Assessment of genetic variation among populations of Rhynchostylis retusa, an epiphytic orchid from Goa, India using ISSR and RAPD markers

Abstract

Rhynchostylis retusa (L.) Bl., a monopodial epiphytic orchid species with attractive flowers arranged in racemose inflorescence, ranks among the important Indian ornamental orchids. Comparative population studies using PCR based markers, RAPD and ISSR, were performed to assess the genetic diversity of the wild orchid. Among the 35 primers tested, 13 RAPD and 7 ISSR primers were selected for the analysis. In total, 74 RAPD and 30 ISSR fragments were generated. High level of polymorphism was recorded in RAPD (76.13 percent) than ISSR (62.6 percent).In case of RAPD, Nei's average genetic identities value for different populations of R. retusa ranged from 0.405 to 0.932. While for ISSR, it ranged from 0.733 to 0.933. The results of the present study can be seen as starting point for future research on the population and evolutionary genetics of this species.