Variability, heritability and genetic advance for yield and its component traits in NPT core set of rice (Oryza sativa L.)

Presence of adequate genetic variability and its critical analysis are needed for initiating any crop improvement programme and for adopting appropriate selection techniques. An investigation was carried out to know the extent of genetic variability present in forty six genotypes of rice during kharif 2017. Analysis of variance revealed highly significant differences for all the 12 characters, indicating the presence of genetic variability among the genotypes. The magnitude of PCV was slightly higher than GCV for the traits viz., plant height, number of tillers per plant, number of panicles, panicle weight, grain number, test weight, single plant yield, plot yield and biomass, indicating less influence of environmental factors on the expression of traits and the possibility for genetic improvement through direct selection for these traits. The estimates of PCV and GCV were moderate for the traits viz., days to 50% flowering, panicle length and harvest index, indicating the influence of environment rather than the genotype alone. The heritability and genetic advance estimates were moderate for panicle length and high for all the other traits viz., days to 50% flowering, plant height, number of tillers per plant, number of panicles, panicle length, panicle weight, grain number, test weight, single plant yield, plot yield, biomass and harvest index, indicating the influence of additive gene action, as such selection would likely be effective for improvement of these traits.