Determination of Genetic Divergence Pattern of White Fly Resistant Cotton Cultivars by Using Microsatellite

Cotton is considered a cash crop in the agriculture sector, and whitefly infestation is one of the cotton crop's significant biotic stresses. This study aimed to identify whitefly Bemisia tabaci resistant cotton varieties that can be incorporated into a cotton breeding program to improve the cotton crop's quality, yield, and growth. In this study, we used 10 Microsatellite (SSR) markers for genetic diversity assessment among 50 genotypes of G. hirsutum. 58 loci were found by applying the NAU and BNL series primers. A maximum number of loci, eight, were amplified by SSR markers NAU-883, NAU-2714, and BNL-827, respectively. SSR marker JESPER-101 amplified a minimum number of the loci,i.e., 2. The PIC count ranged from 0.7215 to 0.8828, with a mean value of 0.4034. NAU 2161 displayed a maximum polymorphism value of 0.8828 and BNL 1672 showed a minimum polymorphism value of 0.4034. Cluster analysis grouped the 50 genotypes into four clusters. Cluster A holds 30 varieties. Cluster B includes 11 varieties. Cluster C had six varieties, and cluster D had 3. Genetic diversity is maximum in varieties NS-161, VH-307, and AGC-555, as they are located at the most significant distance in clusters. The SSR genetic profile for every cultivar made it conceivable to separate a few cultivars.

To conclude, this investigation of the genetic divergence of cotton cultivars with SSR markers supports the need to bring new alleles into the genetic pool of the cultivars. It can help in assessing the best whitefly-resistant cotton variety. The information generated from diversity analysis studies will help in future breeding plans for improving the hereditary variety of cotton cultivars to fulfill the need for cotton development for various purposes.