Differential accumulation of high and low molecular weight heat shock proteins in Basmati rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) cultivars

The accumulation of various heat shock proteins (HSPs) and their relationship with the inbuilt cold tolerance observed in Kashmir Basmati was studied. Five Basmati rice verities (Oryza sativa), Basmati-370, Basmati-Pak, Basmati-198, Basmati-385 and Kashmir Basmati were given temperature shock of 45 and 50°C. Temperature shocks were given for 16 h in incubator preheated to 45 and 50°C and 85% relative humidity. Proteins were extracted and separated on 10% acrylamide gels with 1 mm thickness and visualized for protein fractions. Accumulation of 40 kDa HSPs were observed in all the cultivars, and 20 kDa HSPs specifically in Kashmir Basmati. Small amounts of high molecular weight HSPs were observed in un-treated (control) plants of Kashmir Basmati, and it increased considerably after heat shock. The 20 kDa HSP was only expressed in heat-treated Kashmir Basmati. Differences in the expression of heat shock proteins in the tested varieties have been described in detail.