Ecophysiology of desiccation tolerant criptogamic crusts (tropical ecophysiology)


It has long been known that phylogenetically diverse species of lichens, algae, bryophytes, ferns, and flowering plants can survive for days to years in a highly desiccated state and then resume normal growth. This most extreme tolerance of water stress occurs in desiccation-tolerant (DT) plants, which withstand drying of their photosynthetic cells to water contents 10% or less of their dry weight. In other words, these specialized plants are capable of surviving the loss of at least 90-95 % of their cell water content. DT plants are important constituents of many ecosystems from the tropics to the arctic regions; therefore significant aspects of ecosystem function depend on the function of DT plants. Thus any analysis of the Earth's vegetation requires investigation of DT plants and vegetation. On the Earth the tropical and subtropical regions the inselbergs as ecologically isolated habitats from the surrounding areas are evolutionary centres of the DT plants species and vegetations, which are the key ecosystems of plant taxonomical and functional diversity. The limits of tolerance, the suites of physiological, anatomical, and molecular changes that accompany desiccation, and the effects of desiccation on plant metabolism and ecological processes have each been documented in a variety of species.

During our research we search the responses for next questions: What is the mechanism of desiccation tolerance? Why is the ability to tolerate desiccation, seemingly so advantageous a trait for land plants, nevertheless relatively so rare among the flowering plants, especially the dicot species, and yet why is the DT mechanism re-evolved many times during the evolution of land plants? What are the key features of the structure and function of vegetations dominated by poikilohydric desiccation-tolerant plants? An integrative approach is needed to piece the answers together.

The research carries out in the ecophysiology laboratory of the Institute.

Participant:

Partners: Tamás Pócs (Eszterházy Károly Collage, Hungary), Nie Lei (Foshan University, China), Stefan Porembski (University of Rostock, Germany), Dinesh Saxena (Bareilly Collage, India).

Projects:

2001-2003 - DAAD-German-Hungarian scientific cooperation: ‘Investigations of vascular and non-vascular desiccation tolerant plants’
2007-2008 – TéT-China Chinese-Hungarian bilateral project: ’Ecophysiological investigation of desiccation tolerant plants of tropical inselbergs’

Publications

Péli E.R., Nie Lei, Tamás Pócs, Zsanett Laufer, Stefan Porembski, Zoltán Tuba (2011): Ecophysiological responses of desiccation-tolerant cryptobiotic crusts. Central European Journal of Biology, 6:(5) pp. 838-849. DOI: 10.2478/s11535-011-0049-1.
Péli E.R., Laufer Zs., (2010): A trópusi kriptobiotikus kérgek ökofiziológiai válaszai több éves kiszáradást követő újranedvesedés hatására. In: Botanikai, növényélettani és ökológiai kutatások. (Szerk: Nagy, Z., Bartha, S.), 161-168.
Nie L., Péli E. (2007): Some ecophysiological properties of cyanobacterial crypotogamic crust of tropical desiccation-tolerant vegetation. Cereal Research Communications, 35(2):849-852.
Tuba Z., Nie L., Péli E., Pócs T., Porembski S., Laufer Zs. (2007): Chlorophyll fluorescence and CO2 assimilation of desiccation-tolerant cyanobacterial crustaceous layer of tropical inselberg rock surfaces after rehydration following one and four-year air-dried stage. South African Journal of Botany, 73 (3): 500-501.
Péli E., Laufer Zs., Nie L., Tuba Z., Pócs T., Porembski S. (2007): Ecophysiology of desiccation-tolerant cyanobacterial cryptobial crusts of tropical inselberg: chlorophyll fluorescence and CO2 assimilation responses to rehydration followed prolonged air-dried period. Indo-hungarian scientific workshop, Biology of Inselberg plants, Ecology and machanism of desiccation tolerant plants and veetation in tropical inselberg. 16-24 March., Bareilly Collage, Bareilly, India.
Nie L., Péli E., Tuba Z. (2005): Ecophysiological strategies of desiccation-tolerant crustaceous cryptogamic layer on tropical inselbergs. In: Abstracts of XVII International Botanical Congress, Vienna, Austria, P1886, 535.