Genetic Diversity of some Populations of Watermelon (Citrullus lanatus var. lanatus) Based on Morphological Traits and Microsatellite Markers (ISSR)

For assessing the genetic diversity of Iranian populations of watermelon, 24 local populations together with one foreign cultivar (F-1 hybrid of Sakata Company) were studied using morphological traits and ISSR markers. Populations were grown in field in a randomized complete block design with three replications, and then morphological traits including fruit number in bush, the tallest banch length, fruit weight, fruit diameter and length and rind thickness were measured. Results of analysis of variance showed significant differences among all populations regarding the morphological traits. Cluster analysis based on morphological traits, divided populations in to four groups. In assessment of genetic diversity by molecular markers, ten used primers generated 87 scorable bands, which 75 sites were polymorphic. Polymorphic information content (PIC) of primers varied from 0.52 (marker P4) to 0.91 (marker UBC864) with anaverage of 0.83. Cluster analysis based on Jaccard genetic similarity coefficient, placed populations into seven main clusters. Minimum and maximum genetic distances were observed between populations of Kordestan and Kermanshah and Mazandaran and Khorasan, respectively. Generally the results of this study revealed that ISSR can be efficiently used for assessment of genetic diversity in watermelon populations native to Iran and UBC823 and UBC864 were recognized as the best primers forfiture studies.