Abstract:To provide theoretical basis for effective use of melon germplasm resources, we studied the genetic relationship and diversity of melon with different degree of salt tolerance. In this study, the genetic diversity of melon germplasm resources was analyzed by SequenceRelated Amplified Polymorphism (SRAP) using 27 melon varieties with different salt tolerance levels. 24 primer pairs with clear amplification and rich polymorphism were selected from 364 pairs, and 415 clear sites were amplified totally, of which 241 were polymorphic sites and the polymorphic ratio was 58%. Average observed number of alleles (Na) was 1.588 0, average effective number of alleles (Ne) was 1.347 0, average Neis gene diversity (H) was 0.201 3, average Shannons information index (I) was 0.301 0, and the results showed that melon germplasms had abundant genetic diversity. Unweighted pairgroup method with arithmetic means (UPGMA) clustering results showed that the genetic similarity coefficients were between 0.36 and 1.00. 27 melon varieties were divided into four classes at the genetic similarity coefficient of 0.72. Salt tolerant melon was distributed among three categories, medium salt tolerant melon was distributed through all the classes, and while salt sensitive melon was concentrated in the first group, the results demonstrated that genetic diversity of salt tolerant and medium salt tolerant melon were more abundant than that of salt sensitive melon. Cophenetic matrix correlation coefficient of genetic similarity coefficient and UPGMA clustering result was 0.749, which indicated that the cluster analysis was accurate. The study indicated that the genetic diversity of salt tolerant melon was rich, and in order to get salt tolerant heterosis varieties, more far genetic relationship germplasms need to be introduced.