Genetic Diversity within Turkish Watermelon [Citrullus lanatus (Thunb.) Matsumura & Nakai] Accessions Revealed by SSR and SRAP Markers

The genetic diversity of Turkish watermelon genotypes selected from the watermelon genetic resource collection was evaluated by SSR (Simple Sequence Repeat) and SRAP (Sequence-Related Amplified Polymorphism) markers. Most of the accessions were collected from various geographical regions of Turkey. Different Citrullus species, wild relatives, foreign landraces, open pollinated (OP) and commercial hybrid cultivars were also assesed for genetic relatedness. Fourteen SSR primers and 31 SRAP primer combinations were used in the experiment. Both SSR markers (100%) and SRAP markers (97.3%) generated high polymorphisms. Based on the SSR and SRAP data, the genetic similarity coefficients were calculated and dendrograms were constructed using the unweighted pair-group method with arithmetic average (UPGMA). Cluster and principle coordinate analyses indicated that, Citrullus lanatus var. lanatus subspecies genotypes, collected from the different regions of Turkey were closely genetically related. Overall our results displayed low genetic variability exists within the Turkish watermelon germplasm in contrast with their considerably high morphological diversity.