Genetic Diversity Analysis of Indian Salmon, Eleutheronema tetradactylum from South Asian Countries Based on Mitochondrial COI Gene Sequences

Abstract

Eleutheronema tetradactylum is an important commercial fish species exposed to intense exploitation both in Southeast Asian countries and Northern parts of Australia. Research on the population structure of E. tetradactylum in these coastal waters is substantial in order to ensure sustainable use and appropriate resource management. In this study, genetic variation, diversity and population structure of E. tetradactylum among four FAO fishing areas, along South Asian countries, were evaluated using cytochrome c oxidase subunit I (COI) gene. Totally 30 sequences of COI gene were collected from four FAO fishing areas. Among these 30 individuals, 18 distinct haplotypes were defined. High levels of haplotype diversity (hd = 0.952 ± 0.096) and nucleotide diversity (Ï€ = 0.01536 ± 0.00312) were observed in the population within the Bay of Bengal. No haplotype and nucleotide diversity were observed in South China Sea population. Hierarchical analysis of molecular variance (AMOVA) indicated that 0.81% of the genetic variation occurred within the populations, while 7.09% variation occurred among populations. Significant genealogical branches were recognized in North Australian populations (one clade), South China Sea populations (one clade), Arabian Sea and Bay of Bengal populations (one clade) on the neighbor-joining tree. These results suggested that E. tetradactylum populations in FAO fishing areas 51, 57 and 61 have developed different genetic structures. Tests of neutral evolution and mismatch distribution suggest that a population growth of E. tetradactylum may take place in these fishing areas.