南方小花蝽触角感器的扫描电镜观察

Observations on antennal sensilla of Orius similis Zheng with scanning electron microscopy

南方小花蝽Orius similis Zheng捕食能力较强,对田间多种小型害虫有明显的控制作用,是一类重要的捕食性天敌。本文利用扫描电镜分别对新羽化的南方小花蝽雌、雄成虫和5龄若虫的触角形态和感器进行了观察。结果发现,南方小花蝽雌、雄成虫以及5龄若虫触角均为线状,共4节,分为柄节、梗节和鞭节。触角上共有5种感器,分别为毛形感器、刺形感器、锥形感器、具弯钩形感器和耳形感器,其中毛形、刺形感器各有2个类型,耳形感器是首次在蝽类昆虫触角上发现。雌、雄成虫的触角存在性二型现象,雄成虫触角感器数量明显多于雌成虫;若虫的感器类型及数量比成虫少。不同类型的感器在触角各节上的数量与分布各不相同。本文以期深入了解其化学感受系统,为揭示南方小花蝽的寄主选择行为机制提供基础。

Orius similis Zheng （Hemiptera：Anthocoridae） is an important predator of the pests in fields with high predatory abilityThe antennae of newly emerged females, males and 5th instar nymphs were observed respectively with a scanning electron microscopeThe antenna of Osimilis adults and nymphs were filiform and it was divided into scape, pedicel and flagellum There were five kinds of sensilla on the antennae： sensilla trichodea, sensilla chaetica, sensilla basiconaca, sensilla bent-tipped and sensilla auricillicaBoth of sensilla trichodea and sensilla chaetica could be divided into two typesThe sensilla auricillica was first found in the Hemipterous insects Sexual dimorphism in adult sensilla was apparent Males had significantly more sensilla than females and 5th instar nymphs were less than adults The quantity and distribution of each kind of sensillum differed in different segments of the antennaThe results provided the basic for understanding their chemical sensory sensila and revealing the host selection behavioral mechanism of Osimilis.