Morphometric and Genetic Variation in Three Populations of Indian Salmon (Polydactylus plebeius)

Morphometric character analyses and RAPD was used to discriminate and ratify the status of three populations of Indian salmon, Polydactylus plebeius along the coromandel coast of India. Morphometric analyses showed a clear pattern of differentiation between the stocks and revealed the discreteness of two groups, southern stock (Pazhayar) and northern stock (Cuddalore). The univariate analysis of variance showed significant differences between means of the samples for most morphometric descriptors. A total of 1077 scorable bands were produced using all ten arbitrary primers in three populations. An un-weighted pair-group method with arithmetic mean (UPGMA) dendrogram was constructed based on genetic values to show the genetic relationship among the three populations. The genetic diversity (H) of P. plebeius in Cuddalore was more (0.0733 ± 0.0648) than Pazhayar (0.0609 ± 0.0416) and Vellar (0.0613 ± 0.0344) populations. All the three populations had significantly (p<0.001) higher interpopulation genetic distance value than the intrapopulation value. Further molecular studies, comprising more markers and populations are still required to precisely evaluate the genetic structure of threadfin fishes throughout the Indian coast.