Molecular Taxonomy Among Mentha spicata, Mentha longifolia and Ziziphora tenuior Populations using the RAPD Technique

The Random Amplified Polymorphic DNA (RAPD) technique was used to study the molecular taxonomy and genetic relationship between two Mentha species namely, Mentha spicata and Mentha longifolia, and Ziziphora tenuior. Sixteen RAPD primers showing polymorphic bands were used for the construction of the dendrogram and a similarity matrix. A total of 2001 bands were obtained; 419 of them were polymorphic. Similarity values among the studied samples ranged from 0.68 to 0.03. High similarity values were obtained between two samples of Mentha spicata (0.68) collected from local markets and between three samples of Mentha longifolia (0.64) as well. RAPD analysis confirmed that Mentha species are genetically different from Ziziphora tenuior and a genetic variation was found between and within the species tested for this study. The cluster analysis clearly differentiated Mentha spicata and Mentha longifolia from Ziziphora tenuior. Molecular analysis with RAPD markers stressed their ability for differentiation between families, genus, and species of living organisms particularly Mentha species and Ziziphora tenuior.