3种农药对不同虫态赤眼蜂羽化率的影响研究

Study on the effects of three pesticides on the emergence rates of Trichogramma at different develoment stages

为明确田间常用药剂对害虫天敌赤眼蜂羽化率的影响,在室内采用卵卡浸渍法测定了阿维菌素、吡虫啉、吡蚜酮3种农药在田间推荐浓度下对未发育成熟阶段不同虫态稻螟赤眼蜂和螟黄赤眼蜂的羽化率的影响。结果表明,阿维菌素处理卵、幼虫、预蛹及蛹4种虫态赤眼蜂后,其羽化率均显著下降。其中,稻螟赤眼蜂羽化率为24.77%~43.99%,螟黄赤眼蜂羽化率为35.00%~39.15%,对赤眼蜂的安全性风险较高;而吡虫啉和吡蚜酮2种农药处理对2种赤眼蜂的羽化率均无明显影响,羽化率均在93%以上,对赤眼蜂非成蜂期的安全性风险较低。因此,在赤眼蜂释放后应禁止使用阿维菌素,成蜂寄生后可使用吡虫啉和吡蚜酮。

In order to clarify the effects of commonly used pesticides on parasitoid wasps Trichogramma,the emergence rates of T.japonicum and T.chilonis after treated with avermectin,imidacloprid and pymetrozine at different develoment stages,were determined indoors by egg card impregnation method.The results showed that after treatment with avermectin at egg,larva,prepupa and pupa stages,the emergence rates of parasitoid wasps were significantly decreased.The emergence rates of avermectin on T.japonicum and T.chilonis were 24.77%-43.99%and 35.00%-39.15%,respectively.Avermectin had high safety risks to Trichogramma at immature stages.Imidacloprid and pymetrozin had low risks to Trichogramma,with the emergence rates above 93.82%.Therefore,the application of avermectin should be prohibited after releasing Trichogramma,while imidacloprid and pymetrozine could be used.