Combining Ability Analysis for Yield and Fibre Quality Traits in American Cotton (Gossypium hirsutum L.) Genotypes

The present study was conducted with the aim of determining combining ability and variances for different traits and toidentify the best combiners with respect to seed cotton yield and fiber quality. Forty eight F1 hybrids along with parentswere grown in randomized block design with three replications and the data were recorded for 14 characters namely,days to 1st flower, plant height, number of monopodial branch per plant, number of sympodial branch per plant, numberof bolls/plant, boll weight, seed index, ginning out turn lint index, seed cotton yield per plant, uniformity index, fibrestrength, upper half mean length and micronaire value. The variance gca/sca ratio depicted predominance of non-additivegene action for days to first flowering, number of bolls per plant, boll weight, seed index, seed cotton yield per plant,fibres strength, uniformity index, upper half mean length and micronaire value. The characters lint index and numberof monopods per plant revealed non-additive and additive gene action while plant height, number of sympods per plantand ginning out turn were predominantly controlled by additive gene action. The lines H1471, H 1472, H 1522 andH 1098i and the tester C 201 were found best combiners to be considered for future breeding programme. The crosscombination H 1480 × C 201 recorded highest significant SCA effects for seed cotton yield per plant followed byH1098i × C 211 and H 1522 × C210.