Population structure and gene migration in pink salmon (Oncorhynchus gorbuscha) from the Sakhalin-Kuril region.

摘要

Data on allozyme variation (MDH-B1,2*, G3PDH-1*, PGM-2*, PGDH* and MEP-2* loci) in adult pink salmon (spawners) and pre-emergent and migrating fry from the Sakhalin-Kuril region, which were obtained between 1979 and 1989, were analysed. The averageinterpopulation genetic diversity per generation (GST) in spawners was 0.29%, including 0.11% gene differentiation between local populations (southwestern and southeastern regions of Sakhalin, the Iturup Island) and 0.18% gene differentiation between river populations within a locality. Multidimensional scaling showed the specific geographical distribution of spawner clusters and the maintenance of genetic differentiation in both spawners and fry. Genetic differentiation was characteristic of populations from rivers separated by only a few dozens of kilometres. Interpopulation genetic distances in fry were significantly higher than in spawners, suggesting the effect of local selection and gene migration on the population structure. Based on this difference, the average intensity of migration gene exchange between populations from the Sakhalin-Kuril region was estimated as 7.2%.