僵蚜中寄生蜂的分子鉴定——以桃粉大尾蚜为例

Molecular identification of parasitoids in aphid mummies:a case study of Hyalopterus arundiniformis

蚜虫是重要的农林业害虫,寄生蜂在蚜虫的生物防治中扮演着重要角色。调查寄生性天敌资源,理解寄生性天敌与蚜虫的关系,是发展绿色防控技术的重要基础。寄生蜂由于个体小且形态相似,传统的形态鉴定较为困难。DNA条形码可以快速高效地帮助形态分类鉴定上存在困难的物种,它作为一种简便、快捷的分子技术,在物种鉴定中广泛使用。本研究以桃粉大尾蚜(Hyalopterus arundiniformis)为例,利用DNA条形码技术探究蚜虫寄生性天敌多样性。共采集到22号样品,其中包括14号僵蚜样品和8号从僵蚜体内羽化的寄生蜂样品。基于DNA条形码技术共鉴定出5种桃粉大尾蚜僵蚜体内的寄生蜂,包括初寄生蜂黍蚜茧蜂(Ephedrus nacheri)、麦蚜茧蜂(Ephedrus plagiator)、粗脊蚜茧蜂(Aphidius colemani)、棉蚜蚜小蜂(Aphelinus varipes)和重寄生蜂蚜虫宽缘金小蜂(Pachyneuron aphidis),其中棉蚜蚜小蜂是首次在桃粉大尾蚜中发现。使用DNA条形码鉴定饲养出来的寄生蜂共发现5个物种,利用多种引物鉴定僵蚜内寄生蜂时发现了除黍蚜茧蜂外的其他4个物种。说明通过对僵蚜的DNA条形码鉴定基本能够揭示桃粉大尾蚜的寄生性天敌多样性,对其他拟寄生物的物种鉴定具有重要的参考意义。不同引物对僵蚜鉴定效果与寄生蜂相似。4对引物对僵蚜的鉴定效果不同,其中通用引物Lco1490/Hco2198对僵蚜体内寄生蜂有较好鉴定效果。建议研究僵蚜体内寄生蜂多样性时,需要多对引物同时使用。

Aphids are important pests in agriculture and forestry,which can be effectively controlled by parasitoids.Understanding the aphid-parasitoid relationships can provide basic knowledge to develop significant bio-control techniques.Parasitoids are difficult to identify due to their small body and similar morphology.This problem can be solved by DNA barcoding,which is a simple and widely used method for species identification.This study used DNA barcoding to investigate parasitoid diversity of aphid pests by taking Hyalopterus arundiniformis as an example.We collected 22 samples including 14 mummified aphids and 8 parasitic wasps.Five different parasitoids were identified with DNA barcoding in mummified aphids,including 4 primary parasitoids:Ephedrus nacheri,Ephedrus plagiator,Aphidius colemani,Aphelinus varipes,and 1 hyperparasitoid:Pachyneuron aphidis.Moreover,A.varipes was firstly found in H.arundiniformis.DNA barcoding also identified five species of parasitic wasps reared from mummified aphids.Besides E.nacheri,the other four species could be directly identified based on mummified aphids.This indicates the identification of parasitic wasps in mummified aphids through DNA barcoding can basically reveal the diversity of parasitic natural enemies of H.arundiniformis,which also has important reference value for the identification of parasitoid for other aphid pests.Different primers had the same or slightly lower effect on identification success based on mummified aphids than parasitic wasps.Among the four pairs of primers,the universal primers Lco1490/Hco2198 had better identification efficiency for parasitoid wasps in mummified aphids.Therefore,when studying the diversity of parasitoid wasps in aphids,it is necessary to use multiple pairs of primers simultaneously.