Genetic relationship and polymorphism of selected medicinal plants of Asclepiadaceae using RAPD molecular analysis method

Abstract

Present study was aimed to assess the genetic similarity among the medicinal plants of Asclepiadaceae family members such as Ceropegia juncea, Gymnema sylvestre, Oxystelma esculentum, Pentatropis capensis and Wattakaka volubilis , by using RAPD based molecular analysis. Sixteen primers (OPA, OPC, OPF and OPG series) were used to screen the genetic variation between the selected Ascleipidaceae members. RAPD analysis revealed the presence of 936 bands in which 466 were monomorphic and 256 were polymorphic bands. In particular, 49.78% were monomorphic and 27.35% were polymorphic with an average of 16% polymorphism per primer from the 936 amplified products. The highest number of bands was observed in Ceropegia juncea (198) followed by Pentatropis capensis (190), Oxystelma esculentum (189), Gymnema sylvestre (182) and Wattakaka volubilis (177). Among the primers used OPC 05 (17 bands), OPC 16 (17 bands) and OPC 03 (18 bands) produced maximum number of bands in Wattakaka volubilis , Pentatropis capensis and Gymnema sylvestre respectively. UPGMA cluster analysis revealed that presence of Wattakaka volubilis and Gymnema sylvestre in a same cluster (cluster 1) and Pentatropis capensis and Oxystelma esculentum in same cluster (cluster 2) had close relationship with each other. Findings revealed that presence of Ceropegia juncea in separate sub cluster (2) clearly evidences that species is so distant from other species of Asclepiadaceae. It may be concluded that RAPD tool will be very much helpful for the taxonomist to identify the plant members and place them in the appropriate family through molecular data.