江淮棉区棉大卷叶螟主要寄生性天敌的寄生作用

Identification and behaviors of parasitoids of Sylepta derogata in the Yangtze River and Huihe Valley

通过大田调查与室内饲养观察结果表明,江淮棉区棉大卷叶螟Sylepta derogataFabricius的主要寄生蜂(蝇)有7种:卷叶螟绒茧蜂Apanteles derogatae(Watanabe)、叶卷蚁形蜂Goniozus japonicus(Ashmead)、卷叶螟姬小蜂Sympiesissp.、菲岛扁股小蜂Elasmus philippinensis(Ashmead)、广黑点瘤姬蜂Xanthopimplapunctata(Fabricius)、广大腿小蜂Brachymeria lasus(Walker)和玉米螟厉寄蝇Lydella grisescens(Robineau-Desvoidy)。其中,卷叶螟绒茧蜂和卷叶螟姬小蜂为棉大卷叶螟幼虫期优势寄生蜂种,广大腿小蜂为幼虫-蛹跨期优势寄生性天敌。自然情况下,棉大卷叶螟的被寄生率高达25.7%,寄生性天敌对棉大卷叶螟种群起着重要的控制作用。

A survey of parasitoids of the cotton leaf-roller, Sylepta derogata Fabricius, in the cotton fields of the Yangtze River and Huihe River Valley was conducted by both field sampling and laboratory rearing. The following seven species of parasitoids were recorded ： Apanteles derogatae （ Watanabe ）, Goniozus japonicus （ Ashmead ）, Sympiesis sp., Elasmus philippinensis （Ashmead） , Xanthopimpla punctata （ F abricius ） , Brachymeria lasus （Walker） and Lydella grisescens （Robineau-Desvoidy）. Among them, A. derogatae and Sympiesis sp. were the dominant species of the larval stage. B. /astts was the dominant species of the larvae-pupae period. The rate of parasitism of cotton leaf-roller reached up to 25.7% in the field. These parasitoids seemed to play an important role in suppressing the population of the cotton leaf-roller.