Estimation of Gene Action, Heritability and Pattern of Association among Different Yield Related Traits in Upland Cotton

Abstract

A random mating design comprising 6 varieties (FH-142, MS-DK, IUB-63, KZ-189, FB-3159, and VH-300) and F1 crosses was used to check gene action for yield contributing traits in upland cotton.  Heritability and correlation were calculated from F3 populations of the cross CRS-456×Jumbo okra. The randomized complete block design was used in both experiments with three replication at the Department of Plant Breeding and Genetics, University of Agriculture Faisalabad, Pakistan during 2015-2017. In both experiments, analysis of variance indicated significant variation present among the accessions of the upland cotton for all the traits (plant height, sympodial and monopodial branches, nodes number of 1st sympodial branch, height of 1st sympodial branch, bolls per plant, boll weight, lint weight, seed cotton yield, seed index, lint percentage, lint index, seeds per boll, fiber fineness, fiber strength, fiber length and fiber uniformity) under study. Mean values of all genotypes were significantly different from each other for all the traits studied. All the parameters manifested positive correlation with seed cotton yield except plant height, monopodia per plant, nodes number of 1st sympodia, height of 1st sympodia, bolls per plant, seed index and lint index. The inheritance of all the traits in F1 crosses was generally controlled by overdominance gene action except monopodial branches, nodes number of 1st sympodial branch, height of 1st sympodial branches, boll weight, fiber length and fiber uniformity that were partially controlled under additive gene action. Epistasis was not found to be involved in any of the traits. Estimation of broad sense heritability (h2 b. s) in F3 populations were high (60-97%) for all the traits under study. Results suggested form heritability and correlation that these traits can be improved either through appropriate selection method or hybrid breeding programme.