Drought stress is the most devastating abiotic stress which severely affects starch biosynthesis, thus altering the glycemic index (GI) of rice grains. It shortens the period of grain filling by rapidly translocating assimilates to grains, thereby decreasing amylose content (AC), resistant starch (RS), and increasing GI value. Among 30 genotypes tested, ZHU-11-26, IR 20, and Annada differ in exhibiting a much lower reduction in AC and RS which result in insignificant change in GI (<1) under drought stress. Two genotypes (ZHU-11-26 and Pathara) are selected for granule bound starch synthase I expression analysis on the basis of their contrasting GI and RS content. The gene is highly and significantly expressed at the dough stage of grain development and shows a positive association between its expression and RS content. Drought is very common in most parts of the world in the present climate-change scenario, where even mild terminal stress may affect grain filling rate and cause the increment in GI value of grains. In this context, identification of less responsive genotypes with a lesser change in GI under drought stress may help in developing rice varieties for the diabetics even grown under stress-prone environments.

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6Rice production is severely threatened by drought stress in Eastern India. To develop drought tolerant 3 7 varieties, selection of donors for breeding programme is crucial. Twenty one selected rice genotypes including 3 8 both tolerant and sensitive to drought were grown under well-watered and drought stress conditions in dry 3 9 seasons of two successive years of 2017 and 2018. Leaf water potential, relative water content displayed 4 0 significant difference among the genotypes during vegetative screening. At reproductive stage drought 4 1 screening, days to 50% flowering was delayed in all genotypes except N22 and Anjali (showed early flowering) 4 2 however grain yield and other yield related traits decreased significantly compared to well-watered condition. 4 3 Correlation analysis of phenological and yield related traits with grain yield revealed that tiller numbers and 4 4 panicle numbers are highly correlated with grain yield both under well-watered and water stress conditions and 4 5 contributes maximum towards grain yield. The dendrogram grouped Mahamaya, Sahabhagidhan, Poornima, 4 6 IBD 1, Hazaridhan, Samleshwari and Danteshwari into one cluster which performed better under water stress 4 7 conditions and had grain yield more than 1.69 tha -1 . Sahabhagidhan, Poornima, Vandana, and N22 displayed 4 8 tolerance to drought both under vegetative and reproductive conditions which could be a good selection for the 4 9 breeders to develop drought tolerant rice cultivars for eastern region of India.5 0