桑天牛分泌物及虫粪中的信息化合物对桑天牛卵啮小蜂寄主识别的影响

Effect of Kairomones in Secretion and Faeces of Apriona germari on Host Recognition Behavior of Aprostocetus prolixus

来源于寄主昆虫的信息化合物对寄生蜂的寄主识别和趋性反应有较强的调控作用。桑天牛卵啮小蜂(Aprostocetus prolixus)是桑天牛(Apriona germari)的卵期寄生蜂。初步研究了雌性桑天牛成虫口腔分泌物和产卵后的肛门分泌物以及裸卵等单一信息化合物对桑天牛卵啮小蜂的寄主识别影响,结果表明这些单一信息化合物对该寄生蜂的寄主识别均没有影响。采用有机溶剂萃取法提取桑天牛成虫粪便中的信息类化合物,并且对不同提取溶剂获得的提取液进行了寄生蜂寄主趋性反应和寄主识别行为的测定,结果表明:二氯甲烷溶剂获得的提取液对该寄生蜂的趋性反应有显著影响,正己烷、甲醇、丙酮以及蒸馏水4种溶剂获得的提取液对寄生蜂的趋性反应均无影响;正己烷、二氯甲烷、甲醇3种有机溶剂获得的提取液对寄生蜂的寄主识别行为有影响,证明有机溶剂能够有效提取存在于桑天牛成虫粪便中的该寄生蜂的接触性信息化合物。利用硅胶柱层析的方法对提取液分离纯化,层析液对寄生蜂寄主识别影响的测定结果显示,用正己烷作溶剂的层析液对该寄生蜂的寄主识别有一定的调控作用;而二氯甲烷、甲醇、丙酮和蒸馏水作溶剂的4种层析液则没有调控作用。

Kairomones from host insect have strong regulatory effect on host recognition and taxis response of parasitic wasp. Aprostocetus prolixus is an egg-stage parasitic wasp of mulberry Iongicorn （ Apriona germari）. This study had a primary investigation on the effect of Apriona germari kairomones（including mouthpart secretion, oviposition secretion and bare eggs） on host recognition of the parasitic wasp. It was found that neither the secretion from mouthpart or oviposition nor the bare eggs had any effect on host recognition. After the faeces of Apriona germari were extracted using hexane, dichloromethane, methanol, acetone and distilled water, the extracts were found to have different effect on host recognition. Only dichloromethane extract had significant effect on taxis response of the parasitic wasp. The others had no effect on the taxis response. Hexane extract, dichloromethane extract and methanol extract had effect on host recognition, revealing that organic solvents can extract kairomones from the faeces efficiently. After the extracted liquid were separated and purified with silica gel column chromatography, it was found that the eluate from hexane extract had certain effect on host recognition and those from other four extracts had no effect.