ISSR marker assisted genetic diversity assessment in natural populations of two endemic orchids Aerides multiflora and Rhynchostylis retusa from Uttarakhand, India

Aim of the study was to analyze genetic variability among natural populations of two endemic orchids (Aerides multiflora and Rhynchostylis retusa) of Uttarakhand, India using inter-simple sequence repeat (ISSR) makers. Both the species, known for their ornamental and medicinal potential, were collected from different locations in Uttarakhand region, and isolated DNA samples were amplified using fourteen ISSR primers. In the case of A. multiflora, eight of the fourteen primers tested showed amplification products with an average polymorphism of 35.39% and in the case of R. retusa, the average polymorphism was 63.32%. Cluster analysis for both species showed that samples collected from sites of similar latitudes and elevations were clustered together. Another key observation in the case of R. retusawas that the sub-clusters were formed on the basis of host tree association. This is the first report on the diversity analysis of A. multiflora and R. retusa in Uttarakhand. This study suggests that the orchids collected from locations with similar altitudes and host trees are genetically related to each other. This genetic profiling can be used as the basis to develop conservation protocols for these orchids to prevent them from entering the threatened category, as the epiphytic orchids are more susceptible to natural and anthropogenic pressures. Besides, the genetic variation analysis can be used to select the parent plants for developing commercial hybrids in both species.