Genetic Relationship and Structural Analysis of Resident Pacific Salmon Oncorhynchus Masou in Mijiang River, China

Abstract

Masu salmon Oncorhynchus masou has been listed as national second-class protected species in China, and many of its local populations have been under threats of decline because of environmental deterioration by human activity, such as habitat loss, water pollution, or dams. Genetic characteristics should be clarified in wild masu salmon population for an effective protection and recovery. In the present study, we explained genetic relationship and structure of masu salmon population in Mijaing River by sequencing the COI gene and analyzing microsatellite makers. Results of COI sequences analysis revealed 15 gene variable sites in approximately 696 bp, which defined 12 haplotypes, including some haplotypes related to geographic regions. The NJ tree indicated genetic relationship that we preliminarily inferred, that is, the masu salmon from Mijiang River belonged to the cherry salmon family (O. masoumasou). Results based on 14 microsatellite loci showed high haplotype diversity and low nucleotide diversity, indicating low genetic diversity of wild masu population in Mijaing River. The observed genetic structure was influenced primarily by bottlenecks due to overfishing and habitat loss. Since masu salmon has become highly vulnerable in China, we recommend to strengthen the protection of resident masu salmon population.

Genetic Diversity and Structure of Chinese Chum Salmon (Oncorhynchus keta) Between Wild and Hatchery Populations Based on SSR Markers

“…Tumen River is the boundary river between China and North Korea, because of over-exploitation and no protection in North Korea during the closure period, chum salmon has become the highly vulnerable population in China (Han et al, 2019;Li et al, 2017). At present, stock enhancement was mainly used to achieve the population expansion (Kitada, 2014;Kaeriyama et al, 2012), the shery department of Jilin Province has carried out the activities of the stock enhancement of chum salmon for more than 10 years, 400,000 to 500,000 juveniles were released into Hunchun River and Mijiang River, the tributaries of the Tumen River every year (Liang et al 2021). After several years of continuous investigation, the number of the chum salmon population has recovered in the Tumen River.…”