Eco-physiology of abiotic stress tolerance in selected bryophytes

Title : Eco-physiology of abiotic stress tolerance in selected bryophytes

Abstract:

We are living in a rapidly changing world. The increase of harsh environments like the barren, metal spiked substrate of former mining sites exposed to high irradiation and drought are good examples. However, some organisms like bryophytes are pioneers to settle even in such inhospitable habitats. The reasons for this astonishing tolerance are remain largely unknown.
Here, we focus on four different bryophyte species (Physcomitrella patens, Pohlia drummondii, Mielichhoferia elongata, Atrichum undulatum), some occurring on metal spoil heaps, some are from uncontaminated sites. In laboratory experiments, the specimen were introduced to controlled amounts of copper or zinc (provided as -Cl₂, -SO₄, or -acetate) by addition to the substrate or application as simulated rain containing toxic metals. The bryophyte samples were analysed for growth parameters, primary and secondary metabolites, stress physiology markers and cellular localisation of metal deposition. Thereby, we can determine physiological traits that allow certain species to settle on barren substrate. The inclusion of model species like Physcomitrella patens allows for complementary analyses of abiotic stress tolerance at the proteomics level.

In general, it can be assumed that bryophytes contain evolutionary conserved resistance to some extent of zinc and copper contamination, and that the tolerance to zinc is higher compared to copper. The accumulation of copper can be documented better than zinc within moss tissues, which could be the reason for the higher toxicity of copper and higher tolerance to zinc. The mechanisms of resistance and tolerance, however, remain unclear and need to be further examined.

Biography:

In biological systems, structure and function are intrinsically tied to each other. Both areas have been fascinating to me as a plant scientist since the beginning of my studies. My scientific work is focussed on two major topics: (1) ecological aspects, like tolerance of plants towards heavy metals and their potential, intracellular uptake and (2) physiological aspects of salt- and UV-stress as well as water balance of cells and tissues. I am passionate about teaching and I am regularly giving lectures and lab courses in cell biology, plant physiology and anatomy, light microscopy and scientific documentation. For a couple of years now, I am leading a small group consisting of PhD, master and bachelor students at the Core Facility Cell Imaging & Ultrastructure Research, at the University of Vienna, Austria.