[目的]测定蜡蚧轮枝菌MZ041024菌株对南瓜实蝇各虫态的室内毒力,为利用蜡蚧轮枝菌进行生物防治提供理论依据.[方法]以南瓜实蝇的幼虫、成虫和蛹为目标昆虫,利用3.0×104、3.0×105、3.0×106、3.0×107、3.0×108个孢子/mL 5个浓度的蜡蚧轮枝菌MZ041024菌株分生孢子液对其进行室内毒力测定.[结果]蜡蚧轮枝菌MZ041024菌株在室内对南瓜实蝇幼虫、成虫和蛹具有较强的毒力,其中在3.0×108个孢子/mL浓度下南瓜实蝇各虫态的死亡率均达最高,幼虫的校正死亡率为(80.1 1±1.32)%、LT50为4.513±0.359 d、第9d的LC50为(2.907±0.495)×104个孢子、mL;成虫的校正死亡率为(87.78±1.11)%、LT50为3.585±0.385 d、第9d的LC50为(2.366±0.579)×104个孢子/mL;蛹的校正死亡率为(81.11±2.94)%、LT50为4.152±0.289 d,第9d的LC50为(2.495±0.375)× 104个孢子/mL.[结论]蜡蚧轮枝菌MZ041024菌株在室内对南瓜实蝇各虫态均有一定毒力,对各虫态毒力大小表现为成虫>蛹>幼虫;高浓度的蜡蚧轮枝菌分生孢子液对南瓜实蝇的防治效果优于低浓度的防治效果.
[Objective]The virulence of Verticillium lecanii MZ041024 against the larvae, adults and pupae of Bac- trocera tau in laboratory was detected to provide theoretical references for the biological control of Verticillium lecaniL [Method ]Larvae, adults and pupae of Bactrocera tan were targeted. The virulence of Verticillium lecanii isolates MZ041024 under five different concentrations ( 3.0×104, 3.0× 105, 3.0×106, 3.0 ×107, 3.0×10^8pores/mL) was studied in laboratory. [Result]The MZ041024 strain had considerable virulence against the larvae, adults and pupae of Bactrucera tan in labora- tory. Death rate was the highest at every stage of Bactrocera tau at the concentration of 3.0~10s spores/mL. The corrected death rate of 3.0xl0s spores/mL against larvae was (80.11±1.32)%, and the median lethal time (LTso) of this concentra- tion was (4.513±0.359)d. The median lethal concentration (LC50 of the ninth day after treatment was (2.907±0.495)× 104 sporesJmL. The corrected death rate of adult was (87.78±1.11)%, and the median lethal time (LT50)of this concentration was (3.585±0.385)d. The median lethal concentration (LC50) of the ninth day after treatment was (2.366±0.579)×104 spores/ mL; The corrected death rate of pupae was (81.11±2.94)%, and the median lethal time (LTso) of this concentration was (4.152±0.289)d. The median lethal concentration (LCso) of the ninth day after treatment was (2.495±0.375)×104 spores/mL. [Conclusion]The virulence sequence of Verticillium lecanii to Bactrocera tau was adults〉 larvae 〉pupae. Ver- ticillium leeanii was virulent to Bactrocera tan at all stages. Verticillium lecanii solution at higher concentration was superior to that at lower concentration regarding the control and prevention of Bactrocera tau.