Genetic relationship among East and South Asian melon (Cucumis melo L.) revealed by AFLP analysis

Ninety-nine accessions of melon (Cucumis melo L.) mainly from East and South Asia were analyzed based on the polymorphism of 210 amplified fragment length polymorphism (AFLP) bands to reveal the genetic structure and phylogenetic relationship in Asian melon. A cluster analysis based on their genetic similarity revealed three major clusters, i.e., a vars. makuwa and conomon group, a small-seed type group and a group of Japanese F-1 cultivars and large-seed type accessions. Most of the East Asian melon accessions classified into the first group were of the small-seed type with a seed length shorter than 9.0 mm. The varieties of C. melo were roughly divided into two groups by a principal co-ordinate analysis based on AFLP data, that is, the group of vars. makuwa and conomon and small-seed type melon and the group of var. reticulatus and large-seed type melon. Indian melon accessions were rich in genetic variation. Melon accessions closely related to vars. makuwa and conomon were found in east India, and they were considered as possible candidates of the prototype of vars. makuwa and conomon.