Assessment of genetic diversity for cotton leaf curl virus (CLCuD), fiber quality and some morphological traits using different statistical procedures in Gossypium hirsutum L

Abstract

Cotton leaf curl virus disease (CLCuD) is one of the major factors limiting cotton production in Pakistan. For the assessment of genetic diversity one hundred cotton genotypes was evaluated for CLCuD tolerance, fiber quality, yield and some yield related traits. For evaluation of these traits cluster, principle components (PC) and correlation analysis were employed to obtain suitable parents that can be further exploited in a breeding programme. CLCuD exhibited negative and significant association with seed cotton yield (-0.317**) while with other traits it showed non-significant correlation. The ginning out turn had a significant positive correlation (0.367**) with fiber fineness but negative and significant association (-0.273**) with fiber length. For staple length only positive and significant association was found with sympodia per plant (0.210**). Plant height showed positive association (0.661**) with sympodia per plant and seed cotton yield (0.233*) while sympodia per plant showed positive and significant association with seed cotton yield (0.271**). Principal component (PC) analysis showed first 5 PCs having eigen value >1 explaining 71.3% of the total variation with plant height, sympodia per plant and seed cotton yield being the most important characters in PC1. Cluster analysis classified 100 accessions into four divergent groups. In cluster 3 and 4 included genotypes with higher tolerance of CLCuD and better fiber quality along with higher yield potential were included. Scatter plot and tree diagrams demonstrated sufficient diversity among the cotton accession for various traits and some extent of association between different clusters. The results concluded that the diversity among the genotypes could be utilized for the development of CLCuD resistant varieties with higher lint yield and germplasm conservation programs aimed at improving CLCuD tolerance with better fiber quality.