Genetic structure of masu salmon (Oncorhynchus masou) populations in Hokkaido, northernmost Japan, inferred from mitochondrial DNA variation |
| |
Authors: | S. Kitanishi,&dagger ,K. Edo,&Dagger ,T. Yamamoto,§ ,N. Azuma, ,O. Hasegawa, S. Higashi |
| |
Affiliation: | Graduate school of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan; , Agency for Cultural Affairs, Tokyo 100-8959, Japan; , Nippon Veterinary and Animal Science University, Tokyo 180-8602, Japan; and Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-0821, Japan |
| |
Abstract: | Genetic structure of masu salmon Oncorhynchus masou populations in Hokkaido was examined by analysing mtDNA NADH dehydrogenase subunit 5 gene (561 bp) of 382 individuals collected from 12 rivers, in which there were no records of artificial release. Analysis of molecular variance showed that between groups level and between populations within-group level explained each c. 10% of genetic variance. In neighbour-joining tree, four populations located in southern Hokkaido were clustered into a single group; however, other populations did not form any clear clusters. Fu's F S, Tajima's D and a mismatch distribution test indicated a sudden expansion of population in the entire population of Hokkaido and the northernmost population of Chiraibetsu, which was genetically close to the southern Hokkaido group. The Sea of Japan and southern rivers, including those of southern Hokkaido, seem to have served as refugia for masu salmon during glacial periods, and their dispersal and straying in interglacial periods affected the genetic structure of masu salmon populations in Hokkaido. |
| |
Keywords: | genetic structure Hokkaido masu salmon ND5 Oncorhynchus masou straying |
|
|