Botany Seminars

Program summer semester 2026

When?

• Wednesdays at 1:15pm (during the semester, unless specified otherwise).

Where?

• Room 109, first floor. Botanical Institute, Menzinger Str. 67, 80638 München.

Overview

15 April 2026

TBA

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April 22 2026

Dr. Garima Singh, Department of Biology, University of Padova, Padua, Italy.

Why Fungi Matter: Linking Diversity, Evolution, and Chemical Innovation

Fungi occupy an unusually broad ecological and cultural spectrum. They are integral components of the ecosystem, and our lives, essential to food and fermentation. They are prolific producers of bioactive compounds, and, at times, serious agents of disease in plants and humans. This diversity of roles is not accidental but is deeply rooted in the extraordinary evolutionary and chemical diversity of the fungal kingdom.
A central feature of fungal diversity is the evolution of secondary metabolism and related pathways. The genetic machinery underlying secondary metabolism has evolved in highly dynamic and lineage-specific ways across the fungal tree of life, shaped by ecological pressures and lifestyle transitions. This is reflected in the selective gain, loss, and diversification of biosynthetic gene clusters across different fungal groups. As a result, fungi display a magnitude of diversity in their capacity for biotic and abiotic inetreactions, while also forming the molecular basis of many compounds of pharmaceutical and industrial relevance.
The evolution of secondary metabolism is therefore of twofold interest: it provides insight into its evolutionary consequences and diversification, while also highlighting the taxa with potential industrial applications. However, understanding how this chemical and genomic diversity is distributed across fungal lineages, and identifying the most promising resources, remains a major challenge.
In this talk, I will discuss how comparative genomics and computational approaches, integrated with the biology of secondary metabolism, can be used to dissect the ecological and evolutionary drivers of fungal chemical diversity. By using integrative omics to explore biosynthetic potential and its link to fungal ecology and evolution, we can uncover how chemical diversity arises and identify ecologically and industrially relevant metabolic pathways.

Host: PD Dr. Andreas Beck

29 April 2026

Dr. Marion Müller, TUM School of Life Sciences, Chair of Phytopathology, TUM, Munich, Germany.

Title and abstract: TBA

Host: Dr. Anže Žerdoner Čalasan

06 May 2026

TBA

13 May 2026

Dr. Michael Burkart, Universität Potsdam, Germany.

Title and abstract: TBA

Host: Dr. Thibad Messerschmid

20 May 2026

Prof. Dr. Veronica G. Maurino, Universität Bonn, Germany.

Title and abstract: TBA

Host: Dr. Renata Callegari Ferrari

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27 May 2026

Prof. Dr. Richard Beckett, School of Life Sciences, University of KwaZulu Natal, Pietermaritzburg, South Africa.

Photoprotection in lichens: adaptations of photobionts to high light

This talk will review the ways that lichens acclimate and adapt to their light environment, in particular in response to high light. While light is essential for photosynthesis, lichens often absorb more light than their photobionts can use for carbon fixation, and as a result potentially harmful reactive oxygen species (ROS) can be formed. However, lichens are poikilohydric organisms and spend much of their lives in the desiccated state. Light will only drive or inhibit photosynthesis when lichens are hydrated. Therefore, the “light environment” of a lichen at a particular moment is determined by both the photosynthetically active radiation (PAR) and also the thallus water status. Lichens growing in shaded microhabitats e.g. on the trunks of woodland trees experience considerable short term (seconds to minutes) changes in light levels due to gaps in the canopy and diurnal variations in the angle of sunlight, and movements of tree branches. The relatively brief periods that lichens are exposed to high light levels are known as “sunflecks”. By contrast, lichens growing in exposed microhabitats may receive photoinhibitory levels of light typically early in the morning, before they dry out. While the mechanisms used by lichens from varying microhabitats may differ, it seems likely that a common set of core mechanisms exists. Tolerance can occur by “avoidance” strategies that reduce ROS formation, via synthesizing light screening pigments or by thermally dissipating or “quenching” the excess light energy absorbed. “True tolerance” strategies involve scavenging ROS once formed or by repairing ROS-induced damage. These mechanisms will be reviewed, with an emphasis on recent findings on first the role of melanins as light screening pigments and second on mechanisms of thermal dissipation. It is becoming apparent that thermal quenching can be increased by stresses other than light, probably because any stress that damages the photosynthetic apparatus will further increase light-induced ROS formation. Results will be presented showing that treatment with moderate light in combination with stresses such as chilling, heat and heavy metals can increase quenching more than light alone. The lecture will conclude with perspectives for future research.

Host: Prof. Dr. Silke Werth

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03 June 2026

Prof. Dr. Caroline Müller, Chemical Ecology, Universität Bielefeld, Bielefield, Germany.

Impacts of plant chemodiversity on the environment and vice versa

Chemical diversity, or chemodiversity, is a fascinating trait that is attracting increasing attention due to its diverse ecological functions and intriguing evolution. The variation in chemical phenotypes of organisms plays a fundamental role in shaping species interactions, and can be studied using different metabolomics approaches in combination with laboratory and field bioassays. Inter- and intraspecific chemodiversity of plants influences the specific outcome of plant-herbivore, plant-pollinator and also plant-microbe interactions. Moreover, not only the individual plant chemodiversity matters, but plant neighbourhood chemodiversity is likewise very important for driving antagonists and mutualists and thus impacting plant fitness, as I will demonstrate using our data on the highly chemo-diverse, aromatic plant species Tanacetum vulgare. In turn, plant chemodiversity is modulated by abiotic and biotic challenges acting alone and in combination on the plant. Chemodiversity at various levels also influences niche realisation processes, such as niche choice, conformance and construction of individuals. I will highlight several examples of the intriguing functions of plant chemodiversity.

Host: Anna Pasinato

10 June 2026

Dr. Thomas L.P. Couvreur, Institut de Recherche pour le Développement (IRD), France.

Title and abstract: TBA

Host: Dr. Luo Chen

17 June 2026

Dr. Sebastian Mortimer, Systematics, Biodiversity, and Evolution of Plants, LMU Munich, Munich, Germany.

Title and abstract: TBA

Host: Prof. Dr. Gudrun Kadereit

24 June 2026

Dr. Maria-Anna Vasile, Botanischer Garten und Botanisches Museum Berlin, Berlin, Germany.

Title and abstract: TBA

Host: Dr. Diego F. Morales Briones

01 July 2026

TBA

08 July 2026

No Botany Seminar

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15 July 2026

Prof. Dr. Silke Robatzek, LMU Munich Biocenter, Munich, Germany.

Plant relationships with microbes: Immunity, pathogens, and the microbiome

Plants have an innate immune system to defend against pathogens, yet these defences are often overcome, leading to severe diseases and major economic losses. My primary research interest is to learn what determines the outcome of infections. In my group, we address the following questions: How do plants protect themselves against infection, and how do pathogens achieve infection? We focus on the key molecular and cellular mechanisms underlying infection control, and on how the microbiome and environmental cues shape immune responses and disease progression. Recently, we have begun exploring plant immune responses to Xylella fastidiosa, an insect-transmitted, xylem-limited bacterial pathogen and a high-priority pest in Europe. X. fastidiosa causes devastating diseases, including Pierce’s Disease in grapevines and Olive Quick Decline Syndrome, which has led to the death of millions of olive trees. In this seminar, I will present our recent findings and ongoing work on plant responses to X. fastidiosa, including results from experimental model plants and insights into the immune capacity of different olive cultivars.

Link to Robatzek lab

Host: Prof. Dr. Gudrun Kadereit

Winter Semester 2025-2026

Abstracts

15 October 2025

Prof. Dr. Christoph Oberprieler, Universität Regensburg, Regensburg, Germany.

Wettstein goes Carrara - Integrative species delimitation in hybridising plant groups

Host: Prof. Dr. Gudun Kadereit

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22 October 2025

Dr. Emy Yue Hu, Systematics, Biodiversity and Evolution of Plants, LMU Munich, Munich, Germany.

Network Biology Across Kingdoms: From Human Systems to Plant Ecology and Evolution

Network biology offers a powerful framework for modeling the complex, multi-layered interactions that underlie biological systems. By integrating concepts from graph theory, machine learning, and multi-omic data analysis, it enables us to move beyond isolated molecular signals toward a systems-level understanding of life. In this talk, I will introduce computational frameworks for integrating heterogeneous omics data and embedding biological networks for efficient analysis and link prediction—tools originally developed to uncover mechanisms of human disease and guide drug repurposing. I will then demonstrate how these approaches can be extended to plant systems, where differential network analysis can provide new insights into how regulatory interactions shift across environments. Looking forward, I aim to explore with you the untapped potential of network biology in plant systems to reveal new dimensions of plant ecology, adaptation, and evolution.

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29 October 2025

PD. Dr. Andreas Fleischmann, SNSB-BSM, Botanische Staatssammlung München, Munich, Germany.

News from the world of carnivorous plants: pollination, prey, phylogenies & photosynthesis

The ca. 860 known species of carnivorous plants cover a lot of fascinating aspects that go beyond their insectivorous nature. The talk will cover the latest research on insect pollination of carnivorous plants, avoidance of pollinator-prey conflicts, prey attraction in sticky carnivorous plants, especially in sundews (Drosera, Droseraceae), insect kleptoparasitism (prey theft from carnivorous plants), prey-driven sympatric speciation, radiation and biogeography of "modern" Drosera-lineages out of Australia and a sneak-preview on CAM photosynthesis in dry tolerant Mexican Pinguicula (Lentibulariaceae).

12 November 2025

Prof. Dr. emer. Hebert Hurka, Universität Osnabrück, Osnabrück, Germany.

Florogenesis of the Eurasian steppe region

The Eurasian steppe belt is the largest steppe region in the world and stretches from the Hungarian basin and Danube delta in the west to the Amur in the east. It ranges from 800 to 1000 km from North to South, and about 8000 km from West to East. In contrast with the knowledge about floristic composition of the present steppe area is a lack of studies on the evolutionary and biogeographical history of Eurasian steppe plants. To understand the florogenesis of the present steppe flora we have to consider the climate/landscape history of the Eurasian steppe regions. Only limited conclusions about ancient areas can be drawn from present-day biogeography. Since modern zonal steppe formed at different times and in different geographical regions, we expect colonization from different source areas and at different times. We hypothesize that molecular signals in steppe plants reflect the florogenetic dynamics and allow finer resolution of the history of the steppe flora. Dated molecular phylogenies, haplotype networks and ancient area reconstructions appear as proper tools to achieve our aims. We explore the geographic structure of genetic diversity within species or species groups. Based on several examples, colonization histories and migration times and routes are traced and analyzed for common patterns.

Host: Prof. Dr. Gudun Kadereit

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19 November 2025

Dr. Christopher Lambert, Helmholtz-Zentrum f. Infektionsforschung GmbH, Braunschweig, Germany.

Improving the systematics of Xylariales through a polyphasic approach

Fungi of the order Xylariales (Ascomycota) are worldwide distributed and harbor complex lifecycles in which they appear as saprobes, phytopathogens or endophytes and form often carbonized conspicuous teleomorphs, which have traditionally been utilized for their systematic classification. This monolithic concept is constantly being challenged by ongoing molecular phylogenetic studies, which repeatedly reveal that anamorph morphology and production of secondary metabolites – chemical compounds dispensable for survival, but thought to improve fitness in natural habitats – serve as more robust predictors of generic affinities. Nowadays analysis of a broad spectrum of assessable phenotypic characters in tandem with each other in polyphasic studies is considered the gold standard to settle their relationships. An increasing number of reports also provides full genomes, leaving the systematics of the Xylariales on the verge of revolution. Epitypification campaigns pursued in the interim build a sound fundament for this endeavor, as many type specimen are lost or cultures for in-depth characterization are lacking. This sometimes unravels unexpected taxonomic affinities of surveyed taxa. Moreover, the study of chemotaxonomic markers, such as pigments, as well as the chemical survey of understudied or novel species continually serve as sources for novel chemistry. This fact can, for example, be exploited for drug discovery screening campaigns, in which these compounds often show promising bioactivity. This talk is dedicated to the report of recent surveys of fungal biodiversity combining the search for novel chemistry with the description and characterization of fungi of the Xylariales, with special emphasis on the taxonomy of the Xylariaceae, Hypoxylaceae and allied families. Moreover, new and previously described secondary metabolites, as well as their antimicrobial and cytotoxic properties will be discussed briefly as well as their related potential for future applications.

Host: Dr. Anže Žerdoner Čalasan

3 December 2025

Dr. Norico Yamada, Principal Investigator; CNRS, Roscoff Marine Station, Roscoff, France.

How to upgrade stolen organelles into permanent plastids: A comparative transcriptomic perspective

Plastid (Chloroplast) origins remain one of the most striking examples of endosymbiosis, yet most extant photosynthetic organisms represent the evolutionary endpoint. In contrast, "dinotom" dinoflagellates retain diatom-derived tertiary plastids spanning a continuum of integration states: from temporary kleptoplastidy to permanently retained, transcriptionally active endosymbionts. This living evolutionary spectrum makes dinotoms uniquely suited to experimentally dissect how prey microalgae transition into permanent plastids.
In this talk, I will present new comparative transcriptomic data (Yamada et al. 2025, PNAS), the first cross-species analysis across three integration states in dinotoms. These results reveal striking transcriptional autonomy of symbiont nuclei, while expression of diatom genes appears domesticated to support photosynthesis. We also find evidence of early genomic modification and emerging host control over nutrient exchange. These findings raise key questions: is the degeneration of the diatom nucleus underway in these endosymbionts, and how do controls of metabolic exchange facilitate progression from kleptoplastidy to permanence. Building on this foundation, I will outline future projects combining cell imaging, bioinformatics, genetic transformation, and proteomics to illuminate these processes.

Host: Prof. Dr. Marc Gottschling

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10 December 2025

Dr. Jan Tebben, Alfred Wegener Institut, Bremerhaven, Germany.

Polyketide ichthyotoxins in a changing world: ecology, history, and the chemistry of fish kills

Fish kills caused by toxic microalgae are becoming an increasingly visible threat as marine aquaculture expands and extreme climate events increase in frequency. Recent events, such as the Prymnesium parvum bloom in the Oder/Odra River in 2022, large Chrysochromulina leadbeateri blooms in Norway in 2019 and 2025, and the recent Karenia cristata bloom in South Australia, illustrate the impact of these events on public health as well as the substantial economic losses in fisheries, aquaculture, and tourism. Yet for many of these blooms, we still know surprisingly little about their underlying causes, the interactions between toxin producers and co-occurring organisms, or the mechanisms by which the toxins exert their effects.
This talk will focus on the chemical ecology of large polyketide ichthyotoxins and their producers, such as P. parvum (prymnesins) and C. leadbeateri (leadbeaterins). I will present an overview of recent bloom events and their commonalities, recent work on isolating and measuring fish-killing toxins in situ, and initial toxicity data that reveal their biological effects on fish, cell lines, and co-occurring organisms. Finally, I will combine these mechanistic insights with historical records and monitoring data to ask whether these toxin-producing species and their blooms represent a genuinely new phenomenon, or a long-standing, climate- and human-activated hazard that we are only now beginning to recognize and quantify.

Host: PD Dr. Andreas Beck

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11 December 2025 at 9:00 am (extra seminar)

Dr. Charlotte Goeyers, Protistology & Aquatic Ecology, Dept. of Biology, Ghent University, Belgium.

Unlocking the full potential of moss-associated diatoms to reconstruct local climate change in alpine and arctic regions

The planet is warming at an accelerating pace, and the consequences—melting ice caps, rising sea levels, and shifting ecosystems—are becoming more tangible every day. While temperatures are rising twice as fast compared to the global average in alpine regions, Arctic warming is amplified up to four times. However, since meteorological data is extremely scarce before the 1950s, it is challenging to put climate change into a long-term perspective. In this talk, I will discuss how moss diatoms can contribute to a better understanding of past, current, and future climate change in alpine-arctic regions. Given their extreme sensitivity to changes in their environment, diatoms are excellent as bio-indicators. Due to their glass cell walls, diatoms are remarkably resistant to degradation over time, enabling their preservation in ice and sediment cores or even herbarium collections. As many herbariums contain historic moss collections sampled after the end of the Little Ice Age in alpine-arctic regions, this offers unique opportunities to reconstruct how their diatom communities responded to climatic shifts over time. I will furthermore demonstrate how both morphology and metabarcoding on modern and historic herbarium samples can be applied to reconstruct past climate regimes, facilitating future conservation efforts in these sensitive ecosystems.

Host: PD Dr. Andreas Beck

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17 December 2025

Dr. Christina Steidele, TUM, Munich, Germany.

Regulatory networks driving barley’s response to Fusarium head blight in complex environments

Fusarium head blight (FHB) represents a major threat to barley and other small-grain cereals, causing substantial yield and quality losses. The disease is primarily induced by fungi within the Fusarium species complex, which can produce harmful mycotoxins. Although transcriptional responses to FHB have been characterized, the regulatory mechanisms underlying these responses—particularly under combined biotic and abiotic stresses such as drought—remain poorly understood.
We employed network inference approaches combined with the analysis of genomic resources to identify stress-responsive genes and candidate transcription factors (TFs) that may orchestrate these responses. Furthermore, we integrated multi-omics datasets, including transcriptomic, proteomic, and metabolomic profiles, to uncover a coordinated upregulation of aromatic amino acid-derived secondary metabolism as a consistent defense strategy in barley against FHB. This metabolic reprogramming involves the accumulation of tryptophan-derived metabolites (e.g., tryptamine, serotonin) and barley-specific hydroxycinnamylamides (hordatines).
Our gene regulatory network analyses predict TFs with strong influence over pathways associated with aromatic amino acid-derived secondary metabolism. By targeting key TFs and generating stable barley mutants with altered metabolic profiles, we aim to elucidate the functional contribution of these pathways to basal defense mechanisms against FHB. This integrative approach provides novel insights into the regulatory architecture of barley’s response to FHB and highlights potential targets for improving disease resistance under complex stress conditions.

Host: Prof. Dr. Silke Werth

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14 January 2026 at 11:15

Dr. Julius Jeiter, Dresden University of Technology, Dresden, Germany.

Integrating comparative morphology and development into evolutionary research

For many years, comparative morphology was the primary source of information for systematic studies. However, since the early 1990s, molecular phylogenetics and phylogenomics have revolutionised plant systematics. Technological advances and progress in our understanding of evolutionary processes have resulted in a well-resolved and stable system of plants, particularly for angiosperms. The current system of angiosperms is primarily, if not entirely, based on molecular phylogenetics.
This well-resolved, stable system provides an ideal foundation for understanding morphological and anatomical evolution. However, it is imperative for this task that morphological and anatomical characters are clearly delineated and defined. It is important to note that the 'mature' state of characters, when considered in isolation from their development, has the potential to be misleading. This is due to the fact that it has the potential to obscure significant aspects that are necessary for a comprehensive definition. It is therefore imperative to acknowledge the significance of development in character definition when formulating evolutionary hypotheses about character evolution in a molecular phylogenetic context.
I argue that, when combined with the latest technologies and a developmental approach, comparative morphology is an important modern scientific discipline that is essential for improving our understanding of the evolution of angiosperms and many other taxa.
Here, I present guidelines for conducting comparative morphological, anatomical and developmental studies. Examples from my current research show how this approach is being used. I want to encourage students and early-career scientists to adopt a comparative morphological approach in their plant systematics research.

Host: Dr. Agnes Scheunert

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21 January 2026

Dr. Clara Groot Crego, Austrian Research Centre for Forests (BFW), Vienna, Austria.

The role of introgression in shaping ecological diversity and local adaptation: insights from Tillandsia and in European white oaks

Hybridization is a key evolutionary process that can foster ecological transitions and adaptation through the exchange of genetic variation between species. Recent research has revealed that hybridization between radiating lineages can result in adaptive introgression and may enhance rapid diversification. In this talk, I outline two research projects that aim at better understanding the role of hybridization in ecological diversification in two plant lineages: Tillandsia and white oaks (Quercus spp.).
The bromeliad subgenus Tillandsia represents an exemplary case of evolutionary radiation, exhibiting multiple key innovation traits linked to elevated diversification rates, including CAM photosynthesis, tank formation, distinct pollination syndromes and growth on different substrates. We make use of a targeted sequencing approach with a Bromeliad-specific bait set of over 1,700 genes including hundreds of known genes involved in key innovation traits to investigate the evolutionary history and prevalence of reticulate evolution in 35 Tillandsia species encompassing the ecological diversity of the radiation. We found pervasive gene flow across the subgenus, and detected two major ancestral hybridisation events between subclades that may have resulted in adaptive introgression. Gene flow signatures are more common in species pairs that share a key innovation trait. Using the McDonal-Kreitmann test, we detected convergent positive selection in CAM-related genes among subclades, with ongoing analyses testing for adaptive introgression between lineages in these candidate genes. Our results point to a potential widespread role of introgression in shaping and maintaining ecological diversity in the subgenus Tillandsia.
The white oak species complex (Quercus sect. Quercus) comprises some of the most widespread and ecologically important tree species in Europe. Nevertheless, its taxonomy and evolutionary history—particularly in Southeastern Europe, where several potentially drought-tolerant subspecies occur—remain insufficiently resolved. We hypothesize that climate adaptation and adaptive introgression during the divergence of white oak lineages play a major role in the diversification of the group. The HybOakAdapt project integrates whole-genome resequencing and leaf-morphology data from 1,205 trees spanning Central and Southeastern Europe, Türkiye, and Georgia, including both pure and mixed stands. To investigate the role of gene flow in driving local adaptation, we aim to identify candidate loci for climate adaptation through genotype-environment association studies, and test whether they are involved in hybridization. Early analyses point at substantial introgression between lineages, including both ancient and recent events. This study provides a robust framework for understanding local adaptation and the maintenance of species boundaries in a strongly hybridizing system, with far-reaching implications for taxonomy, conservation, and the management of mixed forests under climate change.

Host: Dr. Thibaud Messerschmid

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28 January 2026

Prof. Dr. Norman J. Wickett, Universität Wien, Vienna, Austria.

Phylogenomic approaches to understanding species radiations from deep to shallow phylogenetic scales

A phylogeny provides the foundation for comparative evolutionary biology, particularly for understanding patterns of current and past diversity. Limitations in data availability have long been overcome thanks to high-throughput sequencing technologies, but the application of this huge volumes of data to phylogenetic questions has led to a better understanding of the relationship between phylogenetic signal and the history of speciation. In this seminar, I will discuss the application of target enrichment, transcriptomes, and whole-genome sequences to studying species radiations, spanning both deep (the evolution of mosses) and shallow (species complexes within Oenothera) scales.

Host: Dr. Diego F. Morales-Briones

4 February 2026

Prof. Dr. Peter Schönswetter, Department of Botany, University of Innsbruck, Innsbruck, Austria.

Patterns of polyploid distribution in the Eastern Alps based on an unprecedentedly large dataset

Polyploidy, the possession of more than two chromosome sets, is a key feature of plant biodiversity. A recent comprehensive analysis of global chromosome count data has shown that the frequency of polyploids increases with latitude. Much less is known about ploidy variation and distribution in mountain areas. In temperate mountain ranges, the frequency of polyploids may rise towards high-elevation habitats (due to, for instance, their higher stress tolerance) and with increasing distance from glacial refugia (due to better colonizing abilities). Employing flow cytometry, we established
ploidy levels of a flora-wide sampling of almost 45,000 individuals of angiosperms from 101 elevational transects in the Eastern Alps. Unexpectedly, the highest frequency of polyploids was found in the lowest elevation belt and diploids predominate with increasing altitude. On the other hand, polyploids increase with increasing distance from Pleistocene refugia, but this effect is relatively weak. This project does not only represent an unprecedentedly broad empirical test at the landscape level of the long-standing hypothesis of a positive association between genome duplication and spatio-temporal environmental variation. It also yielded much basic ploidy level information, which forms a solid base for upcoming taxonomic studies targeting heteroploid species. Finally, our data also clearly pointed at the existence of species new to science.

Host: Dr. Simon Pfanzelt

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18 February 2026

Prof. Dr. Joachim W. Kadereit, Systematics, Biodiversity, and Evolution of Plants, LMU Munich, Munich, Germany.

Phylogeny, classification and the evolution of characters

Host: Dr. Andreas Gröger

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4 March 2026 (extra seminar)

Dr. José Miguel Valderrama Martín, Institute of Plant Biochemistry Heinrich Heine University Düsseldorf/CEPLAS, Düsseldorf, Germany.

Towards C4 photosynthesis: ecology and leaf anatomy of the C3-C4 intermediate species Moricandia arvensis

Certain plant species have been identified as natural intermediates in the evolutionary transition from C3 to C4 photosynthesis, as they exhibit CO2 compensation points that fall between those observed in typical C3 and C4 plants and C4-like leaf anatomical features. Consequently, the study of C3–C4 intermediates offers a unique opportunity to deepen our understanding of the evolutionary trajectories of photosynthetic pathways, but also for paving the way to more resilient plants in the context of climate change.
Using the Brassicaceae family—which encompasses five independent evolutionary origins of C3–C4 intermediate photosynthesis—we investigated the ecological performance of these species to identify potential adaptive advantages associated with this photosynthetic type. In addition, anatomical analyses of the leaves of Moricandia arvensis (C3-C4) and Moricandia moricandioides (C3) revealed distinctive structural features linked to this intermediate anatomy, shedding light on how these traits may contribute to the functioning of C3–C4 photosynthesis.

Host: Dr. Renata Callegari Ferrari

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17 March 2026 (Tuesday, extra seminar)

Kate Samra, New York Botanical Garden, New York, U.S.A.

Leaf domatia: an understudied but integral player in global plant-invertebrate ecology

Plant and invertebrate populations are declining rapidly. Due to the many and complex ecological relationships between plants and invertebrates (i.e., pollination, dispersal, and herbivory), their declines are often interconnected. Leaf domatia, small structures that house invertebrates, represent an understudied yet common, plant-invertebrate relationship. The family Melastomaceae includes hundreds of species with leaf domatia and exhibits an impressive morphological diversity of these domatia. However, the lack of a family-wide survey of leaf domatia, as well as a universal morphological classification of domatia, has limited meaningful study of their ecology and evolution. Almost nothing is known about which invertebrates inhabit leaf domatia, how the plants may benefit from the presence of invertebrates, or how tightly specialized these relationships are. In this talk, I illustrate the process of classifying domatia diversity in Melastomaceae, discuss the limitations of such a classification, outline plans for further research on these unique structures, and summarize why this is relevant to the conservation of both plants and invertebrates.

Host: Dr. Luo Chen

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25 March 2026 at 11:15 in the Big Lecture Hall (extra seminar)

Prof. Dr. Susanne S. Renner, Washington University, Department of Biology, Saint Louis (Missouri), U.S.A.

Understanding & solving gene tree conflicts in the angiosperms

My talk will cover three processes that contribute to gene tree/species tree discrepancies, namely (i) paralogy/orthology as drivers of evolutionary novelty and a major technical headache as long as we insist on dichotomous species trees, (ii) hybridization, and (iii) budding speciation, the latter inevitably resulting in polytomies in phylogenetic trees. The message is that we need to move away from dichotomous trees as the only way to visualize phylogenetic hypotheses. The talk is partly based on results from Renner, S. S., G. Grimm, and D. D. Sokoloff. 2026. Surviving ancestors, hard polytomies, and seed plant evolution. Evolution, in press.

Host: Prof. Dr. Marc Gottschling

Summer Semester 2025

Abstracts

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23 April 2025

Prof. Dr. Michael Matschiner, Chair of Systematic Zoology at LMU München and Director of the Bavarian State Collection for Zoology (ZSM), Munich, Germany.

Divergence-time estimation for phylogenomic analyses

Divergence-time estimation of phylogenetic divergences can allow insights into the causes of those divergence events; however, accurate age estimates depend on careful implementation of calibration constraints and the avoidance of biases that could influence mislead the interpretation. In this talk, I will present the application of Bayesian fossil-based divergence-time estimation to a number of model systems, including cichlid fishes radiating in the East African Lake Tanganyika, catfishes separated by the Isthmus of Panama, and eelgrass of the Pacific and Atlantic Oceans.

Host: Dr. Diego F. Morales-Briones

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30 April 2025

M.Sc. Cathrin Manz, Goethe University Frankfurt, Germany.

Diversity and ecology of ectomycorrhizal Russula species (Basidiomycota, Fungi) in the tropics

Species of the genus Russula are key components of ectomycorrhizal ecosystems worldwide, yet they remain largely understudied in tropical regions. This talk explores the vibrant biodiversity and ecology of Russula species in the tropics, particularly in Central America and West Africa. We will trace old, forgotten taxa and embark on an exciting journey of discovery, uncovering numerous new species through the analysis of both historical herbarium specimens and recently collected material. Additionally, we will discuss functional morphological adaptations of fruiting bodies across different habitat types, as well as past and present evolutionary processes in the Isthmus of Panama.

Host: Dr. Anže Žerdoner Čalasan

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07 May 2025

Prof. Dr. Alexander Schmidt, University of Göttingen, Germany.

Reconstruction of amber forests using plants, lichens and fungi

The reconstruction of amber forests challenged scientists during the last decades, as interpretations of numerous arthropod inclusions led to conflicting assumptions about the structure and habitat types of these forests and prevailing climates. Using Eocene Baltic amber as a case study, we demonstrate that inclusions of plants, lichens and fungi can significantly support the reconstruction of amber forests. We evaluated the paleoecology of various seed plants based on data from comparable Paleogene fossils and assessed the functional morphology of fossil lichens and microfungi. Our recent survey of Baltic amber also significantly increased the total number of fossil lichens and fungi that are highly specific to certain forest types and climatic conditions. Inclusions of seed plants point to near-coastal lowland habitats such as coastal swamps, back swamps and riparian forests, as well as mixed-mesophytic conifer-angiosperm forests with open areas. The assemblage of seed plants, lichens and calicioid fungi suggests warm-temperate humid but relatively well-illuminated temperate forests in the source area of Baltic amber.

Host: Prof. Dr. Julia Bechteler

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14 May 2025

Dr. Claude Patrick Millet, DIADE, IRD, Montpellier, France.

Coffee genetic resources and agrobiodiversity in Haitian agroforestry systems: a multidisciplinary view

Haitian coffee agroforestry systems (CAFS) are crucial to rural livelihoods and local biodiversity. They face significant problems which, to be solved, require better knowledge of their agrobiodiversity (i.e. diversity of living beings in agricultural systems). We studied farms in two Haitian coffee (Coffea arabica) growing regions through the lens of genetic diversity, history, ecosystem services, and the interrelation of their components.
We sampled 28 CAFS to capture the local diversity of cultivated coffee and, through targeted genotyping and population genetics analyses, assigned them to one of five varietal groups, both traditional and more recent. We also identified inter-varietal hybrids. Our analyses revealed considerable genetic diversity in Haitian farms, higher in fact than many farmers realized. We investigated the historical determinants, local and global, of the island’ genetic resources, which reflect the broader history of Arabica varietal development and spread.
Finally, we described the broader agrobiodiversity of Haitian farms. We described farm typologies based on coffee, shade tree and associated crop diversity, as well as the ecosystem services they support; and investigated associations between them. Most CAFS occurred on a spectrum of farm regeneration (old to renewed coffee plots) tied to the adoption of “modern” coffee varieties, with implications for ecosystem services. Our studies of Haitian farms paint a picture of diverse, complex, and dynamic systems.

Host: Seraina Rodewald

21 May 2025

Prof. Dr. Ovidiu Paun, University of Vienna, Austria.

The drivers of plant adaptive radiations

Host: Prof. Dr. Gudrun Kadereit

28 May 2025

Dr. Omer Nevo, iDiv and Friedrich Schiller University Jena, Germany.

The chemical ecology of seed dispersal

Host: Dr. Elizabeth Joyce

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04 June 2025

Dr. Constantin Zohner, ETH Zurich, Switzerland.

Shifting seasons: How climate change is rewriting the rhythms of life in temperate and boreal trees

Climate change is shifting the timing of spring leaf-out and autumn leaf senescence in trees, with major implications for ecosystems and the carbon cycle. In this seminar, I will present my research on the external and internal drivers of spring and autumn phenology in temperate and boreal trees. By disentangling the roles of temperature, photoperiod, chilling, and internal physiological feedbacks, we gain clearer insight into how tree phenology is responding to warming and what this means for predicting future vegetation dynamics and growing season trends.

Host: PD Dr. Andreas Fleischmann

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11 June 2025

Dr. Christian Printzen, Senckenberg, Frankfurt, Germany.

Lichens of southern South America and their biogeoraphic relationships

The southern tip of South America is a perfect natural laboratory for studies on lichen diversity. Because lichens are sensitive to all kinds of disturbances their diversity is usually highest where human impact is low. The Magellanes Region is sparsely populated, largely unaffected by pollution and supports a unique range of habitats including seashores, steppes, the world’s southernmost forests and andean vegetation. More than 60 % of the region are national parks. In these habitats, a mixture of biogeographical elements is found: genera largely absent from the northern hemisphere with species endemic to South America, species shared with Australia or Antarctica and bipolar taxa. My lecture I will present examples for biogeographical elements found in the Magellanic Region and highlight different approaches to reconstruct their phylogeographic history. The Magellanic Region represents a hotspot of lichen diversity increasingly threatened by human impact.

Host: PD. Dr. Andreas Beck

16 June 2025 (Monday)

Dr. Fabian Michelangeli, New York Botanical Garden, New York, U.S.A.

The changing landscape of Melastomataceae systematics and taxonomy

Host: Prof. Dr. Gudrun Kadereit

18 June 2025

Dr. Kenneth Mertens, Ifremer/Brest, France.

Anarchy in the Plankton: Dinoflagellate Evolution

Host: Prof. Dr. Marc Gottschling

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25 June 2025

Prof. Dr. Susann Wicke, University of Münster, Germany.

Evolution and development of parasitic plants

Parasitism in plants represents the most extreme interaction between two plants, relying on specialized feeding organs that tap into the vascular systems of a host plant for water and nutrients. The shift from a self-sustaining, autotrophic lifestyle to parasitism entails profound genomic, morphological, and physiological changes—though some may predate parasitism itself. This talk highlights the Orobanchaceae, a plant family marked by multiple independent transitions to obligate parasitism and a non-photosynthetic lifestyle. We will explore how parasitism evolves and how weediness may emerge, using evolutionary, ecological, and developmental lenses across the parasite’s life cycle. Integrating high-throughput sequencing, advanced bioinformatics, and imaging technologies, we will examine key developmental and genomic shifts that accompany parasitic specialization. Special focus will be given to the roles of persistent soil seed banks, haustorial networks, and lineage-specific de novo proteins that underpin the ecological and evolutionary success of parasitic Orobanchaceae.

Host: Prof. Dr. Gudrun Kadereit

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02 July 2025

Dr. Karin Tremetsberger, BOKU University, Vienna, Austria.

Evolution and conservation of steppe plants in Central Europe

As an extrazonal vegetation type, steppes cover only a small part of Central Europe, yet they harbour a great diversity not only of plant and animal species, but also of their intraspecific genetic variability. Through the comparative analysis of this genetic diversity in steppe plant species and starting from a Eurasian perspective, we have gained a deeper understanding of the genesis, age, current status and endangerment of steppe species in Central Europe. In this seminar I would like to build a bridge from the origin of the Central European steppe biota to its present state and possible future.

Host: Dr. Simon Pfanzelt

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09 July 2025 at 3:15 pm

Ryan F. A. Brewer, Naturalis Biodiversity Center, Leiden, Netherlands.

Angiosperm evolution and biogeography across the floristically diverse Canary Islands archipelago

Islands offer unique opportunities to study the uneven distribution of biodiversity across the tree of life over time. Insular biotas are composed of lineages with different ages, species numbers, and traits, originating from the continent (or other islands/island regions), and converging within the same geographical arena. A prominent example of this is the flora of the Canary Islands, which comprises many spectacular species-rich radiations and dozens of depauperate, single-species lineages. However, the causes of the unevenness across the tree of island life remain largely unresolved. Here, we present a time-calibrated phylogenomic tree of life for Canary Islands angiosperms, including 671 species of native Canary Islands flowering plants, representing 435 lineages (~50%), and 770 closely related mainland taxa, to address the causes of unevenness in the flora. We find that Canarian flowering plants are the result of 881 independent colonisation and, overall, the flora is characterized by remarkably high extinction and colonisation rates that maintain macroevolutionary equilibrium, without a correlation between lineage age and species diversity. Insular woodiness acts as a key innovation and insular woody lineages have higher speciation rates and lower extinction rates relative to the rest of the flora, with rates of colonisation and cladogenesis declining as species richness increases; in non-insular woody clades, diversity appears unbounded, limited by high turnover rates. Our results reveal that macroevolutionary processes in the iconic Canary Islands flora are not primarily determined by lineage age but rather by the interplay of multiple factors operating over more than 20 million years.

Host: Dr. Thibaud Messerschmid

23 July 2025

Florian Altegoer and Michael Feldbrügge, Institute of Microbiology Heinrich Heine University Düsseldorf, Düsseldorf, Germany.

From microbial networking principles to lichen symbiosis: Insights from CRC1535 MibiNet

The Collaborative Research Centre CRC 1535 "MibiNet" (Microbial Networking – from Organelles to Cross-Kingdom Communities) aims to unravel how microbial networks form, function, and evolve across different scales — from the subcellular level of organelle interactions to complex cross-kingdom communities. Central to this effort is the identification of key network hubs and predominant metabolic, regulatory, and physical interactions across scales. Natural model systems such as the Peltigera lichen symbiosis serve as platforms to explore fundamental principles of microbial interaction and network organization.
Lichens are among the most ancient and fascinating examples of complex microbial communities. In lichens, a fungal mycobiont tightly associates with an algal and/or cyanobacterial photobiont to form complex morphological structures. Despite extensive research, the molecular mechanisms that govern lichen symbioses remain poorly understood. We here focus on the genus Peltigera that serves as a model for cyanolichens, with Nostoc cyanobacteria as its core photobiont. Using metagenomics, transcriptomics, and protein structure prediction, we analyzed multiple Peltigera isolates to dissect community composition and molecular interactions. Our study provides near chromosome-scale genomic data for several Peltigera mycobionts complemented by metagenomic data of their associated communities. We identified expanded classes of secreted proteins, including candidates with potential antimicrobial activity that may modulate microbiome composition, and a diverse array of fungal G-protein coupled receptors (GPCRs) resembling those of phytopathogenic fungi. These findings offer new insights into the molecular mechanisms underlying the initiation and maintenance of complex microbial interactions.

Host: Prof. Dr. Silke Werth

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30 July 2025 at 12:30 in room 109

Prof. Dr. Diego Batista and Dr. Juliane Henschel, Federal University of Paraíba, Paraíba, Brazil.

Pereskia genus as a key to understanding the evolution of CAM plants in Cactaceae

The genus Pereskia, considered ancestral to all other cacti, is distinguished by its woody stems and true leaves. Pereskia species are facultative CAM plants, meaning they can perform both CAM and C3 photosynthesis depending on water availability. In this talk, we present research conducted during a sabbatical year at the University of Liverpool, where we describe and characterize for the first time the transition between C3 and CAM and the molecular and biochemical mechanisms underlying these responses in four Pereskia species from Latin America under varying water availability. Understanding these mechanisms is crucial for supporting phylogenetic analyses of the Cactaceae family, guiding genetic engineering programs aimed at developing plants with high water-use efficiency in the face of climate change, and aiding in the conservation of these species, some of which are endangered.

Host: Dr. Renata Callegari Ferrari