Assessment of Genetic Diversity and Trait Association in Cotton Genotypes through Multivariate Analysis

Abstract

Genetic diversity plays a vital role in the improvement of cotton yield and fiber quality traits through effective breeding programs. The present study was conducted to evaluate the extent of genetic variability, heritability, and association among important agronomic and fiber quality traits in upland cotton genotypes. Thirty-nine cotton genotypes were assessed during 2013–2014 at Cotton Research Central, Multan, Punjab, Pakistan, using a randomized complete block design (RCBD) with three replications. Data were recorded for oil content, protein content, cellulose content, fiber length, fiber strength, fineness, ginning out turn percentage (G.O.T%), seed index, and seed density. Analysis of variance revealed significant differences among the genotypes for all studied traits, indicating the presence of substantial genetic variability. Genetic parameters including genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), environmental coefficient of variation (ECV), broad-sense heritability (h²), and genetic advance (GA) were estimated to assess the inheritance pattern of the traits. Multivariate analysis through principal component analysis (PCA) demonstrated considerable genetic divergence among the cotton genotypes and identified promising genotypes for future breeding programs. Correlation analysis revealed the degree of association among yield, seed, and fiber quality traits. The findings suggested that traits with high heritability coupled with high genetic advance could be effectively improved through selection, and the identified diverse genotypes may serve as valuable genetic resources for cotton improvement programs.