SSR Marker-Based Molecular Diversity and Genetic Characterization of Sesame (Sesamum indicum L.) Germplasm

Sesame (Sesamum indicum L.) is an important oilseed crop, and assessment of its genetic diversity can inform the selection of parental material for crop improvement. This study evaluated molecular variation among 45 sesame genotypes, including two check varieties, using 30 sesame-specific simple sequence repeat (SSR) markers. Genomic DNA was extracted from seven-day-old seedlings, and amplified SSR profiles were assessed for allele number and marker informativeness. Genetic relationships were evaluated using Jaccard’s dissimilarity coefficients and unweighted pair group method with arithmetic mean (UPGMA) clustering. Of the 30 SSR markers examined, 18 (60%) were polymorphic, whereas 12 were monomorphic. The polymorphic loci generated 58 alleles, with two to five alleles per locus and a mean of 3.22. Polymorphism information content values ranged from 0.043 to 0.745, with an overall mean of 0.474. Hs425, Hs635, SiSSM61314 and Si24 showed comparatively high marker informativeness. UPGMA analysis assigned the genotypes to three molecular clusters. Cluster I comprised 36 genotypes, Cluster II contained eight genotypes divided into two subclusters, and Cluster III contained only TPTS-69. The isolated position of TPTS-69 indicated a distinct molecular profile within the marker panel evaluated. The observed allelic variation and clustering patterns provide information for identifying relatively differentiated sesame germplasm and selecting materials for further validation and potential use in breeding programmes.