Abstract
The genetic structure of red sea bream population Pagrus major, was assessed from fish collected at eight locations along Japan, China and the Southwest Pacific. Genetic diversity and population subdivision was estimated based on microsatellite DNA analysis. The results obtained with three microsatellite loci showed a high genetic diversity for Japan and China locations with mean number of alleles per locus between 21 to 30, and mean observed heterozygosities ranging from 0.804 to 0.867. Southwestern Pacific samples showed intermediate genetic diversity, with mean values of 14 alleles per locus and an observed heterozygosity of 0.7. Significant pairwise FST and RST values were observed between locations showing that the red sea bream population is structured both in the North and Southwest Pacific. According to a hierarchical Analysis of Molecular Variance (AMOVA) performed among groups of locations, three populations are proposed: Australia, New Zealand and Japan-China. Moreover, a division into three subpopulations is proposed for the Japan and China region. One located in the South China Sea, one more in the area covered by the East China Sea, Southwest Japan and Japan Sea, and the last one along the Pacific coast of Japan. The importance of considering these findings for design of management strategies of both the commercial fishery and stock enhancement programs is addressed.
