Genetic variability of Asiatic cotton (Gossypium arboreum L.) germplasm for yield and surgical cotton properties

Diploid cotton (Gossypium herbaceum and G. arboreum) is well known for its great resistance to biotic and abiotic stresses. Additionally, their short staple and coarse fibre characteristics make them ideal for medical cotton applications. Despite these benefits, the cultivable area under diploid cotton has decreased recently, and limited breeding efforts have been taken to develop cultivars suitable for the surgical cotton industry. Therefore, the identification of promising genotypes is very important for the development of diploid cotton varieties with high yield and superior fibre quality. In this study, 150 G. arboreum genotypes and five check varieties were evaluated for 17 yield and fiber quality traits to determine the level of genetic variability and usefulness for surgical cotton properties. Genetic variability analysis revealed high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) for plant height, number of monopodia, single plant yield and lint index. High heritability (H) coupled with high genetic advance (GA) was observed for plant height, number of nodes, number of bolls, number of monopodia, boll weight, single plant yield, lint index and 2.5 % span length. Principal component analysis of 17 quantitative traits indicated that the first five principal components (PC) contributed 71.53 % of total variation, with important yield attributing traits were present in PC1 and PC3, while important fibre quality traits were reported in PC2. The genetic diversity analysis revealed that the 155 cotton genotypes were classified into five clusters, with Cluster IV having the most genotypes (81). Based on 2.5 % span length and micronaire data, a surgical cotton reference set was constituted. The analysis of surgical cotton parameters suggested that three genotypes namely Phule Dhanwantri, CNA1039 and FDX231 had excellent absorbent cotton properties in combination with higher yield attributes. Future exploitation of the identified genotypes could increase Asiatic cotton productivity and surgical cotton quality.