Site regression and multivariate analysis for genetic diversity in Gossypium barbadense accessions

Abstract

In India, Gossypium barbadense is cultivated in niche areas in the south and central regions of the country, especially for its quality fibre. Initially, 50 barbadense accessions were screened for their stability across 2 years from the germplasm maintained at ICAR, CICR, RS germplasm, and stable diverse genotypes were selected for further breeding. The results indicated that ICB 262, ICB 174 and ICB 73 were early maturing. ICB 264, CCB 26 and ICB 73 showed tolerance to sucking pests due to their higher trichome density (TD), gossypol glands and epicuticular wax (ECW). G × E interactions were analysed for the 2019–2020 and 2020–2021showed that traits like number of bolls, single plant yield and fibre strength could express better during 2019–2020, single boll weight and micronaire were dominant in season 2. Traits like ginning percentage and fibre length were stable across environments indicating that their expression is genetically controlled. PCA results indicated that about 91.45% of total variability was explained by PCA1, 2 and 3. Diversity analysis grouped the accessions into four major clusters with two sub-clusters in groups 2, 3 and 4, hence forming seven groups. The minimum distance was observed between ICB 176 and CCB 11 (0.56) and the maximum distance was observed between ICB 174 and ICB 1 (3.11).

Keywords

• gossypium barbadense
• diversity
• fibre quality
• stability
• variability