Assessment of molecular diversity in intra-hirsutum genotypes of cotton

In any crop plant species, for development of improved varieties requires presence of large magnitude of genetic diversity among the breeding lines. Molecular characterization of genotypes helps in precise estimation of their genetic relatedness, which can be used by breeders for creating the desired variation. In the present investigation, a set of Fifty two markers covering A and D genome of G. hirsutum were employed to assess the molecular diversity and genetic relationship among 44 intra-hisutum lines, which include a subset of 40 RILs along with parental lines namely RS 2013, PUSA 56-4, standard check LH 2108 and genetic standard TM-1. A total of 263 alleles were detected by 52 primers in the 44 lines with an average of 5.05 alleles per primer. The maximum number of alleles (9) was amplified by NAU3324 and NAU2862 markers. The polymorphism information content (PIC) providing an estimate of discriminatory power of a locus and loci, varied from 0.45 to 0.90 (BNL1421, NAU2722, BNL1421, NAU4898). A dendrogram generated by unweighted pair group with arithmetic mean (UPGMA) revealed the genetic relationships among 44 lines by dividing them into three distinct clusters. Cluster A, B and C represent 23, 11 and 10 lines, respectively. Results reveal the presence of large magnitude of molecular diversity among the studies genotypes.