Assessment of genetic variability for yield and its components in a Recombinant Inbred Line (RIL) population of rice (Oryza sativa L.) derived from Jaya × Goa Dhan 2

Abstract

The present study evaluated genetic variability in 244 recombinant inbred lines (RILs) and ten checks across thirteen traits. The trial was conducted during Rabi 2022–23 using an Augmented Randomized Complete Block Design. The analysis of variance (ANOVA) revealed significant differences among the RILs for all traits except total productive tillers and flag leaf length, confirming the presence of considerable variability. Grain yield ranged from 1249.27 to 10090.22 kg ha⁻¹ with 5023.97 kg ha⁻¹ as an average. Phenotypic variance was higher than genotypic variance for all the traits, although the difference was small. Likewise, the phenotypic coefficient of variation (PCV) was marginally higher than the genotypic coefficient of variation (GCV), with the highest values observed for grain yield (32.20, 34.31), followed by straw yield (33.71, 35.46) and plant height (21.03, 24.19). This indicates that these traits are predominantly under genetic regulation and can be exploited in selection. High estimates of broad-sense heritability combined with high genetic advance as percent of mean (GAM) were recorded for grain yield, straw yield, plant height, harvest index, and total grains per panicle, demonstrating that these traits are amenable to improvement through direct phenotypic selection. The considerable variability, strong heritability and substantial genetic advance detected for these traits offer valuable insights for rice breeders, enabling effective development of improved inbred lines through direct selection.