Genetic Structure of the Oriental River Prawn ( Macrobrachium nipponense  ) from the Yangtze and Lancang Rivers Inferred from COI Gene Sequence

This study analyzed nucleotide sequences from the mitochondrial cytochrome oxidase submit (COI) gene region (450 bp) to investigate the genetic structure of the oriental river prawn (Macrobrachium nipponense) among nine populations from the Yangtze and Lancang Rivers. A total of 79 individuals were collected for this work. Eighty-nine nucleotides were found to be variable, resulting in 46 haplotypes. Among the nine populations,the population from Kunming shows the greatest level of variability (h=1.000,π=0.028), whereas the population from Chongqing exhibits the lowest level of variability (h=0.700,π=0.008). Analysis of molecular variance suggested that of the total genetic diversity,9.66% was attributable to inter-population diversity and the remainder (90.34%) to differences within populations. A molecular phylogenetic tree constructed using the Neighbor-joining (NJ) method showed that the 46 haplotypes were assigned to two clades associated with geographic regions. These results provide basic information for the conservation and sustainable exploitation of this species.

Keywords
Macrobrachium nipponense, COI gene, Genetic structure, Genetic variation, Haplotype