Abundant variability, heritability and extent of association between yield related traits in the initial breeding material ensures better chances of producing desired forms of a crop plant. In order to study genetic variation, genetic inheritance, genetic advancement, and the relationship between yield and related characteristics of 16 advanced rice cultures, the experiment was carried out with rainfed condition. All of the treatments have significant implications for the numerous features under study, according to the analysis of variance. Straw yield had a moderate GCV and the number of effective tillers per plant, number of spikes per square metre plot area, grain yield, straw yield and harvest index showed the highest magnitude of PCV. Days to 50% blooming was shown to have a high genetic gain and high heritability, which suggests that additive gene action plays a substantial role in the generational transmission of this feature. Harvest index was found to have a positive correlation with days to 50% blooming, number of spikes per square metre and length of the panicle. These results suggest that selecting for harvest index will help develop high-yielding genotypes in rainfed environments by simultaneously improving these traits. Straw yield showed very high direct effects, while the harvest index had a high direct effect on grain production. To increase grain yield under rainfed rice cultivation, greater weight should be placed on the characteristics of days to 50% blooming, straw yield and harvest index. Hence result obtained from this study is paving way for rapid improvement in yield in rainfed environment by considering these mentioned traits during selection process.

Variability, heritability, genetic advance, trait association, rainfed rice

The variability investigations lead to the conclusion that days to 50% blooming is a variable that is mostly inherited by additive gene action and has a high heritability and genetic progress. In the rainfed rice habitat, this characteristic could therefore be used as useful selection factors throughout the breeding program. According to association studies, in order to increase grain yield under rainfed rice farming technique, greater weight should be placed on the characteristics of days to 50% blooming, straw yield and harvest index.

Muthuramu S. and Thangaraj K. (2023). Genetic Variability, Heritability, Genetic Advance and Trait Association Studies in Rainfed Rice Genotypes. Biological Forum – An International Journal, 15(11): 108-112.