DIVERSITY AND CORRELATION STUDIES OF INTRASPECIFIC HYBRIDS FOR THEIR MORPHOLOGICAL TRAITS IN COTTON (GOSSYPIUM HIRSUTUM L.)

Abstract

The present research aimed to assess genetic diversity in sixty-one crosses concerning yield and yield-related traits. The study also delved into analyzing the associations between these traits. A robust positive and highly significant correlation was observed between plant height and main stem nodes (0.91). Additionally, there was a highly significant positive relationship between the number of squares per plant and both plant height (0.51) and main stem nodes (0.58). The number of flowers exhibited a moderately positive correlation with the number of squares per plant (0.31). In terms of bolls, green bolls showed a high correlation with main stem nodes (0.35) and plant height (0.37), while open bolls (0.38) had a significant impact. Conversely, Cotton leaf curl virus disease exhibited negative correlations with other morphological traits. Genetic diversity among parents forms the foundation of any breeding program and is pivotal for increasing yield. Principal component analysis unveiled a total variance of 53% among crosses, with PC-I contributing 34.3% and PC-II contributing 18.7% of yield-related traits. The number of squares per plant, the number of green bolls, and the number of flowers showed positive significant component loading on the first two factors. Clusters I and II exhibited maximum values for the number of squares, the number of green bolls, the number of flowers, and resistance to cotton leaf curl virus disease. Crosses in cluster II displayed reasonable values for the number of open bolls and the number of flowers but showed susceptibility to cotton leaf curl virus disease. This comprehensive information, derived through the application of various statistical tools, essentially for assessment of diversity in crosses successfully developing an improved breeding program.