Fast chlorophyll a fluorescence kinetic analysis for the assessment of temperature and light effects: a dynamic model for stress recovery phenomena

摘要

High temperature and high light treatments seem to have an additive effect on photosynthetic efficiency of plants (Srivastava and Strasser, 1996). Heat stress with high light intensity alters the charge separation activity of PS II without affectingthe S-states in the donor side (Misra et al., 1997), induced degradation of D1 polypeptide and a block in the electron flow to Q_B (Misra et al., 1998) causing acceptor side photo inhibition. However, most of the effects of heat stress are caused by theprimary inhibition of PS II photochemistry at the donor side and also a block in the electron flow at the acceptor side (Cajanek et al., 1998). So the enhancement in the photoinhibition of photosynthesis at high temperature appears to be a complex phenomena. The present study aims at elucidating this complex mechanism of adaptive stress responses in plants.