COMBINING ABILITY AND HETEROSIS STUDIES IN UPLAND COTTON (GOSSYPIUM HIRSUTUM L.)

Abstract

Cotton is Pakistan's most important fiber crop and the country's economic lifeline. It is an important agricultural commodity in Pakistan, providing a source of income for farmers as well as raw materials for the textile industry. Farmers and the textile industry are also looking for ways to improve fiber quality and increase seed cotton production. Given the low yield pattern and growing demand of the textile industry, the breeding programs need to be planned as a breeder to increase cotton production in the region. Knowledge about inheritance mechanisms, heterosis, and the ability of different characters to combine is crucial for this reason. The most challenging task for plant breeders in any hybridization program is finding the best combination of two (or more) parental genotypes to optimize variation within similar breeding populations, and therefore the possibility of detecting superior transgressive segregants in the segregating populations. After its introduction in 1942, the combining capacity has been commonly used in plant breeding to evaluate the performances of lines in hybrid combinations. Heterosis (also known as hybrid vigor) is a natural occurrence in which hybrid offspring of genetically diverse individuals have enhanced physical and functional characteristics compared to their ancestors. For nearly a century, heterosis has been increasingly used in crop development with the aim of producing more vigorous, higher yielding, and better performing cultivars. A short analysis of previous studies on cotton combining ability and heterotic effect estimation has been provided in this paper. This will strengthen our existing understanding of plant breeding's combining ability and heterosis, as well as recent research advances in this field.