Genetic Variation of Yam Dioscorea SPP. (Family Dioscoreaceae) Accessions of Sri Lanka

Abstract

The present study determined genetic diversity among seventeen Dtoscorea accessions comprising eleven D. alata, two D, bulbifera, two D. esculenta, one D. pentaphytla and one D. spicafa conserved at the Plant Genetic Resources Center (PGRC), Sri Lanka, Morphologicat analysis \Mas done using 55 standard morphological descriptors of Yarn and, molecular analysis using 15 SSR markers. Statistical analysis for morphological data was done using MINITAB 16, molecular analysis using PowerMarker version 3.25 and MEGA 6.06 software respectively. Results revealed a significant degree of genetic diversity among tested accessions, Five clusters were observed according to the cluster analysis of morphological characterization. A high variation was observed among D" pentaphytta and D" esculenta accessions and rernaining Dioscorea spp. Similarities of morphological characters clustered D. alata accessions with D. bulbifera and D. spicafa. Statistically analyzed molecular data revealed a considerable genetic variation among selected accessions generating a total of 55 alleles with polymorphism in 13 SSR markers. Phylogenetic tree constructed based on Nei's (1983) genetic distance and UPGMA algorithm consists of seven major clusters separating D. alata onto one cluster and other Droscorea spp. into other different clusters revealing no duplicates arnong tested accessions.