DNA条形码技术在小花蝽属昆虫分类鉴定中的应用

Application of DNA Barcoding Technique for Species Identification of Orius Wolff(Heteroptera: Anthocoridae)

本研究利用DNA条形码技术对13种小花蝽属Orius Wolff昆虫进行了鉴定,进行了59条COI基因序列碱基组成及种内、种间遗传距离的分析,采用邻接法、最大简约法、贝叶斯推论法构建了系统发育树。结果表明,小花蝽属昆虫COI基因序列碱基组成与典型的昆虫线粒体DNA一致,A+T平均含量(66.4%)明显高于G+C含量,密码子的第3位A+T含量高达90.7%,碱基替换多为同义替换;13种小花蝽种内平均遗传距离为0.008,种间平均遗传距离为0.128,种内、种间遗传距离没有重叠区域。3种方法构建的系统发育树的聚类分析与形态学鉴定结果基本一致,除微小花蝽Orius minutus(Linnaeus)可能存在隐存种现象外,其他同一种群的不同个体单独聚为一支。利用DNA条形码技术对小花蝽属昆虫进行物种快速分子鉴定具有可行性。

Thirteen Orius species were differentiated using a DNA barcoding technique. Base composition of 59 COI gene fragments were analyzed, intra-and inter-species genetic distances were calculated and phylogenetic trees were established based on neighbor-joining method, maximum parsimony method and bayesian method, respectively. Results showed that base composition of 13 Orius species＇ COI gene sequence was consistent with the typical insect mitochondrial DNA, A＋T average content（66.4 %） was higher than G＋C average content, A＋T content was 90.7% in 3rd position of codon, most base substitutions were synonymous substitutions. Average intra-specific genetic distance was 0.008, average inter-specific genetic distance was 0.128, the two were not overlapped. The results of cluster analysis, based on three different methods, were basically consistent with the results of morphological identification, different individuals of the same population were gathered to a branch in the dendrograms, but there may be a cryptic species of Orius minutus（Linnaeus）. The DNA barcoding technique can be potentially used for quick identification of Orius species.