The following study comprised the combining ability in parental genotypes and the inheritance of yield-related traits in F₁ hybrids of the Pima cotton (Gossypium barbadense L.). The cotton cultivars, Surkhon-9 and Termiz-32, were notably the high-level donor parental genotypes in seed cotton yield and play a vital role in the development of high-yielding cotton cultivars. In all cultivars (σ2si>σ2gi), the dominant role of non-additive variances was evident in managing the seed cotton yield. Study results showed the cultivar Termez-32 can become a donor parent in developing new cultivars with numerous bolls per plant. By comparing the GCA and SCA variances of cotton cultivars, the bolls per plant reflected the control of non-additive genes (σ2si>σ2gi) in cultivars Surkhon-9, Duru Gavhar, and Surkhon-10. In cultivars Termiz-32 and Bukhoro-7, the bolls per plant had the additive genes (σ2si<σ2gi) managing them. Thus, the inheritance of the seed cotton yield per plant and the number of bolls traits occurred mainly with the positive superdominance in the F₁ cross combinations. An outcome of the presented study revealed the development of the new Pima cotton cultivar ‘Guzor.’

Keywords: Pima cotton (G. barbadense L.), cultivars, diallel crosses, combining ability, inheritance, dominance, yield-related traits

Key findings: Results revealed that Pima cotton (G. barbadense L.) cultivars, Termiz-32 and Bukhoro-7, can be desirable for improving the seed cotton yield, while Surkhon-9 and Termiz-32 can be useful for enhancing bolls per plant of cotton. The said breeding material can be beneficial in the development of high-yielding Pima cotton cultivars.