Dekoko is a marginalized, but economically important and endemic cool - season legume crop in Ethiopia. However, the molecular characterization of this crop has not been carried out regardless of its importance as source of protein for the rural poor in Ethiopia. This study is therefore aimed to investigate the genetic diversity and population structure of 83 Dekoko accessions collected from north Ethiopia. Three plants per accession was bulked and Genomic DNA was extracted using CTAB method. Out of the 91 amplified bands using six ISSR primers, 75 (76.92%) are polymorphic. The overall genetic diversity (H) and Shannon’s information index (I) was found 0.185 and 0.293, respectively. This shows a significant of genetic diversity were revealed at species level. Analyses of Molecular Variance (AMOVA) revealed 45% of the significant variation was within populations and 55% was among populations (P < 0.001). Both principal coordinate analysis (PCoA) and unweighted pair group method with arithmetic mean (UPGMA) cluster analysis tends to group the populations in to their own locality and geographic proximity. The dendrogram based on neighbor-joining method and the structure analysis grouped the eight populations into two main clusters in which the first cluster contains only HW population. Overall, our results provide baseline information for genetic conservation and breeding programs of the orphan crop with an important ecological role and food security.

Keywords: Dekoko, Gene flow, Genetic diversity, Genetic structure, ISSR-markers.