中文摘要：

【目的】沙葱萤叶甲Galeruca daurica（Joannis）是一种近年来在内蒙古草原上猖獗成灾的新害虫,本研究旨在明确内蒙古沙葱萤叶甲不同地理种群间的遗传分化和基因交流程度。【方法】应用5对微卫星引物分析了沙葱萤叶甲8个地理种群的遗传多样性、基因流和遗传分化。【结果】5个位点等位基因数为10~18,有效等位基因数为9.2796~16.0388,多态信息含量值为0.6760~0.8985,期望杂合度为0.3430~0.5284,说明所选5个微卫星位点均为高度多态性位点。8个种群的期望杂合度为0.2216~0.3701,平均值为0.2680;种群间遗传分化系数为0.1244~0.4116,平均值为0.2521;种群间基因流为0.3574~1.7596,平均值为0.9622。8个地理种群根据遗传距离聚为3个分支,遗传距离与地理距离呈显著的正相关关系（r=0.4854,P=0.0180）。【结论】沙葱萤叶甲种群遗传多样性低,不同地理种群之间基因流较小,遗传分化程度高;沙葱萤叶甲迁移能力弱和地理阻碍可能是限制其基因交流和导致遗传高度分化的主要原因。

英文摘要：

【Aim】Galeruca daurica（ Joannis） is a new pest causing damages seriously in Inner Mongolia grasslands in recent years. This study aims to investigate the genetic differentiation and gene flow among different geographic populations of G. daurica in Inner Mongolia. 【Methods】By using five microsatellite primer pairs,we analyzed the genetic diversity,gene flow and genetic differentiation among eight populations of G. daurica. 【Results】The number of alleles and effective number of alleles per locus ranged from 10 to 18 and 9. 2796 to 16. 0388,respectively. The polymorphic information content per locus ranged from 0. 6760 to 0. 8985 and the expected heterozygosity ranged from 0. 3430 to 0. 5284,demonstrating the high degree of polymorphism. Moreover,the expected heterozygosity of the eight populations ranged from 0. 2216 to 0. 3701,with the average of 0. 2680. The genetic differentiation index（ FST） ranged from 0. 1244 to 0. 4116,with the average of 0. 2521,and the gene flow（ Nm） ranged from0. 3574 to 1. 7596,with the average of 0. 9622. Eight populations were clustered into three groups according to their genetic distances,and the genetic distance between populations showed a highly significant correlation with the geographical distance（ r = 0. 4854,P = 0. 0180）. 【Conclusion】The G.daurica populations are characterized by low genetic diversity. The gene exchange seldom exits and high genetic differentiation occurs between different geographic populations. The lower migration ability of this leaf beetle and geographic obstacles might be the main reason for the low gene flow and high genetic differentiation.