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蚜小蜂Bemisia tabaci是烟粉虱的重要天敌,其中双斑恩蚜小蜂Encarsia bimaculata,丽蚜小蜂E.formosa以及浅黄恩蚜小蜂E.sophia是国内烟粉虱寄生蜂3个优势种。本研究以采自中国华南、华东、华北、西南地区以及马来西亚、埃及的E.bimaculata、E.formosa和E.sophia3个优势种的8个不同地理种群为研究对象,对其28S rRNA D2和D3扩展区序列进行了测定和分析。结果表明:Encarsia属的恩蚜小蜂其28S rRNA D2和D3序列在种间水平上高度保守;与丽蚜小蜂相比,双斑蚜小蜂与浅黄恩蚜小蜂在遗传关系上更为接近。依据28S rRNA和D2序列的系统发育分析结果显示,同一种的蚜小蜂其种内也存在一定的遗传分化,比如中国广东的浅黄恩蚜小蜂种群与澳大利亚、西班牙、埃及和埃塞俄比亚的浅黄恩蚜小蜂种群接近,而与泰国的种群的亲缘关系则较远。在系统发育树上,来自不同国家的(苏丹、埃及和危地马拉以及澳大利亚)的双斑蚜小蜂种群聚集在同一分支上;同时,来自中国衡水和昆明的丽蚜小蜂种群也与来自美国的丽蚜小蜂种群聚集在一起,却与埃及的种群相距较远。对造成这种同种寄生蜂不同种群之间在遗传距离和地理距离不对称的原因进行了探讨。
Bemisia tabaci is an important natural enemy of Bemisia tabaci. Among them, Encarsia bimaculata, E.formosa and E.sophia were the dominant parasitoids of B. tabaci . In this study, eight different geographical populations of three dominant species, E. bimaculata, E. formosa and E. sophia, collected from South China, East China, North China, Southwest China, and Egypt of China were studied. Their 28S rRNA D2 and D3 The extended region sequences were determined and analyzed. The results showed that: Encarsia genus Aphididae was 28S rRNA D2 and D3 sequences highly conserved at the interspecies level; Compared with the Aphis gossypii, the two-spotted aphid Bumblebee and the yellow-winged aphid Bumblebee more genetic relationship Close to According to the phylogenetic analysis of 28S rRNA and D2 sequences, there was also some genetic differentiation within the same species of Aphis gossypii, such as the buffalos population of A. gigas in Guangdong province, China, the pale yellow benevolence population of Australia, Spain, Egypt and Ethiopia Aphid islets close to the population, but the genetic relationship with the Thai population is far. In the phylogenetic tree, the two-spotted aphid wasp populations from different countries (Sudan, Egypt and Guatemala and Australia) are clustered on the same branch. At the same time, the populations of A. aphylla from Hengshui and Kunming in China are also similar to those from the United States The aphid collects together in small groups, but far away from the Egyptian population. The reasons for the asymmetric genetic distance and geographic distance between different populations of this kind of parasitoids were discussed.