Abstract:
The present study was undertaken to screen the thermotolerant varieties of soybean and analyse the changes brought about by heat shock conditions in least resistant variety. Four varieties of soybean viz., Williams, Chippewa. S-73 and Improved Pelican were subjected to 7 different heat shock conditions. 'Chippewa' was found to be the most theremotolerant and 'Williams" was the least. It was observed that 45°C-2 h had lethal effect on growth of soybean seedlings. A short pulse of 10 minutes at 45°C triggers the synthesis of some heat shock proteins which were accumulated at 45°C-2 h and then gradually decreased during recovery period. Altered levels of RNA, DNA. total phenols and anthocyanins were also observed in cv. Williams. An increase in temperature had adverse effect on growth however, Hsps-induced during shock may help in the recovery of growth and provide thermal tolerance in soybean seedlings.
