In vitro screening of gamma rays induced mutant population in rice for peg-induced drought stress

Abstract

The effects of gamma irradiation on rice genotype Rajendra Mahsuri 1 for drought tolerance capability were investigated. In this study a system for in vitro Screening of gamma induced mutant rice lines were optimized using polyethylene glycol (PEG-6000). Exposure to PEG-6000 solutions has been effectively used to mimic drought stress. The effect of different concentration of PEG-6000 (0%, 5%, 10%, 15% and 20%) on seed germination of wild type of Rajendra Mahsuri 1 were studied. The decrease in onset and rate of germination followed by their growth declines with increasing concentration of PEG-6000. The optimum concentration of PEG-6000 for screening irradiated Rajendra Mahsuri-1 lines was found to be 15%. The germination followed by survival of mutant lines was evaluated on 15% PEG-600. Five M2 lines each of different doses of γ-irradiation viz. 350 Gy, 400 Gy, 450 Gy and 500 Gy were used for in vitro screening. The maximum survival % of seedlings were observed in 450 Gy followed by 400 Gy. The survival % of seedlings on 350 Gy and 500 Gy were found to be less than 10%. Mutant rice line differed greatly in terms of germination followed by survival on 15% PEG-6000 which can be correlated their tolerance to drought stress.