Estimation of heterobeltiosis and standard heterosis for seed cotton yield and its component traits in upland cotton (Gossypium hirsutum L.)

A diallel analysis was designed aiming towards the identification of best heterotic crosses for seed cotton yield and its component traits in upland cotton (Gossypium hirsutum L.). The present study was conducted at Cotton Research Station, Junagadh Agricultural University, Junagadh during kharif 2017 in a randomized block design with three replications. Forty five crosses obtained by crossing 10 x 10 half diallel were evaluated for 6 biometric traits with their parents and check (GN.Cot.Hy-14). The analysis of variance revealed significant differences among the mean squares due to genotypes, parents, hybrids and parents Vs hybrids for all the characters except parents Vs hybrids for days to 50 per cent boll bursting, plant height and seed index suggesting the presence of considerable amount of genetic variability among the parents and the material which was most useful for the study of manifestation of heterosis and genetic parameters involved in the inheritance of different traits studied. Based on study of heterobeltiosis, it was found that number of sympodia per plant and numbers of bolls per plant were main contributors towards increase in heterotic effects for seed cotton yield per plant. Four crosses viz., GJHV-503 x GJHV-515, GISV-267 x GJHV-517, GJHV-517 x GJHV-522 and GJC-101 x Deviraj were best heterotic crosses over standard check for seed cotton yield per plant. These cross combination may utilize for further improvement to develop high yielding genotypes after due testing.