稻纵卷叶螟绒茧蜂对寄主的搜索行为  

Host searching behaviour of Apanteles cypris Nixon(Hymenoptera:Braconidae)

作　　者：周慧[1] 张扬[2] 吴伟坚[1] 

机构地区：[1]华南农业大学昆虫生态研究室,广州510642 [2]广东省农业科学院植物保护研究所,广州510640

出　　处：《生态学报》2012年第7期2223-2229,共7页Acta Ecologica Sinica

基　　金：国家重点基础研究发展计划(973计划)(2006CB100206);广东省科技厅国际合作项目(2009B050300001)

摘　　要：稻纵卷叶螟绒茧蜂是稻纵卷叶螟幼虫的重要天敌。以Y形嗅觉仪测定了稻纵卷叶螟2—3龄幼虫虫粪、4—5龄幼虫虫粪、健康水稻、稻纵卷叶螟幼虫为害后水稻在纵卷叶螟绒茧蜂对寄主的搜索过程中的作用。结果表明已交配的雌蜂显著趋向稻纵卷叶螟2—3龄幼虫虫粪和4—5龄幼虫虫粪,不趋向健康水稻、稻纵卷叶螟幼虫为害后的水稻。雄蜂、处女雌蜂不显著趋向健康水稻、稻纵卷叶螟幼虫为害后水稻、稻纵卷叶螟2—3龄幼虫虫粪、稻纵卷叶螟4—5龄幼虫虫粪。利用固相微萃取(SPME)及气相色谱/质谱(GC/MS)联用分析稻纵卷叶螟2—3龄幼虫虫粪的化学成分,并通过Y-形嗅觉仪测试已交配雌蜂对稻纵卷叶螟2—3龄幼虫虫粪化学成分标准品的嗅觉反应,结果表明已交配的雌蜂显著趋向1-十一烯和异缬草醛,稻纵卷叶螟幼虫虫粪中的1-十一烯和异缬草醛可能是稻纵卷叶螟绒茧蜂搜索寄主的利他素。Apanteles cypris Nixon is one of the most important natural enemies of the larvae of rice leaf folder,Cnaphalocrocis medinalis Guenée.Through parasitizing their larvae,A.cypris wasps play a major role in biological control of C.medinalis;parasitized host larvae consume less rice leaf than non-parasitized counterparts,thus causing less damage.Previous studies suggest that some parasitoids using chemical cues to locate their hosts.In a tritrophic interaction system consisting of plants,herbivores,and their parasitoids,chemicals released from plants after herbivory are known to help many female parasitoids find their hosts efficiently.Chemical information associated with herbivory can act as an indirect defense for the plant by attracting natural enemies of the host herbivores.There are several potential sources of infochemicals used by parasitoids： the host plant,direct or indirect cues from the host.This study aims to determine if the host searching behavior of A.cypris is affected by volatiles from C.medinalis-infested and uninfested rice plants and frass produced by larvae of C.medinalis.We found that mated female A.cypris were attracted by the frass of 2nd/3rd or 4th/5th instar C.medinalis larvae but not by C.medinalis-infested and uninfested rice plants.In contrast,male and virgin female A.cypris did not respond significantly to any of the stimuli.These results indicate that the mating status of A.cypris females clearly influences their host-searching behavior in response to herbivory-associated chemical information,and we suggest that female parasitoids forage for hosts depending on their own physiological condition in a tritrophic system.To elucidate which chemicals are used by A.cypris to locate their hosts,we analyzed the chemical composition of frass produced by 2nd/3rd instar C.medinalis larvae using solid-phase micro-extraction（SPME） combined with gas chromatography/mass spectrometry（GC/MS）.We collected 23 volatiles from the frass,including terpenoids,alcohols,ketones,amines,aldehyde.Chemical

关 键 词：稻纵卷叶螟绒茧蜂 寄主搜索行为 虫粪 利他素 

分 类 号：S476.3[农业科学—农业昆虫与害虫防治]