Lichens of the Alps (Hafellner, Mayrhofer, Obermayer)
Since many years, the Alps have been in the focus of intensive lichenological research by members of our group. The Alps are among the most-species rich areas for lichens and also a potential cradle of lichen diversification. This diversity is due to high density of ecological niches with varied substrate types and microclimatic parameters. Our research in these habitats is focused on characterization of lichen diversity in different habitats that frequently leads to a revised concept of species. Subtopics of this research theme are: Lichens on special rock substratesAlpine lichens as niches for associated fungi, and lichenological base line studies of summits in the Eastern Alps. Selected publication: Hafellner, J., Kärnefelt, I. & Wirth, V. (eds.) 2010: Diversity and Ecology of Lichens in Polar and Mountain Ecosystems. Bibliotheca Lichenologica 104: 1-389.
Lichen biota of selected geographic regions (Hafellner, Mayrhofer, Obermayer)
Members of the lichen workgroup have specialised on lichen biota of various parts of the world, where we contributed to a comprehensive overview of lichen diversity. This work is usually conducted in cooperation with international partners, and thoroughly documented by reference material maintained in our lichen herbarium (GZU). Austria, with focus on Styria (Hafellner, Obermayer, Mayrhofer), Balkan peninsula, Armenia and Tajikistan (Mayrhofer), Tibetan Region incl. Himalaya, Karakorum and Hengduan Shan (Obermayer), Albania (Hafellner).
Phylogeny and taxonomy of lichen-forming fungi, including lichenicolous fungi (Grube, Hafellner, Mayrhofer, Obermayer)
We investigate the phylogeny of lichen symbioses at various levels of resolution. Of particular interest to us is the level of species and genera in crust-forming microlichens. Recognition of species and their correct naming is a mainstay of biological research and communication. For this reason we are concerned with detailed taxonomic investigations in problem areas of systematics of lichens and lichenicolous fungi.
Population genetics and genomics of lichen-forming fungi and their photobionts (Werth)
We study the population structure of lichen symbioses at different spatio-temporal scales, using various methodological approaches (microsatellites, RAD-seq, RNA-seq). A central question is how lichen-forming fungi respond to biotic and abiotic environmental variation, including stressful conditions. We address this question with controlled laboratory experiments, or field experiments, where we relate variability in mycobiont and photobiont gene expression to biotic and abiotic factors of interest. Our model organism is Lobaria pulmonaria, and we also study other taxa belonging to the order Peltigerales. Selected publication: Steinhäuser SS, Andrésson ÓS, Pálsson A & Werth S 2016. Fungal and cyanobacterial gene expression in a lichen symbiosis: Effect of temperature and location. Fungal Biol 120;1194-1208.
Lichen-associated bacteria (Grube)
Lichens represent stable and diverse ecological niches for other micro-organisms. We have identified and localised the diversity of lichen-associated bacterial communities and found biofilm-like colonization of fungal matrices by diverse bacteria. The lichen microbiota are topic of continued research activity, in cooperation with Graz University of Technology, and further international partners. Selected publication: Grube M, Cernava T, Soh J, et al. 2015. Exploring functional contexts of symbiotic sustain within lichen-associated bacteria by comparative omics. ISME Journal 9:412-424.
Selectivity in lichen symbioses, including association with bacteria (Grube)
Lichen associations display various levels of levels of selectivity for their algal symbionts. Different strategies ensure successful association with their partners. We study the specificity of symbiotic associations using molecular sequence data. Lichens represent stable and diverse ecological niches for other micro-organisms. Using confocal microscopy and molecular probes, we have identified and localised the diversity of lichen associated bacterial communities and found biofilm-like colonization of fungal matrices by diverse bacteria, generally with a predominance of Alphaproteobacteria. The lichen bacteriome is topic of continued research activity, in cooperation with Graz University of Technology, and further international partners. Selected publication: Grube M, Cardinale M, Vieira de Castro J, Müller H, Berg G 2009. Species-specific structural and functional diversity of bacterial communities in lichen symbiosis. ISME J 3: 1105-1115.
Myxogastria are representatives of the so-called slime mould, which are traditionally studied by mycologists. Some of these organisms develop large and dynamic network structures, which became very attractive as a model for studying biological information processing. We are investigating the adaptivity of these structures, and more recently also the diversity and evolution of these organisms which are also classified as protozoa. Selected publication: Westendorf, C., Gruber, C., & Grube, M. (2016, May). Quantitative comparison of plasmodial networks of different slime molds. In proceedings of the 9th EAI International Conference on Bio-inspired Information and Communications Technologies (formerly BIONETICS), pp. 611-612.
Biodiversity of microfungi (Scheuer)
Under this research topic, we are dealing with various groups of non-lichenized fungi, e.g. small saprobic sac fungi (ascomycetes) on plant material. Another mission is to continue the inventory of plant parasitic microfungi in Austria and adjacent areas, mainly of anamorphic ascomycetes, rust and smut fungi, downy and powdery mildews. The university herbarium of Graz (GZU) holds one of the most valuable recent collections of those fungal groups in Europe.
Ecological applications with lichens (Hafellner)
Lichens are sensitive indicators of air pollution and more generally, for microhabitat conditions and ecological factors. Therefore the application of lichens as indicator species for ecologically valuable old growth forest remnants is studied in the Eastern Alps. We also use lichenological data to corroborate the value of nature conservation areas. Selected recent publication: Hafellner, J. 2009: Zur Flechtendiversität im Natura 2000-Schutzgebiet Raabklamm (Österreich, Steiermark). – Mitt. Naturwiss. Vereines Steiermark 139: 83–126.
Diversity of lichenicolous fungi and their biotic interactions with lichen symbionts (Hafellner, Grube, Werth)
Fungi that have specialised to colonise lichens are generally called lichenicolous fungi. Their biology is varied, ranging from highly adapted commensals, which do not seem to harm their lichen hosts, to highly destructive species. Most of the c. 1800 named lichenicolous fungi evolved from lichen ancestors and have specialised on particular host lineages. The diversity of these fungi is still underestimated. We have been able to discover and describe a considerable number of species during the past decades in this biological group of fungi. In addition to taxonomic work, we also study the effect of lichenicolous fungi on gene expression of their lichen hosts. Selected publications: Muggia L, Fleischhacker A, Kopun T & Grube M (2016) Extremotolerant fungi from alpine rock lichens and their phylogenetic relationships. Fungal Diversity 76: 119-142. Spribille T, Tuovinen V, Resl P, et al. (2016) Basidiomycete yeasts in the cortex of ascomycete macrolichens. Science 353: 488-492.
- Mayrhofer: P26359 Hyperdiversification of extromotolerant fungal symbioses - FWF
- Mayrhofer: P25237 Evolution of substrate specificity in lichens - FWF
- Mayrhofer: P25078 Lichens of the Alps: diversity and climate change - FWF
- Mayrhofer: P21052 Diversification of circumboreal lichens - FWF
- Mayrhofer: P20842 Lichen biodiversity in refugia of the dinaric mountains – FWF
- Muggia: T481 Artenevolution in Symbiose – FWF
Institut für Biologie
Institut für Biologie