Components of genetic variation and graphicalanalysis (VR-WR) for some yield and quality characters in Basmati rice (Oryza sativa L.)

Abstract

Gene action for eight yield and six quality traits were evaluated through Hayman’s analysis (graphical and component) for fifteen direct F1 hybrids along with their six parents of Basmati rice were studied in a randomized complete block design with three replications. Significant differences were observed among parents, hybrids and hybrids versus parents for most of the agronomic, yield and quality characters of hybrids. Valid graphical analysis were explained for characters like plant height, 100 grain weight, days to 50% flowering, days to maturity, kernel length before and after cooking and alkali spread value, showing significant deviation of regression coefficient, ‘b’ from zero and non significant deviation of ‘b’ from unity and all these traits revealed over dominance type of intra allelic interaction. Furthermore, component analysis were done for all the traits by examining estimates D, F, H1, H2, h2 and E and proportion of components i.e. (H1/D)0.5 , H2/4H1, KD/KR, h2/ H2 and h2n. The component D, reflecting additive genetic variance was significant for all the characters studied except for effective tillers per plant, seeds per panicle, grain yield per plant, kernel breadth after cooking and amylose content. The ratio (H1/D)0.5 which measured the mean degrees of dominance over all loci was more than one indicating over dominance for all the characters. The ratio, H2/4H1, close to 0.25 for characters effective tillers per plant, panicle length, grain yield per plant, kernel breadth, amylose content indicating nearly symmetrical distribution of positive and negative alleles at loci showing dominance for the traits. Likewise, ratios, KD/KR and h2/H2 revealed presence of dominant genes/group of genes for different traits. Heritability in narrow sense (h2n), more than 50% for Plant Height, Seed per panicle, Kernel length and Kernel Length After cooking indicated major part of additive gene action in phenotypic variability and selection should be effective for improvement of these characters in rice. © 2019 Plant Archives. All rights reserved.