Genetic studies in colour-cotton (Gossypium hirsutum L.) genotypes for seed cotton yield and fibre quality traits

Abstract

The success of plant breeding depends on the existence of genetic variability present in the experimental material. Assessment of the extent and distribution of genetic variation in a crop species is essential in establishing the pattern of diversity and evolutionary relationships. We evaluated 240 colour-cotton genotypes of varying shades of brown and green lint with five white genotypes as checks during Kharif 2016 in Agricultural Research Station, Dharwad Farm, University of Agricultural Sciences, Dharwad using an augmented design. Analysis of variance indicated that there was a significant variation in the experimental material. Ample variability was observed in the experimental material studied for all the characters. Fibre colour exhibited high values of PCV, GCV, heritability and genetic advance as per cent of mean (GAM). It indicated that there was less influence of environment on the expression of colour and selection can be effective based on this trait. Whereas, fibre strength and length exhibited low PCV and GCV values, low heritability coupled with low genetic advance indicating a greater influence of environment on the fibre traits and thus may show low response to selection. Most of the traits studied were negatively associated with the fibre colour indicating the difficulty in the improvement of fibre colour along with other yield-related traits. It is challenging to break the negative association of these traits by transgressive breeding approaches to select for transgressive segregants with high yield along with good fibre colour.

Keywords

• colour-cotton
• variability
• fibre colour