不同品系昆虫病原线虫对蜂巢小甲虫的致病力研究

Effects Evaluation of Different Entomopathogenic Nematode Strains Against Aethina tumida(Coleoptera:Nitidulidae)

为明确市售昆虫病原线虫制剂对蜂巢小甲虫(Aethina tumida)幼虫和蛹的致病力,为该害虫的防治提供新的技术措施,室内采用浸渍法、土壤法测定了5种不同品系昆虫病原线虫对蜂巢小甲虫末龄老熟幼虫和蛹的致病力,采用土壤法测定了小卷蛾斯氏线虫(Steinernema carpocapsae All)不同施用时间、不同施用剂量对蜂巢小甲虫幼虫致病力的影响。浸渍法生物测定结果表明,5种不同品系昆虫病原线虫对蜂巢小甲虫幼虫的致病力差异很大,其中小卷蛾斯氏线虫All侵染4 d、12 d后,蜂巢小甲虫幼虫的校正死亡率分别为67.50%±0.05%和72.36%±3.14%,均显著高于其他品系。土壤法生物测定结果表明,昆虫病原线虫对蜂巢小甲虫幼虫具有明显的致死作用,其中小卷蛾斯氏线虫All对蜂巢小甲虫幼虫的侵染效果达100%,显著高于其他线虫品系。蜂巢小甲虫幼虫入土后,按不同时间顺序施用小卷蛾斯氏线虫All,结果表明14 d前施用均能取得良好的防治效果。侵染期线虫小卷蛾斯氏线虫All与蜂巢小甲虫幼虫数量之比大于213∶1时,防治效果最佳。因此小卷蛾斯氏线虫All具有防治蜂巢小甲虫的潜力,可在发生蜂巢小甲虫危害的蜂场推荐使用。

This study aims to evaluate the pathogenicity of commercially available entomopathogenic nematodes against Aethina tumida larvae and pupa,thus develop a new agricultural method to control A.tumida beetle.The pathogenicity of 5 strains of entomopathogenic nematodes(EPNs)against wandering larvae and pupae of A.tumida were determined by the dipping and sand bioassays in the laboratory,respectively.In addition,the influence of different application time and dosage on the virulence of Steinernema carpocapsae All to A.tumida larvae was tested by sand bioassays under laboratory condition.The dipping bioassay results showed that the pathogenicity of 5 EPNs strains against A.tumida larvae was different under laboratory condition.The infection incubation of S.carpocapsae All against A.tumida larvae was the highest.The corrected mortality rate of A.tumida larvae infected by S.carpocapsae All were 67.50%±0.05%and 2.36%±3.14%after 4 d and 12 d,respectively,which was higher than that of other EPNs.The sand bioassay result demonstrated a significant treatment effect on A.tumida mortality when compared to the control.The S.carpocapsae All provided excellent control with 100%mortality of A.tumida larvae being obtained,which showed significantly higher mortality than A.tumida larvae exposed to any other nematode strains.Sequential applications of the nematodes following larvae entering sand also provided excellent control before 14 d application.The optimal control effect would be achieved when the ratio of S.carpocapsae All to A.tumida was more than 213∶1.So entomopathogenic nematodes S.carpocapsae All has a potential to control A.tumida larvae and pupae,it could be recommended for use in apiary where A.tumida occurred.