东亚小花蝽触角的扫描电镜观察

东亚小花蝽Orius sauteri(Poppius)是我国北方小型农林害虫的重要捕食性天敌昆虫,在天敌昆虫生产及防治害虫应用上具有较大价值。为了深入了解其化学感受系统,揭示东亚小花蝽的捕食行为机制,有必要对其触角结构及感器进行超微结构分析。本研究应用扫描电镜技术观察了东亚小花蝽1~5龄若虫及雌、雄成虫触角的结构和感器的类型、分布及超微结构。结果表明,东亚小花蝽1~5龄若虫及雌、雄成虫触角均为线状,分为柄节、梗节和鞭节(2亚节),随着东亚小花蝽生长发育,触角总长度及各节长度均显著增加,各节直径的增加不显著。东亚小花蝽触角上有5种感器,分别为毛形感器、刺形感器、锥形感器、具弯钩形感器和钟形感器,其中毛形感器和刺形感器各有2种亚型,钟形感器仅在1龄若虫触角上存在,2~5龄若虫及成虫触角上该感器退化消失。雄成虫触角感器数量明显多于雌成虫,若虫感器数量比成虫少。不同类型的感器在触角各节上的数量与分布各不相同。东亚小花蝽触角大小和感器的种类及数量随生长发育而变化,成虫触角感器存在性二型现象。

Scanning Electron Microscope Observations of Antenna of Orius sauteri (Poppius)

In northern China,Orius sauteri (Poppius) (Hemiptera:Anthocoridae) is an important predator of the small agriculture and forestry insect pests,and is of great potential for mass production and field application.The structure and sensilla (types,distributions and ultrastructures) of the antenna of nymphs (1-5 instar),adult females and males of O.sauteri were observed under the scanning electron microscope (SEM).Antenna of O.sauteri nymphs (1-5 instar) and adults were of filiform and divided into four parts,one scape,one pedicel and two flagellums (flagellum Ⅰ and Ⅱ).With the increase ofinstar,lengths of O.sauteri antenna and each part increased significantly,but diameters of each part increased non-significantly.Five kinds of sensors existed on O.sauteri,including sensilla trichodea,sensilla chaetica,sensilla basiconca,sensilla bent-tipped and sensilla campaniformia.Both sensilla chaetica and sensilla basiconica contained two subtypes,respectively.The sensilla campaniformia only existed on 1 st instar nymph.Males had significantly more sensillas than females,and nymphs harbored fewer than adults.The quantity and distribution of each kind of sensillum differed between segments of the antenna.Antenna size,sensilla type and quantity changed with O.sauteri development.Sexual dimorphism in sensilla was also apparent.