Genetic diversity of some peanut cultivars based on SSR and rapd molecular markers in Vietnam

Abstract

RAPD and SSR markers have been used for analyzing the genetic diversity of 30 individuals of different peanut varieties collected from different geographical locations in Vietnam. Analysis of PCR products of 26 RAPD primers showed a total of 273 amplified fragments, 235 fragments of them were polymorphic. On the other hand, SSR markers analysis cleared that there were 44 alleles resulting from 12 SSR primer pairs, 38 alleles of them were polymorphic. Phylogenetic analysis proved the genetic similarity and relationship between the 30 peanut individuals analyzed. Genetic similarity ranged from 0.660 between L14 - QNGAI and L14-L20 to 0.881% between DU-L27 and LDH09-L19066 base on RAPD and SSR markers. The observed number of alleles (na), effective alleles (ne), Nei’s gene diversity (h) and Shannon’s information index (I) were observed at the individuals level as 1.868, 1.395, 0.239 and 0.371 respectively. These results showed the abundant genetic variability in the individuals of different peanut varieties. Nei’s gene diversity investigation showed that genetic diversity was mainly found within geographical populations. The results of UPGMA analysis showed that geographical isolation is an important factor in the observed genetic differentiation. A similarity tree based on the combination between RAPD and SSR shows that two main clusters, the first main cluster contained L14 and LACDOBG while the second contained the remaining twenty eight Peanut cultivars. Phylogenetic analysis showed the genetic distance and the genetic similarity among the 30 Peanut cultivars. These results may be due to the origin of the cultivars and all peanut cultivars may result from the true species peanut and its inter-hybridization.