内蒙古赛罕乌拉自然保护区东北马鹿种群遗传多样性与性别结构分析

Genetic diversity and sex structure of red deer population in Saihanwula Nature Reserve,Inner Mongolia

东北马鹿(Cervus canadensis)种群面临着地理隔绝和生境破碎化等问题,对其种群遗传多样性和性别结构的研究,有助于了解其隔离种群的生存现状,为保护与管理工作提供科学依据。本研究利用8对微卫星分子标记,对内蒙古赛罕乌拉国家级自然保护区的456份马鹿粪便样品进行遗传多样性分析。结果识别出2015年冬季56只个体,2016年秋季41只个体;微卫星位点平均期望杂合度为0.650 1,平均多态信息含量为0.603 5,表明该地区马鹿种群的遗传多样性处于中等偏上水平。种群遗传分化系数为-0.053 99、近交系数为0.086 67、基因流为2.942 11,说明该马鹿种群基因交流普遍,近交水平低。基于SRY基因的方法进行性别鉴定,种群雌雄性比在冬季为1.8∶1,秋季为0.71∶1。本研究显示,该区域马鹿种群目前遗传多样性较为丰富,但现有种群集中分布于保护区内,处于相对隔离状态,长期发展则存在种群内部近交的风险。因此,加强对种群遗传结构和生存状态的监测,并促进与附近区域马鹿个体的交流,将有助于保持区域性东北马鹿种群长期繁盛。

Red deer(Cervus canadensis) in northeast China are geographically isolated and their habitat is fragmented;therefore,studies on genetic diversity and sex structure are useful for understanding survival trends of isolated populations and improving conservation efforts for red deer in this region.In this study,we used eight pairs of microsatellite molecular markers to analyze the genetic diversity and sex structure of a population of red deer from Saihanwula National Nature Reserve in Inner Mongolia using 456 fecal samples collected in the field.The analysis identified 56 individuals in the winter of 2015 and 41 individuals in the autumn of 2016.The average expected heterozygosity of the eight microsatellite loci was 0.650 1 and the average polymorphic information content was 0.603 5,indicating that the genetic diversity of the red deer population was high.The genetic differentiation coefficient was-0.053 99,the inbreeding coefficient was 0.086 67 and the gene flow was 2.942 11,indicating that the red deer population had normal gene exchange and a low level of inbreeding.Based on the sex-determining region Y(SRY gene),the sex ratio of females to males was 1.8∶1 for the winter population and 0.71∶1 for the autumn population.This study reveals that although this isolated red deer population currently has relatively high genetic diversity,there is a risk of inbreeding in the long term.Therefore,strengthening population monitoring,improving genetic structure and promoting exchanges of individuals with nearby populations will help to ensure the long-term survival of this and other red deer populations in Northeast China.