The present work assessed the genetic divergence amongst the accessions of vasaka collected from different sub-climatic zones of India by RAPD (Randomly Amplified Polymorphic DNA) using twenty random decamer primers (OPA 1-OPA 20) as the plant was found to enjoyed its therapeutic efficacy in Ayurvedic and traditional system of medicines. The dendrogram constructed for cluster analysis using an un-weighted pair group method with arithmetic means (UPGMA) grouped the accessions into 2 major clusters based on winboot. Out of the twenty random primers used for studying genetic divergence sixteen primers were found to be polymorphic. Out of 20 primers 3 were found to be 100% polymorphic generating a total of 313 amplification products with an average of 19.5 products per polymorphic primer. Genetic relationships among accessions were evaluated by generating a similarity matrix based on Jaccard's co-efficient ranging from 0.60 to 0.91. Results showed that both environmental and genetic factors were effective in observing variations. The degree of genetic variations detected among the accessions of vasaka suggested that RAPD approach seemed to be best suited for assessing with high accuracy the genetic relationships among distinct A. vasica accessions.
Key words: RAPD, Genetic diversity, Adhatoda vasica, variation, Polymorphism, Primer.