expression in numerous rhizobial species ( Nocker et al. 2001 ). The molecular bases of temperature stress tolerance in rhizobia had been investigated, by evaluating the expression of chaperone genes dnaKJ and groESL in thermotolerant and thermosensitive isolates. That is followed by low temperature adaptation that allows continued growth at low temperatures ( Panoff et al. 1997 ). Usually, bacteria overcome lack of fluidity by increasing the amount of unsaturated fatty acids in the membrane phospholipids ( Phadtare et al. 2000 ). Chilly shock response additionally leads to the production of many cold shock proteins (CSPs).