核型多角体病毒与侧沟茧蜂对斜纹夜蛾幼虫的协同作用

研究了斜纹夜蛾幼虫体内的斜纹夜蛾侧沟茧蜂存活率、发育历期、寄主感染病毒时间、病毒浓度之间的关系，并测定了斜纹夜蛾侧沟茧蜂的传毒效率．结果表明，病毒对寄主体内寄生蜂历期无明显影响，寄生在幼虫体内的寄生蜂能在寄主病死前完成发育，存活比例因寄主感染病毒的时间和浓度而异．斜纹夜蛾被寄生后接种病毒(SINPV)，距离寄生时间越长，饲毒浓度越低，寄生蜂完成发育的比例越大，但饲毒时间是主要影响因素．从感病幼虫体内发育成的侧沟茧蜂或曾经在感病寄主上产过卵的寄生蜂，以及通过人工方式使产卵器被病毒污染的寄生蜂，均能携带一定数量的病毒．通过产卵活动，侧沟茧蜂成蜂能在寄主幼虫个体间传递病毒．当寄生蜂在感病的寄主幼虫上产卵带毒后，平均可传递病毒给2．14头幼虫；发育于感病幼虫体内的寄生蜂，平均可传递病毒给2．45头幼虫．通过用病毒液浸茧或用混有病毒的蜂蜜饲喂成蜂等方式使产卵器污染病毒的寄生蜂，传毒效率随饲毒浓度增加而提高，平均可传递病毒1．45头和0．94头幼虫

Cooperative effect of Spodoptera litura nuclear polyhedrosis virus with parasite wasp,Microplitis sp.On the S.Litura larvae

The relationship between the survival rate, developmental duration of Microplitis sp. in Spodoptera litura larvae and time of exposure of the host larvae to virus, the inoculation virus concentration were investigated to determined if parasites which emerged from virus-infected S.litura larvae had normal survive, and if the parasites could sever as the vector for S.litura nuclear polyhedrosis virus (SlNPV). There was no significant difference in time that parasites spent in virus-infected larvae and healthy one, indicating the SlNPV did not affect the developmental period of Microplitis sp. Parasite larvae in hosts exposed to virus after parasitization compmeted their development before their hosts died of virus infection. The proportion of parasites survived varied with the inoculation virus concentration and the time of exposure of the host larvae to virus, the percent of parasites survived increased as the time between host parasitization and host virus exposure increased, and decreased as the inoculation virus concentrations increased. The female parasites which developed or oviposited in virus-infected hosts, and manually contaminated the ovipositor of the females with virus suspension could all carry infective doses of the virus, and transmit virus from infected larvae to healthy one through ovipositor. A female parasite which developed or oviposited in virus-infected hosts transmitted infective doses of the virus to an average of 2.14, 2.45 healthy host larvae exposed to it respectively. A female parasite from the cocoon contaminated with SlNPV of different virus concentration could transfer infective doses of the virus to an average of 1.45 healthy host larvae.A female parasite exposed to the mixture of different virus concentration and 10% honey-water solution could also transmit virus to an average of 0.94 larva.