ESTIMATION OF GENETIC VARIABILITY, HERITABILITY AND GENETIC ADVANCE IN RICE (ORYZA SATIVA L.)

The Present study was carried out to estimate the genetic variability, heritability and genetic advance for grain yield and its attributes in rice (Oryza sativa L.) under irrigated conditions during Kharif 2022 at Agricultural Research Farm, Institute of Agricultural & Natural Sciences, DDU Gorakhpur University, Gorakhpur (U.P.), India. Fifteen different rice genotypes were used in a randomized block design with three replications and data was recorded for grain yield per plant and twelve yield contributing characters. The results of analysis of variance revealed highly significant differences among genotypes for all characters, establishing the existence of high genetic variability. Grain yield per plant recorded a wide range from 22.00 to 38.67 g with very high heritability (95.9%) and genetic advance as percent of mean (40.59%), establishing a strong possibility for improvement through selection. Effective tillers per plant varied from 7.67 to 23.33, establishing high variability (GCV 32.02%, PCV 33.17%) and high genetic advance (63.66%), establishing the predominance of additive gene effects. Biological yield varied from 48.36 to 78.59 g, with very high heritability (98.7%), GCV 17.46% and genetic advance (35.58%). Plant height varied from 87.17 to 151.67 cm and recorded high heritability (97.7%) with GCV/PCV 16.48% and genetic advance as percent of mean 33.16%. Days to 50% flowering (97.00- 133.67 days) and days to maturity (125.67-161.67 days) also recorded high heritability (96.6% and 94.1%, respectively). Grain breadth recorded comparatively low heritability (31.7%) and low genetic advance (6.69%), establishing a limited scope for improvement through selection. Overall, high heritability coupled with high genetic advance for grain yield per plant, effective tillers per plant, biological yield and plant height suggests that these traits can be effectively utilized as reliable selection criteria for improving rice productivity.