MICROSATELLITE MARKERS BASED GENETIC STRUCTURE OF ROHU (Labeo rohita) IN SELECTED RIVERINE POPULATIONS OF PUNJAB, PAKISTAN

Genetic integrity of distinct local fish populations is being compromised in face of growing anthropogenic interventions and environmental degradation. The present study examined the genetic structure of Rohu, Labeo rohita in riverine populations of Punjab, Pakistan, as influenced by anthropogenic interventions. Average 25 fish specimens were collected from each target site. Fifteen microsatellite markers with varying levels of polymorphism were employed for PCR amplification of target loci. The results revealed moderate level of genetic diversity in riverine populations. A total of 70 alleles with an average of 4.6 alleles per locus were detected on fifteen heterologous microsatellite loci. Observed heterozygosity varied from 0.5786 up to a maximum of 0.6293. The average value of FIS ranged from 0.086 to 0.1835. About 33% of the total locus-pair combinations showed significant deviations from HWE (P<0.05, P<0.01, P<0.001) with apparent heterozygote deficits. The results of AMOVA showed that 90.40% genetic variation existed at the intra-population level while 9.12% at inter-populations level. The UPGMA dendrogram revealed that the populations clustered onto two major branches by showing their genetic relatedness partially following their geographic distribution. The dwindling populations of the species in natural resources of Pakistan demand critical efforts to conserve the genetic diversity.