Estimation of gene effects through generation mean analysis in elite rice (Oryza sativa L.) crosses

Abstract

An experimental was carried out to study the gene action governing yield and its attributing traits for three crosses utilizing five diversified rice genotypes at Regional Agricultural Research Station, Warangal. The experimental material consisted of six generations (P1, P2, F1, F2, BC1 and BC2) obtained from three crosses using five parents laid out in a randomized block design with three replications to study the generation mean analysis for yield and yield attributing characters viz., days to 50% flowering (days), plant height (cm), total number of productive tillers per plant (Nos.), panicle length (cm), number of grains per panicle (Nos.), test weight (gm) and grain yield per plant (gm). The Generation mean analysis indicated the presence of epistasis in expression of grain yield and its components. The interaction was of duplicate epistasis, therefore, in addition to the main genetic effects, ([d], [h] components, the interaction components were also taken into consideration to develop the breeding strategy. Prevalence of significant additive effects in the crosses MTU1010 x NH-686, RP-Bio-5478-185 x NH-787 indicated effectiveness of direct selection for yield improvement. The interaction components are highly variable; therefore, a cross and trait specific breeding strategy i.e direct selection and development of pure lines are appropriate for yield improvement.