Combining ability and heterosis for yield contributing and fibre quality traits in the hybrids of Gossypium hirsutum L.

Abstract

The present study was investigated in thirty five hybrids of Gossypium hirsutum L. for combining ability and heterosis for ten yield and fibre contributing traits. These hybrids were obtained by the crosses made between seven lines and five testers. None of the crosses was superior for all the traits studied for the mean performance. The hybrid TCH 1199 × GTHV 323 showed the highest mid and better parent heterosis for the lint index and the hybrid TCH 1828 × RHC 1409 exhibited the highest significant mid and better parent heterosis for ginning outturn. The characters viz., boll weight and single cotton yield per plant were identified to have the highest significant mid and better parent values in the hybrid BSH 18 × RHC 1409. For yield contributing traits viz., the number of sympodial branches per plant and the number of bolls per plant out numbered in the hybrid CO 14 × KC 3 with the maximum standard heterosis among the thirty five hybrids. Combining ability analysis exhibits the dominance of non-additive gene action in all yield and fibre quality contributing traits. Among the lines CO 14 and TCH 1828 were estimated as the best combiners for yield and quality traits, respectively. Among the testers, KC 2 and KC 3 were found to be the best among all the five testers. The hybrid BSH 18× RHC 1409 exhibited the highest sca for the boll weight and seed cotton yield per plant and the hybrid BSH 18 × GISV 323 exhibited the highest sca for the quality traits viz., ginning out turn and upper half mean length; TCH 1828 × KC 3 and CO 14 × KC 2 best performed hybrids for sca values for the quality traits viz., elongation length and micronaire values.