Genetic relationship among grape (Vitis vinifera L.) genotypes grown in inner Anatolia region Turkey analyzed by ISSR and RAPD markers

Grapevine (Vitis vinifera L.) is extensively cultivated in Turkey and holds significant cultural and economic value. However, genetic characterization of grape genotypes from lesser-studied regions such as Inner Anatolia remains incomplete, limiting conservation and breeding efforts. This study addresses this critical knowledge gap by utilizing ISSR (inter simple sequence repeats) and RAPD (randomly amplified polymorphic DNA) molecular markers to comprehensively assess genetic diversity and relationships among grape genotypes from the Divriği district in Sivas province, Turkey. Eight ISSR and eight RAPD primers were used, revealing considerable genetic variation. The ISSR primers produced a total of 88 polymorphic bands, with primer UBC-810 producing the highest number of bands (15). Similarly, RAPD primers generated 68 polymorphic bands and the highest number of bands (13) were produced by OPA-18 marker. The UPGMA dendrogram analysis using ISSR data revealed two primary genetic clades, with similarity indices between 0.212 and 0.816. Similarly, RAPD analysis also produced two main clusters, exhibiting genetic similarity indices between 0.164 and 0.912. Principal component analysis (PCA) corroborated the dendrogram groupings from both ISSR and RAPD analyses, exhibiting consistent clustering and strengthening the dependability of both marker systems. Significant genetic differentiation was observed among the tested grape genotypes, highlighting the presence of genetically distinct individuals. Genotypes 'G7', 'G1', 'G9', and 'G10' demonstrated significant genetic divergence, suggesting them as crucial candidates for conservation efforts. This genetic diversity likely reflects historical cultivation practices, natural selection, mutation accumulation, and potential introgression from wild populations. The results indicate the significance of integrating molecular markers into grapevine breeding and conservation efforts. Both ISSR and RAPD markers proved successful in genetic characterization, yielding significant insights into grapevine genetic resources. These findings are essential for sustainable viticulture practices, the preservation of genetic diversity, and future grapevine improvement initiatives in Turkey.