B型烟粉虱取食诱导的烟草对斜纹夜蛾生长发育和繁殖的影响及机制探讨

Effects of Tobacco Plants Infested by Bemisia tabaci (Gennadius) B-biotype on the Development and Reproduction of Spodoptera litura (Fabricius) and Related Mechanisms

【目的】明确外来入侵害虫B型烟粉虱取食诱导烟草植株对后取食的斜纹夜蛾的防御反应和空间效应,探讨B型烟粉虱取食诱导的烟草防御反应在B型烟粉虱与斜纹夜蛾种间竞争中的作用及机制。【方法】室内采用饲喂寄主叶片的方法,研究B型烟粉虱危害诱导的烟草植株不同部位的叶片对斜纹夜蛾生长发育和繁殖的影响,采用生化分析方法测定烟草植株内相关防御酶的变化。【结果】B型烟粉虱取食诱导的烟草植株叶片对后取食的斜纹夜蛾生长发育、存活和繁殖均产生了不利影响,但处理烟草植株的不同叶位对其影响不同。与取食各自的对照叶片相比,其影响顺序为虫体叶>中间叶>系统白脉叶,各处理与对照间均差异显著;而处理植株的心叶与对照叶片相比对斜纹夜蛾的影响没有明显差异。B型烟粉虱危害的烟草植株叶片与各自的对照叶片相比,虫体叶、中间叶和系统白脉叶中胰蛋白酶抑制剂含量、β-1,3-葡聚糖酶和几丁质酶活性均显著增加,而心叶差异不显著。【结论】B型烟粉虱取食诱导烟草植株叶片对后取食的斜纹夜蛾生长发育和繁殖产生不利的影响,且存在空间系统传导性。B型烟粉虱取食的烟草植株内胰蛋白酶抑制剂含量、β-1,3-葡聚糖酶和几丁质酶活性提高,它们与对斜纹夜蛾的不利影响有关。B型烟粉虱取食诱导的烟草防御反应在对后取食斜纹夜蛾的防御中起重要的作用。

【Objective】The objective of this study is to define defense response of tobacco plants to Spodoptera litura induced by Bemisia tabaci B biotype and their spatial effect,and to explore its role in interspecific competition between B.tabaci and S.litura and its possible mechanism.【Method】The effects of leaves in different positions of tobacco preinfested by B.tabaci B-biotype on growth,development and fecundity of S.litura were investigated by feeding method and the change of related defense enzymes was analyzed using biochemical method in laboratory.【Result】The results showed that tobacco plants preinfested by B.tabaci B-biotype feeding had a negative effect on growth,development and fecundity of S.litura,and different leaf positions of treated plants reacted differently,the sequence was the whitefly-infested leavesthe middle leavesthe white-vein leaves.There were significant differences between treatment and its control.Trypsin protease inhibitor（TPI） content,β-1,3-glucanase activity and chitinase activity in the whitefly-infested leaves,the middle leaves and the white-vein leaves of the treated tobacco plants all increased significantly.The unexpanded leaves showed no significant effect on both the growth,development and fecundity of S.litura and the change of related defense enzymes.【Conclusion】Tobacco preinfested by B.tabaci B-biotype had a negative effect on growth,development and fecundity of S.litura.Furthermore,this effect was systemic and could be transported through the plant.Infestation by B.tabaci B-biotype in tobacco plants led to the higher induction of TPI,β-1,3-glucanase and chitinase,and they may have a correlation with the negative effect on S.litura.The defense responses of tobacco plants induced by B.tabaci B-biotype feeding were considered to play an important role in the host defense against S.litura.