Molecular characterization of some cultivated yam (Dioscorea spp.) genotypes in Sierra Leone using simple sequence repeats

The genetic diversity of 52 genotypes of yam germplasm from Sierra Leone was accessed using 14 microsatellite loci. High diversity of 0.650 was noted among genotypes accessed. Mean values of 5.070 and 0.422 were observed for alleles and polymorphic information content respectively. The observed heterozygosity value of 0.788 implies that spontaneous hybridization may have contributed to the ancestry of some genotypes and that improvement by farmers may have possibly been by selection of somatic mutants. The dendrogram of the cluster analysis showed six groups, which also supported groupings and genetic distances explained by the minimum spanning tree. There was no relationship between relatedness of the accessions and their geographical area of origin. The study demonstrated the efficiency of microsatellite markers in separating closely related genotypes within and between species due to their high specificity. This study contributes to an increased understanding of the genetic organization of the collected germplasm.