几种肿腿蜂mtDNA COⅡ-COⅢ区域序列及分子系统进化分析

Sequence Analysis on Genes Region from COⅡ to COⅢ in mtDNA of Several Sclerodermus Species in China for Biological Control

部分硬皮肿腿蜂属Sclerodermus的寄生蜂用于我国蛀干害虫的生物防治,取得很好的效果,但这些肿腿蜂近缘种的外部形态特征十分相似,本研究的目的是利用分子手段鉴定肿腿蜂近缘种。对近年来我国用来防治蛀干害虫的肿腿蜂近缘种mtDNA COⅡ-COⅢ基因区域进行了序列测定与分析。结果显示所测定的1700 bp的片段中,含有COⅡ基因部分序列,完整的tRNA-Asp基因、tRNA-Lys基因、ATPase6基因和ATPase8基因以及部分COⅢ基因。对基因序列整体分析结果表明,管氏肿腿蜂与川硬皮肿腿蜂的序列相似性最高,为100%,白蜡吉丁肿腿蜂与松脊吉丁肿腿蜂Sclerodermus sp.(No.2)的序列相似性最低为96.88%。1700 bp的序列中包含68个变异位点,平均遗传距离为0.011。分子系统树分析结果表明,白蜡吉丁肿腿蜂与其他5个种(管氏肿腿蜂、川硬皮肿腿蜂、落叶松吉丁肿腿蜂、松脊吉丁肿腿蜂、苹小吉丁肿腿蜂)亲缘关系最远,形成一个单系群。另外一个大群又分为4个亚群,而Sclerodermus sp.(No.1)的所有个体在该大群内与其他种亲缘关系最远,单独形成一个亚群。本研究首次获得我国常用于生物防治的6种肿腿蜂的mtDNA COⅡ-COⅢ序列,对比不同基因序列分析,mtDNA ATPase6基因最适合区分6种不同肿腿蜂,可以作为肿腿蜂近缘种分类鉴定的有效基因。

Several species of genus Sclerodermus are currently the most important natural insect enemies against forest wood borer pests, mainly buprestid and cerambycid beetles. We aimed to use molecular methods to identify Sclerodermus species that are difficult to distinguish morphologically. Further, we provided a reliable evidence for traditional morphological identification. Sequence analysis was on genes region from COⅡ to COⅢ in mtDNA of several Sclerodermus species used in biological control in recent years. The sequence contained partial mtDNA COⅡ, t RNA-Asp, t RNA-Lys, ATPase6, ATPase8 and part COⅢ, measuring about 1700 bp. Sequence similarity between S. guani and S. sichuanensis was 100%, while it was 96.88% between S. pupariae and Sclerodermus sp.（No. 2）. The 1700 bp region of mtDNA COⅡ-COⅢ was obtained for the 106 individuals, including 68 variable sites and sequence divergences（K2P） of 0.011. NJ analysis of the mtDNA COⅡ-COⅢ sequences revealed that the S. pupariae were merged into one haplogroup, and Sclerodermus sp.（No. 1） were merged into another haplogroup. The sequences of Sclerodermus mtDNA COⅡ-COⅢ were first reported in this paper. The comparative analysis results of different mtDNA sequences show that the ATPase6 gene is the most suitable for distinguishing the sibling species of Sclerodermus.