Molecular genetic diversity of a cultivable freshwater prawn Macrobrachium dayanum (Henderson, 1893) from Outer Himalayas, India

Abstract

In the present investigation, genetic polymorphism and variability in seven natural populations of Himalayan prawn Macrobrachium dayanum were assessed by polymerase chain reaction (PCR) based two molecular techniques viz., ISSR and RAPD. Genomic DNA of each sample was isolated by Phenol–chloroform method. Genotyping by selective ISSR and RAPD markers revealed high level of genetic variability among seven populations depicted by 86.9% and 96.2% polymorphism respectively. The combined results of two molecular marker assays disclosed that populations of Nagri and Chadwal streams were genetically closest having highest values of Jaccard similarity (0.419) and Nei & Li coefficient (0.591) whereas the populations of Chadwal and Sai streams were genetically least related with lowest values of Jaccard similarity (0.206) and Nei & Li coefficient (0.342). Cluster analysis by UPGMA dendrograms revealed that seven populations of M. dayanum were distributed into two major groups which were further divided into sub-groups. The principal coordinate analysis was consistent with the UPGMA Clustering of the populations. Overall, the population of Kheri stream was found to be quite distinct from rest of six populations. The findings of present communication will serve for the sustainable conservation program of the Himalayan prawn and selection of its desired populations having higher genetic variability to withstand adverse conditions for future venture of commercial prawn culturing in the rural areas of Himalayas. In addition, the results of current study set a stage to evaluate the reasons for lesser genetic diversity of the studied species in some of the streams of Jammu and the way forward to improve the status of these lotic ecosystems to enhance the genetic polymorphism in M. dayanum.