Heterosis for seed cotton yield and other traits in GMS (Genetic male sterility) based hybrids of Gossypium hirsutum L cotton

摘要

A line x tester analysis was undertaken to estimate the magnitude of heterosis in Gossypium hirsutum for yield, its component traits and fibre quality parameters in 50 GMS (genetic male sterility) based cross combinations. The analysis of variance indicated that the mean squares of genotypes for all the characters were significant indicating the presence of variability among hybrids and their parents. Studies on heterosis revealed that only two cross combinations of GMS 4 x F 1861(30.4%) and GMS 4 xLH 2076 (32.1%) showed positive and significant positive heterosis over the zonal check, CSHH 198 for seed cotton yield. For bolls/plant in GMS 4 x 002 NAH (35.8%), boll weight in GMS 4 x 0238 DA (5.6%), monopods in GMS 16 x Biyani 161, GMS 20 x F 1861 (266.7%), sympods in GMS 4 x RS 810 (22.2%), seed index in GMS 27 x 002 NAH (28.1%) and ginning percentage in GMS 26 x 002 NAH (9.01%) showed the highest and significant positive heterosis over the zonal check, CSHH 198. For quality traits, 2.5 per cent span length and bundle strength the cross combinations of GMS 20 x 005 NAH (9.1%) and GMS 20 x 002 NAH (12.8%) showed the highest heterosis, whereas for maturity coefficient and micronaire value, majority of the crosses showed either non significant or negative heterosis. Thus, the cross combinations of GMS 4 x F 1861 and GMS 4 x LH 2076 can be used for exploitation of heterosis. The female parent, GMS 4 and male parent, 002 NAH recorded significant positive heterosis for most of the characters and the crosses having these parents can be used for development of pure lines.