Using a six-parameter model, generation mean analysis was conducted on two interspecific crosses of diploid cotton, GBhv-302 × PA-812 and GBhv-302 × ARBa-1502. To assess the sufficiency of the additive-dominance model, simple scaling tests and joint scaling tests were performed. In one or more of the characters studied, the magnitude of dominant (h) gene action was larger than estimates of additive (d) gene action. Among epistasis, additive × additive (i) kind of gene action was shown to be significant in cross GBhv-302 × PA-812 for 2.5% span length (mm), fiber strength (g/tex) and fibre length uniformity ratio (%); GBhv-302 × ARBa-1502 for fibre fineness (mv). While, the cross GBhv-302 × PA-812 showed significant contribution of dominance × dominance (l) type of gene action for oil percentage. Duplicate type of gene action was reported for all the traits under all cross, except the cross GBhv-302 × ARBa-1502 for the trait 2.5% span length (mm). None of the traits under study exhibited complementary type of gene interaction

diploid cotton, additive, dominance and epitasis gene interactions

All of the experiment's findings show that improving such features in a particular population through heterosis breeding depends on greater estimates of dominant genes. In addition, distinct breeding methods are determined by the forms of epistasis. For instance, a duplication kind of epistasis causes genes to mutual cancelation of each other out, preventing heterosis. Since our main breeding goal is varietal development, both dominant as well as additive component with interallelic interactions should be taken into account. This way, bi-parental mating or reciprocal recurrent selection techniques can break undesired effects

Naghera Y.V., Vavdiya P.A., Mungra K.S. and Prajapati M.R. (2025). Genetic Analysis of Fibre Quality Traits in Interspecific Crosses of Diploid Cotton (Gossypium herbaceum L. × Gossypium arboreum L.). International Journal on Emerging Technologies, 16(1): 172–175