Vegetos

Abstract

Present investigation was carried out to estimate general combining ability of the parents and specific combining ability of hybrids for the development of high yielding and better quality cultivars i.e. nineteen parents’ viz. 15 lines and 4 testers in line x tester mating design. GCA is associated with additive genetic effects, whereas SCA is taken as the measure of non-additive type of gene actions. GCA is attributed to additive and additive gene effects epistasis and is theoretically fixable; on the other hand SCA attributed to non-additive gene action due to dominance or epistasis or both and is non-fixable. The presence of non-additive genetic variance is the primary reason for initiating any hybrid programme. GCA variance (σ2gca) was invariably lower than SCA variance (σ2sca) for almost all characters indicating preponderance of non-additive gene action. The studies on general combining ability of parents revealed that the lines H1442 was a good general combiner for seed cotton yield, number of bolls per plant, boll weight, number of monopodia per plant and plant height. Among the testers, H1098-i was a good general combiner for seed cotton yield, number of bolls per plant and boll weight. The crosses RS875 × H1098-i (33.44), H1316 × H1236 (31.04) and LH2306 X H1098-i (27.14) exhibited positive significant specific combining ability effects for number of bolls per plant, boll weight and seed cotton yield per plant.