Combining ability analysis over environments in Asiatic cotton (Gossypium arboreum L.)

The combining ability studies using line x tester (20 lines and three testers) mating design over six environments for ten characters in Asiatic cotton, revealed that the additive gene effects were predominant for plant height, bolls, seed-cotton, seed, and lint yield/plant, ginning percentage, and seed and lint indices. Nonadditive gene effects were more important for days to flower initiation, whereas both additive and nonadditive gene effects were important for halo length. The best general combiners were: SC 136 and Shyamali for earliness; SD 5 and RG 10 for dwarfness; RG 10 and BH 113 for bolls, seed-cotton, seed and lint yield/plant, and ginning percentage; SD5 and RG 10 for halo length; and RG 8 and K 7 for seed and lint indices. No association was detected between per se performance and sca effects.