Genetic studies of watermelons [Citrullus lanatus (Thunb.) Matsum. & Nakai] sampled from Turkey, the second leading producer, may provide valuable information for breeding and research programs. The objectives of this study were to estimate the level of genetic diversity, population structure, and optimum genome sampling size among the Turkish and several introduced watermelons. | Turkish Journal of Agriculture and Forestry Turk J Agric For (2016) 40: 613-620 © TÜBİTAK doi: Research Article Genetic analyses of Turkish watermelons based on SRAP markers 1 1, 2 1 2 Metin YAĞCIOĞLU , Osman GÜLŞEN *, İlknur SOLMAZ , Halit YETİŞİR , Nebahat SARI 1 Department of Horticulture, Erciyes University, Melikgazi, Kayseri, Turkey 2 Department of Horticulture, Çukurova University, Balcalı, Adana, Turkey Received: Accepted/Published Online: Final Version: Abstract: Genetic studies of watermelons [Citrullus lanatus (Thunb.) Matsum. & Nakai] sampled from Turkey, the second leading producer, may provide valuable information for breeding and research programs. The objectives of this study were to estimate the level of genetic diversity, population structure, and optimum genome sampling size among the Turkish and several introduced watermelons. From the collection, 256 watermelon lines representing all watermelon-growing areas of Turkey along with two accessions of a related genus (Praecitrullus fistulosus (Stocks) Pangalo) and a few popular cultivars were genotyped using sequence-related amplified polymorphism (SRAP) markers. Twenty-seven primers generated 210 molecular markers for genetic analyses. The unweighted pair group method with arithmetic average analysis produced no clear-cut pattern, while principal component analysis indicated three subgroups among the lines studied. They had a narrow genetic base within C. lanatus var. lanatus and were mostly distinguished from each other. Model-based structure analysis indicated that the number of subpopulations in watermelons was four. Among the 258 lines, only 20% (51 lines) had or greater membership coefficients to one subpopulation, and therefore were not admixed. The remaining 207 were admixed by at least two subpopulations. The similarity matrix of genome sampling size of 40 randomly selected .
