Single Genetic Stock Revealed by Microsatellite Markers Among Wild Populations of Cirrhinus mrigala from Peninsular India

Cirrhinus mrigala (mrigal) is one of the Indian major carps widely cultured in the whole Indian subcontinent. Population genetic structure of this species from Peninsular Rivers of India is lacking. Among DNA markers, microsatellites are excellent tools to evaluate genetic variation of populations. In this study, genetic variation of six peninsular riverine mrigal populations was evaluated using seventeen microsatellite loci. In analyzing 288 samples, the number of alleles ranged from 4 to 27; observed heterozygosity from 0.595 to 1.00, expected heterozygosity from 0.586 to 0.959 and inbreeding coefficient (FIS) ranged from -0.034 to 0.02. Exact test for Hardy Weinberg disequilibrium revealed that one locus was not in equilibrium across the rivers except one. The AMOVA analysis revealed the main source of genetic variation to be within the population (94.54%) than among the populations (5.46%). The Nei's genetic distance and structure analysis depict river Narmada and Mahi populations are different from the four east coast rivers. The overall Fst (0.05462) data showed moderate differentiation among the six populations. The results of this study provide essential information to resource recovery and help in delineating populations for fishery management. Besides, the data will provide a valuable baseline for further investigations on the geographic distribution of this commercially important fish species.

Automated summary

This study assessed the genetic variation of six peninsular riverine mrigal populations using seventeen microsatellite loci, revealing that the main source of genetic variation is within populations rather than among populations. The Nei's genetic distance and structure analysis showed differences between the Narmada and Mahi river populations and the four east coast rivers. The overall Fst data indicated moderate differentiation among the six populations.