Population genetics of Indian white shrimp, Penaeus indicus (H. Milne Edwards, 1837) from Indian waters

Abstract

The Indian white shrimp, Penaeus indicus (H. Milne Edwards, 1837), is a commercially important marine crustacean species, widely distributed along the Indo-Pacific region. The population genetic structure and genetic diversity of P. indicus were studied using the mitochondrial 16S rRNA gene. A total of 121 individuals representing seven populations from distant parts of India were used for the study. Results indicated that there were seventeen haplotypes and the mean haplotype diversity (Hd) was relatively moderate when there was a low level of nucleotide diversity (π). AMOVA analysis indicated that variation within populations contributed to 69.32% of the total variation. All the populations, except Kanyakumari, showed high polymorphism and haplotype diversity, indicating genetically varied stocks in the wild. The pair-wise FST value ranged from as low as -0.03587 between Kanyakumari and Kakinada to as high as 0.68650 between Kakdwip and Kakinada populations with an overall FST value of 0.30684 (p<0.05). The pattern of the haplotype network and phylogenetic tree revealed two major groups. The Tajima’s D statistic showed the presence of a recent expansion of the population. Our study exhibits a polyphyletic relationship in P. indicus between Kakdwip (West Bengal) and other populations and the high haplotype diversity and genetic divergence of Indian white shrimp can be utilized for selective breeding programs.