我国细鳞鲑的亚种分化与遗传多样性分析

Brachymystax lenok belonging to Brachymystax, the family Salmonidae and order Salmoniformes, is an important cold water economic fish. Due to the wild stocks of Brachymystax lenok decline dramatically in several decades, the Qingling lenok has been listed as II class state protected wild animal in 1998. There is an controversy of subspecies differentiation on Brachymystax lenok in the fish taxonomy field of China, a view that the Brachymystax lenok in Qinling region (Qingling lenok) as a new subspecies, is different from that distributed in Xinjiang and Heilongjiang Province, other is that no subspecies differentiation of Brachymystax lenok in China. In this study, the Brachymystax lenok in Qinling region group (Shaanxi and Gansu Province) and the other region group (Xinjiang and Heilongjiang Province) was selected as experimental materials, based on comparative morphological characteristics (shape measurement and statistical analysis of the combination), and molecular genetic differences (sequence differences of mitochondrial D-Loop control region and variability of microsatellite loci analysis) to determine the subspecies differentiation of Brachymystax lenok in China, Also, the genetic diversity of Brachymystax lenok from these above geographic populations was analyzed. Implementation of this study, we try to clarify subspecies differentiation of controversy to Brachymystax lenok in China, accumulate data for fish classification, and provide the scientific basis for the protection and utilization of the endangered species Qinling lenok.

细鳞鲑 Brachymystax lenok 隶属于鲑形目、鲑科、细鳞鱼属，是我国重要的 冷水性经济鱼类，但近年来其野生种群数量锐减，其中秦岭细鳞鲑在 1998 年被列为国家 II 级保护动物。然而，目前鱼类学界对我国细鳞鲑的亚种分化问题仍有争议，一种观点认为秦 岭地区细鳞鲑为一个新亚种；另一种则认为细鳞鲑在我国不存在亚种分化。本研究选取我国 细鳞鲑秦岭地区群体（陕西、甘肃）和指名亚种群体（新疆和黑龙江）为实验材料，基于比 较形态特征（形态度量学和统计分析相结合）和分子遗传差异(线粒体 D-Loop 控制区序列差异和微卫星位点的变异)，判别秦岭细鳞鲑与指名亚种的分化是否到亚种水平；同时分析细鳞鲑不同地理种群的遗传多样性。本项目的实施，试图澄清我国细鳞鲑的亚种分化问题的争议，为鱼类分类学基础研究积累资料，为濒危物种秦岭细鳞鲑的保护和利用提供科学依据。