Impact of heat stress on expression pattern of nine rice heat shock factor genes and its traits related to tolerance.

Global warming is unusually increasing the earth temperature over the past century at an average rate of 0.07°C per decade since 1880. The increased temperature exhibit greater impact on grain yield, approximately 5.18 million tons of rice yields due to heat wave. Heat shock factors (HSF) has major role in regulating heat shock proteins which in turn responsible for survival of plants in heat stress by refolding proteins, maintaining functional confirmation, aiding in host defence mechanism. The aim of this research was to analyse phenological, biochemical changes and key genes highly expressed during heat stress at flowering stage in rice. Expression analysis of nine HSF genes had given a differential expression under heat stress as compared to controlled traits. This study suggested OsHSP26.7 as most responsive gene under heat stress and rice line 159, RRF-127, GP-145-103 and Annada with heat tolerant adaptive mechanisms and better performance under high temperatures and was found to be in correlation with the estimated biochemical traits. This can be taken as a base for heat tolerance response of the crop, which may be useful for further validation studies of the candidate genes for heat tolerance in the rice as well as other crop plants. [ABSTRACT FROM AUTHOR]