利用ITS2序列识别盾蚧科昆虫

Identifying the armored scales (Hemiptera:Diaspididae) using ITS2 gene

[目的]盾蚧科隶属于半翅目蚧总科,大多数种类是危害很严重的经济害虫。由于其外部形态特征简单,导致识别该类群物种相对困难。利用DNA条形码为解决这个问题提供有效的方法。[方法]共采集了5个省47个样本,属于7属11个种,并从GeneBank下载了4属5个物种的序列。采用distance-based方法和tree-based方法对ITS2基因片段是否可以作为盾蚧科DNA条形码的补充做了分析。[结果]虽然ITS2没有Barcode gap存在,然而所有的分支都表现出了明显的单系群,表现出较高的物种识别能力。同时,Best Match(BM)和Best closed match(BCM)也表现出了超过90%的识别能力。[结论]这些结果证实ITS2在盾蚧科物种的识别有效性方面具有较高的应用价值。

[Objective]Armored scale is one of the family of coccoidea that most species are considered to be serious economic pests.However,identification of Diaspididae species is difficult due to the shortage of easily distinguishable morphological characters.As a useful tool for molecular species identification,DNA barcoding might offer potential using for armored scale identification and taxonomy.[Methods]74sequences belongs 16 species with distance-based method and tree-based method were employed to assess the effectiveness of ITS2 gene fragment.[Results]The result showed there was no barcode gap between intraspecies and interspecies distance.However,all phylogenetic trees exhibited similar topology and could distinguish all surveyed species in Diaspididae with high support values.BM and BCM all showed more than 90%identification success rate.[Conclusion]The study confirm ITS2 gene is effective for the identification of armored scale.