Studies on genetic parameters, correlation and path analysis in rice (Oryza sativa L.)

Abstract

An experiment was conducted to study the genetic variability in seventy seven rice genotypes for grain yield and its component characters. Analysis of variance revealed the existence of sufficient amount of variability in the material under study. The magnitude of phenotypic coefficient of variation was found to be higher than genotypic coefficient of variation for the characters studied indicated the influence of environment on the manifestation of these characters. The characters such as number of filled grains per panicle and 1000 seed weight exhibited higher estimates of phenotypic and genotypic coefficient of variation indicates that these character could be improved through direct selection. High heritability coupled with high genetic advance was observed for 1000 seed weight, reveals the role of additive gene action controlling this trait. While the trait spikelet fertility (%) is controlled by non-additive gene action and suggesting the improvement of this character through heterosis breeding. The traits such as plant height, number of productive tillers per plant, panicle length, number of filled grains per panicle and spikelet fertility (%) and 1000 seed weight had positive phenotypic and genotypic correlation with grain yield per plant. Path analysis indicated that number of filled grains per panicle and 1000 seed weight exhibited positive direct effects on grain yield at both genotypic and phenotypic level. The characters exhibiting high direct effects for grain yield also exhibited high degree of positive correlation with grain yield. The traits, number of filled grains per panicle and 1000 seed weight could be used as selection criteria for the improvement of grain yield.