GENETIC PARAMETERS AND SELECTION RESPONSE IN ADVANCED GENERATION (F5) OF FINE RICE

Abstract

A field experiment was conducted using 32 advanced generation (F5) derived from eight crosses during the period of Transplant Aman season from (July-December) of 2017, at Plant Breeding Research Field, to assess the extent of variability, heritability, genetic advance for yield and yield associated traits in rice. The experiment was laid down in a randomized complete block design with three replications. A total of 13 characteristics viz. plant height (cm), productive tillers/hill, (maximum vegetative stage), panicle length (cm), fertile grains/panicle, sterile grains/panicle, panicle weight (g), sterility percentage (%), lodging percentage (%), 1000-grain weight (g), grain yield/hill (g), days to 50% flowering, days to maturity and harvest index were studied. Analysis of variance indicated highly significant differences among the genotypes for all the traits under study. The means of different traits were separated by DMRT. The advanced line, PL29 derived from Badshabhog × Begunbichi produced highest grain yield/ hill (17.56g) but ranking of the advanced lines based on yield enhancing traits, 18 F5 derived from Kalozira × Badshabhog showed the best performance. The PCV were higher than GCV for all thirteen traits indicating that they all interacted with the environment to some extent. High heritability was observed for fertile grains/panicle (97.80) followed by plant height, productive tillers/hill, sterile grains/panicle, panicle length which indicates high heritable portion of variation. High to medium estimates of heritability and genetic advance value was recorded with fertile grains/panicle (37.82) followed by lodging percentage (8.88), plant height (13.78) and 1000 grain weight (6.79) indicating the roles of additive gene action and a good scope of selection using their phenotypic performance. Correlation coefficients between grain yield per hill with panicle weight and harvest index significant at 1% level of probability at both level and productive tillers/hill (0.402) and panicle length (0.387) and 1000-grain weight (0.405) showed positive association with grain yield at 5% level of probability at genotypic level, suggested inherent association of these traits to increment grain yield in the advanced lines. In the selection response, among the 32 genotypes PL29 showed highest grain yield and 1000-grain weight compared to the previous generation. The simultaneous character association both at genotypic and phenotypic level and genetic variability panicle weight, fertile grains/panicle and 1000-grain weight along with the advanced lines, PL29 may be included in further breeding to evolve super quality fine rice varieties suitable for our country.