Discriminating Nigerian ‘Egusi’ melon accessions using agro-morphological and molecular techniques

Abstract

‘Egusi’ melon is an important vegetable crop in the tropics and subtropics that is rich in protein, oils and vitamins. Agro-morphological traits, sequence related amplified polymorphism (SRAP) and simple sequence repeats (SSRs) were used to evaluate 50 accessions of ‘egusi’ melon collected from various parts of the country. The FASTCLUS procedure grouped the accessions into ten distinct groups based on agro-morphological data, with accessions NG/TO/APR/09/029 and A23 characterized by long vines and high seed weight per fruit. A total of 197 bands were scored from 26 SRAP primers, while 49 bands were scored for 25 SSR primers. UPGMA cluster analysis based on dice genetic similarity revealed five and six distinct groups for the SRAP and SSR primers, respectively. A higher level of polymorphism was observed for the SSR primers (93.60%) as compared with the SRAP primers (64.65%), though the discriminating power of the SSR primer (2.28) was lower than that of the SRAP primer (3.71). The relatively higher frequency of SSR polymorphism should be helpful in phylogenetic analysis to better understand these relationships in the melon accessions.

Key words: ‘Egusi’ melon, Agro-morphological traits, SRAP, SSR, Discrimination