This study aimed to evaluate the inheritance patterns, heterosis, and phenotypic variability among the F₁ and F₂ populations for key morpho-agronomic traits in medium-staple cotton (Gossypium hirsutum L.). Six parental genotypes and their 30 F₁ and F₂ diallel hybrids received evaluation through plant height and fruiting branch number. Several F₁ hybrids showed considerable positive heterosis, while F₂ populations displayed expanded phenotypic variability and moderate-to-high heritability, revealing stable transmission of favorable traits. High heritability and superior performance were particularly notable in cross combinations such as Yulduz × T-1391, Niso × T-1336, and Guliston × Niso. These hybrids, therefore, became recommendable as promising breeding material for improving yield components and earliness in medium-staple cotton. The study revealed positive overdominance for plant height in 10 hybrid combinations, while heritability ranged from 0.40 to 0.71 for plant height and from 0.53 to 0.87 for fruiting branches. The identification of significant variation and heterotic effects was successful across hybrid populations, indicating strong breeding potential.
Cotton (G. hirsutum L.), F₁ and F₂ populations, plant height, fruiting branches, heterosis, inheritance, genetic variability
The cotton (G. hirsutum L.) hybrids Niso × Yulduz, Niso × Guliston, Yulduz × T-1336, and Yulduz × T-1391 consistently showed superior performance for plant height and the number of fruiting branches. Therefore, these promising combinations can be a desirable source for improving yield and earliness in medium-staple cotton.treatment 6 mM L-1 concentration notably enhanced the grain and oil yields and carbohydrates.