Elevated Temperature Treatment Induced Alteration in Thylakoid Membrane Organization and Energy Distribution between the Two Photosystems in Pisum sativum

Abstract

High temperature causes changes in the struc-tural organization of thylakoid membranes affect-ing excitation energy distribution as the well asrates of photochemical reactions. Thus, high tem-perature causes alterations not only in the physi-ochemical properties but also the functional or-ganization of the thylakoid membranes (Pastenesand Horton, 1996). Heat stress has been reportedto affect various photosynthetic processes includ-ing electron flow on the donor side of PSII (Nashet al., 1985; Enamiet al., 1994) and at the acceptorside of PSII (Bukhovet al., 1990; Cao and Govind-jee, 1990), inactivation of enzymes like ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) andferredoxin-NADP reductase (FNR),