in the year 2024 with the title:

Study on the mitochondrial localisation of the protein mTERF21 and on RNAs associated with mTERF21 in vivo in Arabidopsis thaliana

Using GFP tagging of the RNA-binding protein mTERF21, this work shows the association of the mitochondrial mTERF21 protein with multiple mRNAs and its presence in distinct foci within mitochondria.

Plant mitochondria are known for their highly complex RNA metabolism, involving hundreds of nucleus-encoded proteins that contribute to mitochondrial gene expression. Many of these proteins are part of the mitochondrial transcription termination factor (mTERF) family, whose members are also found in animal mitochondria, but which substantially expanded in land plants. For very few plant mTERFs has their exact molecular function been identified. While some were reported to indeed act as transcription termination factors, others were found to function in the splicing of organellar mRNAs.

To gain insight into the role of the mTERF family protein mTERF21, which in Arabidopsis is essential, an Arabidopsis line expressing a pmTERF21::mTERF21-GFP construct in an mterf21 loss-of-function background was used for localization studies and for RNA co-immunoprecipitation (RIP) experiments. These RIP experiments found several mitochondrial RNAs to associate with mTERF21 in vivo. Analyses of mTERF21-GFP localization by confocal microscopy detected GFP accumulation in distinct foci within mitochondria. This distribution of GFP was clearly different from that seen in a control line expressing GFP fused to a mitochondrial transit peptide. Accordingly, mitochondrial RNA metabolism involving mTERF21 might be restricted to a specific mitochondrial sub-compartment. To pave the way for further investigations of this hypothesis, a collection of Arabidopsis lines expressing fusions of different RNA- and DNA-binding proteins to fluorescent proteins has been created.

The thesis was supervised by Theresa Schoeller and Kristina Kühn in a project associated with RTG2498; the mTERF21-GFP line was provided by Minsoo Kim and Elizabeth Vierling (UMass Amherst).

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Carolin Goldhardt conducted this work at the institute of biology, department of Cell Physiology in the working group of Prof. Dr. Kristina Kühn.

Anna Wurster's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Kassel University in the year 2025 with the title:

Pilot study on the resource use of wild bees on grassland areas of the Hessian State Domain Frankenhausen using a novel collection method and DNA metabarcoding

The pilot study shows that even small wild bee species can be successfully analyzed by means of a minimally invasive collection method and pollen metabarcoding and that these are useful for studies on biodiversity in agricultural landscapes.

Around half of all wild bee species in Germany are critically endangered or even extinct; there has been a sharp decline in wild bee diversity, particularly in agricultural ecosystems, with the specialization of many species in certain nesting and feeding sites making them particularly susceptible to changes in their environment. Understanding the diversity and food spectra of individual wild bee species in agroecosystems is essential to halt this decline. For this purpose, this master's thesis investigated the occurrence of wild bees and the respective resource utilization of individual bees on two grassland areas of the Hessian state domain Frankenhausen (Hesse/Germany), using a minimally invasive collection method, pollen metabarcoding and taking into account different inspection strategies and collection times. Over 100 different plant traces were detected and identified on a total of 40 different wild bee species and food webs were created for individual specimens. Differences were found both in the abundance of the animals and in their respective resource use in dependence on the chosen inspection strategy and time of day. The results of this pilot study clearly show that different collection strategies do have an influence on the obtained results and thus make it possible to make recommendations for optimized follow-up studies, which can be used to record wild bee diversity even more efficiently in the future.

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Anna Wurster conducted this work at the institute for biology in the botany working group of Prof. Dr. Birgit Gemeinholzer.

In the year 2025 DBG's representatives at the participating universities evaluated master theses in plant sciences. The following persons received the award so far (in alphabetical order):

Gesa Birkenbach (Leibniz Universität Hannover)
Machine Learning Identification of Triterpene-Modifying Cytochrome P450 Monooxygenases

Johanna Söntgerath (University of Freiburg)
Analysis and epigenetic editing of the H3K27me3 trimethylation pattern of flooding memory genes in Arabidopis thaliana

Anna Wurster (Universität Kassel)
Pilot study on the resource use of wild bees on grassland areas of the Hessian State Domain Frankenhausen using a novel collection method and DNA metabarcoding

Johanna Söntgerath's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Freiburg University in the year 2025 with the title:

Analysis and epigenetic editing of the H3K27me3 trimethylation pattern of flooding memory genes in Arabidopis thaliana

Plants can form an epigenetic stress memory, and the modification of the epigenetic profile of the memory genes enables the development of more resilient plants.

Severely changing environmental conditions, such as floods, can be lethal for plants. As an adaptive mechanism to cope with abiotic stress, plants exposed to recurring floods may form a so-called epigenetic memory. Stress memory causes gene expression alterations, which leads to an improved stress performance and a higher survival rate. Johanna Söntgerath studied the epigenetic pattern at flooding memory genes in Arabidopsis thaliana and identified a memory gene which is associated with the induction of cell death. The expression of this memory gene is downregulated during the second compared to the first flooding event. Epigenetically, this gene is regulated via, among others, a histone methylation (H3K27me3). Targeted addition or removal of this epigenetic mark through the CRISPR-based method epigenome editing may impact the plant stress resilience. Based on this approach, Söntgerath produced gene constructs to modulate the H3K27me3 profile at the cell death gene. Prospective experiments will investigate the potential of these constructs in modulating plant stress resilience. Understanding the flooding stress responses and adaptations of Arabidopsis enables the development of more resilient crops, including closely related Brassicaceae and more distant families such as Solanaceae. Due to ongoing climate change and the increased frequency and severity of flooding events, this could contribute to securing food availability.

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Johanna Söntgerath conducted this work at the institute of Biology at the University of Freiburg in the working group of Dr. Sjon Hartman.

Gesa Birkenbach's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Gottfried Wilhelm Leibniz Universität Hannover in the year 2025 with the title:

Machine Learning Identification of Triterpene-Modifying Cytochrome P450 Monooxygenases

How machine learning can be used to facilitate the functional characterization of plant plant cytochrome P450 (CYP) enzymes by making predictions on the enzymes‘ substrate group.

Cytochrome P450 enzymes (CYPs) form one of the largest enzyme superfamilies with functions in many different metabolic pathways. They are especially important in the biosynthesis of plant triterpenoids, a large group of structurally and functionally diverse defense compounds. However, the identification of CYPs with activities in a specific metabolic pathway is often hindered by the multitude of CYP enzymes in the plant organism. To facilitate the selection of relevant CYP enzymes, a machine learning model was trained in this master’s thesis to predict whether a cytochrome P450 enzyme might be involved in the biosynthesis of plant triterpenoids based on the enzyme’s protein sequence. To understand the working mechanism behind the model, it was investigated which sequence properties were relevant for the model’s decision-making process. By applying the model to the protein sequences of a test plant, predictions could be made for CYP enzymes that might be involved in yet unknown metabolic pathways and could thus be helpful in their elucidation. An analysis of incorrect predictions furthermore provided valuable insights into the model’s weaknesses, which will guide future improvements to the model. The master’s thesis demonstrates the potential of interdisciplinary research approaches and the possible benefits of artificial intelligence for the plant sciences.

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Gesa Birkenbach conducted this work at the Institute of Cell Biology and Biophysics and at the Institute of Botany in the working groups of Prof. Sophia Rudorf and Prof. Jakob Franke.