Impact of Drought Stress on Some Grain Quality Traits in Rice(Oryza sativa)

摘要

The study was conducted to ascertain the harmful effects of drought stress on grain quality traits in rice. For the purpose, grain shape quality traits of twenty rice genotypes were studied in order to understand the effects of drought stress on thesequality traits. The result of analysis of variance clearly indicates that genotypes significantly differ in grain quality traits under both normal as well as drought prone environments. Higher heritability estimates for grain length and length to widthratio under normal and all quality traits under stress environment indicate that these characters are controlled by multiple genes and selection of these characters would be effective at early generation. Results showed that grain length was positively correlated with length to width ratio (0.863* and 0.668*) and negatively correlated with grain width (— 0.614** and -0.313**) and grain breadth (-0.321**and -0.030ns) under both normal and stress conditions respectively. Grain width was positively correlated with grain breadth (0.711** and 0.486**) and negatively correlated with length to width ratio (-0.926* and -0.910*) under both conditions respectively. Grain width was highly correlated with yield per plant (0.386** and 0.315**) under both, normal and drought stress respectively while grain breadth was positively correlated (0.553**) only under normal condition. It shows that reduction in grain width has direct effect on grain yield. Under normal condition, yield was positively correlated with grain width (0.386**) and grain breadth (0.552*) indicating that grain width and grain breadth should be considered while screening high yielding genotypes under normal condition and grain width alone should be considered for drought stress among the studiescharacters.