Genetic diversity of chinese thin-skinned melon cultivars (Cucumis melo L.) based on simple sequence repeat markers

Genetic diversity among 46 Chinese thin-skinned melon cultivars (Cucumis melo L. 2n=2x=24) of diverse origin was assessed using 50 simple sequence repeat (SSR) markers. Thirty of 48 primers amplified polymorphisms, where 179 bands (similar to 4 bands per SSR primer) defined the genotypes studied. Forty-six accessions were partitioned into nine groups using multidimensional scaling (MDS) and cluster tree analysis. Twenty-one of the 46 accessions were selected from these nine groups for repeated analyses. There was no difference between MDS and cluster analysis using these nine and all accessions (46) indicating that both multivariate approaches Were effective in describing genetic relationships among the accessions examined. Moreover, the data indicated that genetic diversity of the Chinese thin-skinned melon cultivars examined could be enhanced by the introduction of genetic variation from Chinese accessions of different origins. Additionally, it would be advantageous to acquire more accessions from geographically varied regions to ensure the retention of existing genetic diversity in China.