Population Genetic Structure of Three Major River Populations of Rohu, Labeo rohita (Cyprinidae: Cypriniformes) Using Microsatellite DNA Markers

Determining the genetic structure is essential for developing conservation and stock improvement plans. Four dinucleotide microsatellite loci were analysed to reveal population genetic structure of the Indian major carp, Labeo rohita collected from three major rivers namely the Halda, the Jamuna, and the Padma in Bangladesh. The four loci were polymorphic (P-95) in all the populations. The populations varied in the number and frequencies of alleles as well as heterozygosities in the loci analyzed. Population differentiation (F-ST) value between the Halda and the Jamuna population was significant (P < 0.05). Relatively high level of gene flow and low level of F-ST values were found between the Padma and the Jamuna population. The unweighted pair group method with averages (UPGMA) dendrogram based on genetic distance resulted in two clusters: the Halda population was alone in one cluster whereas the Jamuna and the Padma made another cluster. The results revealed a relatively low level of genetic variability in the river populations of L rohita in Bangladesh.