Genetic diversity in Vietnamese melon landraces revealed by the analyses of morphological traits and nuclear and cytoplasmic molecular markers

Abstract

Genetic diversity among 59 melon landraces from Vietnam was studied by analyzing morphological traits and molecular markers. The morphological characters of the melon landrace fruits were highly diversified. Among the five types of cultivated melon, "Dua le" and "Dua vang" were classified as Conomon var. makuwa, whereas "Dua gang" was classified as Conomon var. conomon, and "Dua bo" was classified as Momordica. However, "Dua thom" could not be classified into a proper group or variety. The gene diversity based on random amplified polymorphic DNA (RAPD) and single sequence repeat analyses was small and equivalent to that of Chinese Conomon. A cluster analysis revealed that "Dua bo", "Dua le", "Dua vang", and "Dua gang" were grouped in cluster II. Clusters III and IV consisted mainly of Conomon accessions from China and Japan. "Dua thom" was classified into cluster V with landraces from Yunnan Province, China. The comparison of a RAPD profile with 291 melon accessions from Africa and Asia clearly showed that "Dua thom" and Yunnanese landraces were closely related with the small-seed type melons from Myanmar, Bangladesh, and northeastern India. The other four types were related closely with Conomon and Agrestis accessions from China, Korea, and Japan, indicating their involvement in the differentiation and establishment of the Conomon group in East Asia.