Heat-induced changes of chlorophyll fluorescence in intact leaves correlated with damage of the photosynthetic apparatus.

摘要: Methods were developed to measure chlorophyll fluorescence yield of intact leaf tissue during heat treatment under varying conditions light intensity and photosynthetic activity. Fluorescence a dark-adapted increases by 2- 3-fold with an increase temperature into the region where heat-damage occurs. The temperatures transition correlate well quantum CO2 fixation is irreversibly depressed. Fluorescence-temperature (F-T) curves allow ranking different species according their sensitivity. Within single acclimation growth reflected shifts in F-T curves. When are recorded steady states at increasing intensities, substantial (up 6°C) higher values observed. Quantum measurements confirm that hight-light protect from heat-damage. It suggested acts as intrinsic probe thylakoid membrane responds same changes which cause irreversible denaturation enzymes.