MOLECULAR CHARACTERIZATION OF DIOSCOREA VEXANS PRAIN & BURK AN ENDEMIC MEDICINAL PLANT SPECIES OF ANDAMAN ISLANDS USING RAPD MARKERS

Dioscorea vexans Prain & Burk (Family: Dioscoreaceae) is an endemic medicinal plant species of Andaman and Nicobar Islands having anti-fertility properties. Recurrent survey was conducted across 12 locations of South Andaman Islands for characterization of different accessions of Dioscorea vexans using random primers (RAPD markers). The RAPD-PCR profiling was used to assess the variation at genomic level and it resulted in reproducible patterns of amplicons by using specific combination of accession and primers. Among 32 decamer primers used, 18 showed appreciable amplification and all of them were polymorphic in nature. The entries were grouped into two major groups having variation of 95% in between them. UPGMA analysis revealed that the accessions from Sippighat and Port Mout showed maximum similarity of 36%. Accession from Chidiyatapu was found distinct from other samples showing 99% variation from others. The primers used in this study could clearly demarcate the entries into well-defined distinct groups as there was at least 64% variation among all the collected accessions. Though the collected accessions were morphologically similar, yet they were found to be different from each other as revealed by decamer primers from the clustering pattern. The study reveals that RAPD is an efficient and cheap tool, easy to handle and reliable molecular marker in finding out the genetic diversity in Dioscorea vexans, which will be useful in future conservation measures to protect this rare and endemic medicinal plant as well as other such species.