GENETIC INHERITANCE AND VARIABILITY OF MAIN STEM HEIGHT IN F1 HYBRIDS OF GOSSYPIUM HIRSUTUM L. UNDER OPTIMAL AND WATER-DEFICIT CONDITIONS

Аннотация

In this study, one of the synthetic selection methods — biparental hybridization — was used to improve drought tolerance in varieties and lines belonging to Gossypium hirsutum L. The inheritance and variability of the morphological trait "main stem height" in F1 hybrids obtained through biparental crosses were studied under both optimal irrigation and water-deficit conditions. The results showed that under optimal irrigation, certain maternal genotypes (Saenr-Pena-85, Catamarca-811) and paternal genotypes (C-6580) exhibited higher stem height values compared to the standard variety (C-6524). Among the F1 hybrids, no combinations exceeded their parental forms in terms of stem height. However, under water-deficit conditions, some hybrids (e.g., F1 C-6580 × Saenr Pena-85, F1 C-6580 × Acala-40) demonstrated superior performance compared to both parents. Analysis of the dominance index (hp) revealed incomplete dominance, negative and positive heterosis among the F1 combinations. Particularly, the hybrids F1 Sulton × Saenr Pena-85, F1 Sulton × Hapicala-19, F1 C-6580 × Acala-40, and F1 Nam-77 × Acala-40 showed positive heterosis, indicating their potential for further selection and breeding programs.