Evaluation of genetic variability parameters for yield, yield attributes and fibre quality traits in the F2 population of Gossypium hirsutum L.

The F2 populations of the crossings CO 14 × NDLH 1938 and CO17 × NDLH 1755 were used to investigate variability and heritability studies in order to better understand the gene action involved in each characteristic studied. Morphological data viz., days to first flowering, plant height (cm), number of sympodials, number of bolls per plant, boll weight (g), ginning outturn (%), upper half mean length (mm), elongation percentage (%) and micronaire value (µg/inch) were all recorded in each plant of both the populations. Studies of heritability and genetic advance as a percent of mean help us determine if a gene is additive or epistatic in nature, and so undergo appropriate breeding programmes for population enhancement. The value of PCV (Phenotypic Coefficient of variation) was always greater than GCV (Genotypic coefficient of variation) indicating the environment also plays a major role in contributing to the variations. The seed cotton yield per plant alone was shown to exhibit additive gene action with high heritability and strong genetic advance as percent of mean, suggesting that it might be used in direct selection since it is the most important attribute for population development.