Combining ability analysis for yield and fibre quality traits in intraspecific hybrids of Gossypium hirsutum L

Line x tester analysis was carried out involving six lines and 4 testers for seed cotton yield, yield contributing traits and fibre quality traits for estimation of combining ability effects of parents for sixteen characters. The analysis of combining ability revealed that the variance for SCA were larger than GCA except uniformity ratio which corresponds with non- additive gene action which can be improved by heterosis breeding. Based on the high per se performance and high gca effect, the parents C 10-8 and RAHC 1917 were considered as best general combiner for boll weight and single plant yield per plant. Regarding boll weight, TCH 1822 and C 10-8 were good general combiners with significantly high per se performance. These parents were found to be recorded as good general combiners for different characters. Hence, these can be used in recombination breeding to obtain more favorable gene recombinations for seed cotton yield. The cross TCH 1819 x RS 2821 showed a positive and significant sca effect for the number of bolls, boll weight and seed cotton yield. The cross Anjali x CPD 1501 showed a positive and significant sca effect for boll weight, lint index, seed index and seed cotton yield. The cross TCH 1926 x RS 2821 exhibited a positive significant sca for the number of bolls, 2.5 % span length and fibre strength. The non – additive gene action has played an important role in expression of seed cotton yield and its component traits which justify the heterosis breeding and its exploitation commercially.