LFU:online

Institut für Botanik Institut für Botanik

Dr. Othmar Buchner Dr. Othmar Buchner, +43 512 507 51062
ao. Univ.-Prof. Mag. Dr. Gilbert Neuner ao. Univ.-Prof. Mag. Dr. Gilbert Neuner, +43 512 507 51026
Mag. Manuel Pramsohler Mag. Manuel Pramsohler

717068

Stressphysiologie der Pflanzen (VO1, UE2)

VU 3

4,5

Block

2-Jahresrhythmus

Deutsch

Kenntnisse der Stressmechanismen und Resistenz bei Pflanzen sowie deren spezifische Anpassungsstrategien bei HItzeeinwirkung

Field course in plant stress physiology II: Heat stress (G. Neuner and O. Buchner) The effect of heat on alpine plants and the importance of heat resistance mechanisms are exemplarily depicted for the peculiar environmental situation of alpine habitats. By micrometeorological measurement the heat strain is investigated in alpine micro habitats. Fine scale scattering of temperature is visualised by Infrared Video Thermography. Artificial heat stress is applied in situ via field portable temperature chambers or by laboratory based standard methods. To gain a dose versus effect diagram a series of exposure times and temperatures is applied. To assess combined stress effects heat is applied in combination with a controlled drought stress treatment. After application of the heat treatment heat resistance is assessed by various viability assays such as the electrolyte leakage test, visual damage rating, chlorophyll fluorescence imaging, the TTC test and in re-growth studies (after in situ heat application). Standard and recently invented stress physiological methods to analyse and detect early warning signals of heat stress are demonstrated in case studies with alpine plant species mainly focusing on the photosynthetic performance: (1) The direct effect of heat on the photochemical efficiency of PS II is measured by the recording of so called F0-T curves on leaves investigating diurnal changes and effects of heat pre treatment. (2) The after effect of a heat treatment is documented by changes in respiration rates and the shape of the light response curves of CO2 gas exchange of C3 plants and (3) in alterations of the diurnal acid cycle of CAM species. (4) Significance of leaf movements of Oxalis acetosella for survival of combination stress is demonstrated. (5) Gel electrophoreses of leaf samples obtained before or after a controlled heat treatment allows showing changes in protein patterns by increased expression of heat shock proteins.

Online-Anmeldung erforderlich! Block: 06. - 10.06.2011
Beginn: VB, Mo 07.03.2011, 14.45 Uhr, HS A/Botanik

Block: 06. - 10.06.2011, Alpengarten Patscherkofel