Variability studies in F2 population of upland cotton (Gossypium hirsutum L.) for quantitative and qualitative traits

Abstract

The present investigation on F2 population of TCH 1828 X GTHV 15-34, CO 14 X GISV 323, CO 14 X RHC 1409 and CO 17 X KC 3 were used for the variability studies thereby identifying the phenotypic (PCV), genotypic variations (GCV), heritability (h2) and genetic advance as percent of mean (GAM) present in the population. Heritability and genetic advance are crucial selection criteria. Heritability estimates combined with genetic advance are usually more accurate in forecasting gain under selection than heritability estimates. Seed cotton yield per plant was observed to have additive gene action, high heritability, and high genetic advance as a percent of mean, therefore it may be chosen as the essential feature for population growth among all the traits evaluated in all the crosses under study. The crosses TCH 1828 X GTHV 15-34 and CO 14 X RHC 1409 for the trait, number of bolls per plant and the cross TCH 1828 X GTHV 15-34 for the trait, boll weight per plant also had high heritability and high genetic advance as percent of mean hence additive in nature hence could be taken for direct selection for the improvement of the population. All other traits studied were found to contribute non-additive or epistatic gene action, hence heterosis breeding could be performed for the enhancement of the population for these traits. Key words: GCV, PCV, heritability, GAM, G. hirsutum L., variability studies, F2 population