Analysis of Genetic Variability, Heritability and Genetic Advance in Advanced Breeding Lines of Rice (Oryza sativa L.) for Yield and Quality Traits

Abstract

The present study was undertaken to assess genetic variability and divergence among 36 advanced breeding lines of rice (Oryza sativa L.) under field conditions at the experimental farm of Rice and Wheat Research Centre, Malan during Kharif, 2023. The experiment was laid out in a randomized block design with three replications, six agro-morphological and eleven grain quality traits were evaluated. The results revealed that significant genotypic differences were observed for all traits indicating ample amount of genetic variability in the material under study. Notably, moderate to high phenotypic and genotypic coefficients of variation were observed for key traits such as effective tillers per plant (21.95 and 20.69, respectively), grain yield per plant (28.46 and 26.06), grain breadth (11.05 and 10.59), grain L:B ratio (11.15 and 10.50), kernel breadth before cooking (13.19 and 12.46) and kernel L:B ratio (12.51 and 11.31). High heritability (>80%) coupled with high genetic advance (>20%) was recorded for several traits, including effective tillers per plant (88.87 and 40.18, respectively), grain yield per plant (83.80 and 49.14), grain breadth (91.82 and 20.90), grain L:B ratio (88.65 and 20.36), kernel breadth before cooking (89.31 and 24.26) and kernel L:B ratio (81.78 and 21.07) indicating the predominance of additive gene action and scope for effective selection. These findings suggest that seed yield and its contributing traits could serve as reliable selection indices in the breeding programs, providing valuable insights for the development of improved cultivars with higher productivity and desirable agronomic characteristics.