Abstract
Combining ability was studied in five inbred parents and 10 F1 hybrids in upland cotton during 2013-14 at Halani, District Naushehro Feroze, Pakistan. Mean squares due to general (GCA) and specific combining ability (SCA) variances were highly significant for all the fiber traits; which suggested that additive and non-additive gene actions were involved for controlling the traits. The GCA variances were found greater than SCA which revealed predominance of additive genes action for lint index, staple length, fiber fineness and fiber strength, while SCA variances were higher in magnitude than GCA which manifested the involvement of dominance gene action for uniformity ratio. Among the parental cultivars, MNH-886, CIM-506 and CRIS-134 proved as best general combiners for all the fiber traits. Results further suggested that these parental inbreds could be used for crop improvement. As per hybrid combinations, MNH-886 × CIM-506, CRIS-134 × MNH-886 and CRIS-134 × CIM-506 were specific combiners for fiber quality traits which could be exploited for hybrid crop development.
