GENETIC DIVERSITY IN GOSSYPIUM HIRSUTUM (L.) FOR COTTON LEAF CURL DISEASE IN ASSOCIATION WITH AGRONOMIC AND FIBER TRAITS

Abstract

Knowledge of genetic diversity in terms of resistance or susceptibility to cotton leaf curl disease (CLCuD) and the agronomic value of economically important traits are essential. This is also required before starting a breeding program to develop disease resistant varieties. Germplasm comprising of 17 conventional cotton (Gossypium hirsutum L.) genotypes were screened under field conditions for the evaluation of resistance against CLCuD in addition yield and fiber quality traits were also measured. Disease scores revealed that none of the varieties were resistant to CLCuD. CIM-615, MARVI, and CIM-616 were tolerant to moderately tolerant while the S-12 genotype was highly susceptible to the disease. These three most tolerant genotypes, CIM-615, CIM-608 and CIM-616 had the highest metroglyph scores resulting from taller, higher yielding plants with stronger and more uniform fibers. Using the metroglyph analysis, these 17 genotypes were separated into seven groups. The separation of these genotypes into groups indicated the presence of genetic diversity, and superior parents from different groups that could be utilized for pyramiding genes governing yield and fiber related traits in addition to the disease tolerance into a single cotton genotype.