Botanik Seminar
Ein gemeinsames Seminar des Lehrstuhls für Systematik, Biodiversität & Evolution der Pflanzen, der Botanischen Staatssammlung München und des Botanischen Gartens München-Nymphenburg
Wann? Mittwochs
- Mittwochs um 13:15 Uhr (während des Semesters, wenn nicht anders angegeben)
Wo?
- Kleiner Hörsaal (Raum 109) im Botanischen Institut, Menzinger Str. 67, 80638 München.
Program sommer semester 2025
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
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
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
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
From June on, the seminars will be in the Big Lecture Hall of the Botanical Institute
04 June 2025 (in the Big Lecture Hall): 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
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
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
02 July 2025: Dr. Karin Tremetsberger, BOKU University, Vienna.
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
09 July 2025: 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
16 July 2025: Prof. Dr. Johan Ceuster, from KU Leuven, Belgium.
Why it matters to study diurnal CAM biochemistry
As a specialized mode of photosynthesis CAM has evolved in different plant families and to different extents going from facultative to obligate CAM. A classical hallmark for all CAM species is the nocturnal acidification which results from PEPC-mediated carboxylation. The resulting malate ions are sequestered together with protons in the vacuole overnight, before releasing malate again during daytime to allow decarboxylation and Rubisco mediated CO2 assimilation behind closed stomates. These biochemical events present a considerable challenge for proton homeostasis in the leaf mesophyll cells but different aspects concerning the machinery behind the diurnal mobilization of malate and protons from the vacuole in CAM plants are still unknown. Knowledge gaps persist about the identity of the diurnal malate transporter in the tonoplast, the rate limiting steps in the decarboxylation process and the intracellular proton fluxes to safeguard the cytosol of leaf mesophyll cells from overacidification. By integrating physiological, biochemical, molecular and modelling approaches using the CAM species Phalaenopsis and Kalanchoë fedtschenkoi under different environmental conditions, our aim is to depict these biochemical events during daytime in much more detail. A more comprehensive insight into the diurnal biochemical processes in CAM plants might act as a further leverage to increase our understanding of the evolution of CAM in different plant lineages.
Host: Dr. Renata Callegari Ferrari
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
30 July 2025: 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
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