GENETIC ANALYSIS OF CHARACTER ASSOCIATION FOR POLYGENIC TRAITS IN SOME RECOMBINANT INBRED LINES (RIL’S) OF RICE (Oryza sativa L.)

Abstract

Fourteen recombinant inbred lines (RIL’s) obtained from IR 30 and Basmati 370 were evaluated along with two popular varieties viz. Khitish (IET4094) and Minikit (IET 4786) for 14 biometrical characters during summer 2012 at Regional Research Station, New alluvial Zone, Chakadaha, Nadia, Bidhan Chandra KrishiVishwavidyalaya, Mohanpur, West Bengal, India., in Randomized Block Design with two replications. Except number of primary branches per panicle, grain breadth and kernel breadth all the characters studied showed significant differences among the genotypes. Four lines (S7, S10, S13 and S14) possessed significantly higher grain yield than superior check variety. The high estimates of GCV and PCV were obtained for number of panicle per plant, grain yield per plant, floret number per panicle, number of grains per panicle and panicle weight. High heritability was observed for number of panicle per plant, kernel L/B ratio, kernel length, 1000 grain weight and grain L/B ratio. High genetic advance was observed for number of grain per panicle, floret number per panicle, grain yield per plant, number of secondary branches per panicle and 1000 grain weight respectively while lowest genetic advance was observed in kernel breadth. Genetic advance as percentage of mean was highest for number of panicle per plant followed by grain yield per plant, florets number per panicle and Kernel L/B ratio while lowest was recorded for kernel breadth. High heritability coupled with high genetic advance was obtained for number of grains per panicle, 1000 grain weight, kernel length and grain yield per plant. It indicated the predominance of additive gene action for controlling these characters. Therefore, these characters can be improved simply through selection. High heritability associated with low genetic advance was observed for panicle weight, grain length, grain L/B ratio and kernel L/B ratio. It suggested non–additive gene action for the expressions of these characters. The magnitude of genotypic correlation coefficient was in general higher than that of the corresponding phenotypic ones. Grain yield per plant was significantly positively correlated with number of panicles per plant, floret number per panicle and number of grain per panicle. The kernel length imparted the highest positive direct effect on grain yield per plant followed by number of grain per panicle, number of panicle per plant and panicle weight. Keyword: recombinant inbred lines (RIL’s), correlation, genetic advance, heritability and path coefficient.