Heterosis for seed cotton yield and its contributing characters in cotton (GossypiumhirsutumL.)

A line x tester crossing programme was taken up with ten lines and five testers with a view to identify the best heterotic crosses for seed cotton yield and its attributing traits in upland cotton. The analysis of variance revealed significant differences among genotypes, parents, hybrids and parents Vs hybrids for all the eight traits except parents Vs hybrids for seed index suggesting the presence of considerable amount of genetic variation with respect to various traits studied.Heterosis was worked out over better parent and standard hybrid,G.Cot Hy-12. Based on study of heterobeltiosis, it was found that number of sympodia per plant, number of bolls per plant, boll weight and lint yield per plant were main contributors towards increase in heterotic effects for seed cotton yield per plant. Five crosses viz., G.cot-12 x H 1316 (35.27%), 76 IH 20 x GBHV 170 (33.67%), LRA 5166 x GJHV 503 (24.39%), 76 IH 20 x BS 27 (23.04%) and G.cot-12 x GJHV 460 (20.95%) were best heterotic crosses over standard check for seed cotton yield per plant and could be exploited.