Effects of Heat Stress on the Photosynthetic Apparatus in Commiphora wightii (Arnott) Bhandari

By : P.L. Swarnkar , Vineet Soni

Page No: 139-145

Abstract
Heat stress, whether transitory or constant, causes physiological, biochemical and molecular changes that adversely affect plant growth and productivity by reducing photosynthesis. To elucidate the photosynthetic adaption response under heat stress, we measured various photosynthetic parameters in C. wightii plants through polyphasic chlorophyll fluorescence OJIP analysis. Chlorophyll a fluorescence analysis indicates that plants are quite resistant and well developed physiologically to survive in heat stress conditions by maintaining their photosynthetic performance through increasing their light trapping and electron transfer efficiency at reaction center level. The high activity of reaction centers, despite their low density in heat strssed plants, indicate that the reaction centers have enhanced their activity to cope up with their meagre number. The study describes the physiological basis of heat tolerance and will, therefore, be useful in transgenics for the development of high temperature tolerant plants.

Authors :
Vineet Soni : Plant Bioenergetics and Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, India
P.L. Swarnkar : Department of Botany, University of Rajasthan, Rajasthan, Jaipur, India