贵州省烟青虫遗传多样性  

Genetic Diversity of Helicoverpa assulta(Lepidoptera: Noctuidae) in Guizhou Province

作　　者：师沛琼[1] 杨茂发[1] 吕召云[1] 李尚伟[1] 廖启荣[1] 商胜华 徐进[1] 吴怡蓓 

机构地区：[1]贵州大学昆虫研究所/贵州省山地农业病虫害重点实验室,贵阳550025 [2]贵州省烟草科学研究院,贵阳550081

出　　处：《中国农业科学》2014年第9期1836-1846,共11页Scientia Agricultura Sinica

基　　金：中国烟草总公司贵州省公司2010年度科学研究技术开发项目计划(201022)

摘　　要：【目的】探讨贵州省烟青虫(Helicoverpa assulta)不同地理种群间是否存在遗传分化及分化程度,揭示遗传分化产生的规律及机理,为指导虫情监测及制定合理的综合防治方案提供科学依据。【方法】以贵州省30个烟青虫地理种群为试验材料,从43对近缘种SSR引物中筛选出6对引物用于PCR扩增,PCR产物用8%非变性聚丙烯酰胺凝胶电泳检测,常规银染法染色。用PopGene Version1.32对各种群进行遗传多样性分析。根据Nei’s遗传距离,利用MEGA5.0软件进行UPGMA聚类分析。采用Mantel检测法比较遗传一致度与海拔差距、遗传距离与地理距离的相关性。【结果】30个烟青虫地理种群在6个微卫星位点中观测等位基因数为3—8,平均为5,有效等位基因数为1.4498—2.2219,平均为1.8594。Shannon信息指数为0.5310—1.0609,平均为0.8423。观测杂合度为0.0260—0.2672,平均为0.1239;期望杂合度为0.3123—0.5520,平均为0.4539;期望杂合度均高于观测杂合度,说明各种群以纯合子为主。烟青虫地理种群在6个微卫星位点上,FIS为0.0798—0.7906,平均为0.2801,FIT为0.4842-0.9731,平均为0.7809,FIS、FIT均为正数,说明贵州省各烟区烟青虫种群存在近交现象。FST为0.3879—0.9256,基因流Nm﹤1,说明在这6个位点上各种群间极度分化,基因交流水平低。遗传距离(D)为0.0068—2.5193,遗传一致度(I)为0.1051—0.9933,松桃与印江种群之间的遗传距离最小,遗传一致度最大,道真种群与赫章种群之间的遗传距离最大,遗传一致度最小。UPGMA聚类分析表明,贵州省30个烟青虫地理种群大致分为3部分,聚类结果在自然地理分布方面没有呈现出明显的规律性,仅部分种群体现了地理距离和遗传分化的关系。Mantel检测表明,遗传距离与地理距离无显著相关性,遗传一致度与海拔差距无显著相关性。【结论】贵州省烟青虫种群具有较丰富的遗传多样性。各种群间极度分化,遗[Objective] The objectives of the study are to explore genetic differentiation of oriental tobacco budworm （Helicoverpa assulta） among different geographic populations in Guizhou, uncover the differential law and mechanism, and to provide a scientific basis for the pest monitoring and integrated control. [Method] PCR amplifications were performed by 6 pairs of SSR primers that were screened out from 43 pairs of primers from closely-related species, using DNA from 30 H. assulta geographic populations in Guizhou as template. The PCR products were subjected to 8% non-denaturing polyacrylamide gelelectrophoresis and visualized by silver staining. Genetic diversity was analyzed by PopGene Version 1.32, and the UPGMA dendrogram was constructed by using MEGA 5.0 based on the Nei＇s genetic distance. The correlation between genetic and geographic distances as well as between genetic identity and elevation were analyzed by using Mantel. [Result] The observed and effective number of alleles ranged from 3 to 8 with an average of 5 and from 1.4498 to 2.2219 with an average of 1.8594, respectively. Shannon＇s information index ranged from 0.5310 to 1.0609 with an average of 0.8423. The observed （14o） and expected heterozygosity （He） varied from 0.0260 to 0.2672 with a mean of 0.1239 and from 0.3123 to 0.5520 with a mean of 0.4539, respectively. The He was higher than the Ho, suggesting that all populations were mainly in homozygous condition. Fis changed from 0.0798 to 0.7906 with a mean of 0.2801; Frr changed from 0.4842 to 0.9731 with a mean of 0.7809. Both Fts and Flrwere positive, indicating that there existed inbreeding in the all populations ofH. assulta from tobacco-growing areas of Guizhou. Fsr ranged from 0.3897 to 0.9256 and gene flow （Nm） was less than 1, which reflected high genetic differentiation and a low level of Nm among all the populations. Genetic distance was in a range of 0.0068-2.5193 and genetic identity was in a range of 0.1051-0.9933. The minimum genetic distance （0.0068） and the

关 键 词：贵州 烟青虫 微卫星标记 遗传多样性 遗传分化 

分 类 号：S433.4[农业科学—农业昆虫与害虫防治]