昆虫病原菌对桦潜叶蜂协同控制及其与土壤含水量关系

Synergistic control of entomopathogenic microorganisms against Profenusa thomsoni(Hymenoptera:Tenthredinidae)and the dependence on soil water content

[目的]研究首次发现于吉林地区的一种入侵性害虫——桦潜叶蜂的生物防治方法,探索昆虫病原菌协同增效作用最佳发挥组合及条件,为控制该害虫为害及扩散提供技术支持。[方法]通过不同使用剂量苏云金芽孢杆菌和黄绿绿僵菌新西兰变种的复配,筛选对桦潜叶蜂幼虫土壤生活史阶段最敏感微生物菌剂组合体。于桦树林地采用固定样方验证法,对比越冬后未施药对照样方和施药样方桦潜叶蜂成虫羽化量,评价2种生物杀虫菌剂组合对桦潜叶蜂协同控制效果。[结果]苏云金芽孢杆菌与黄绿绿僵菌新西兰变种2∶1、1∶1复配时,对桦潜叶蜂幼虫土壤生活史阶段致死率最高,菌剂协同增效作用最强。土壤含水量与微生物组合菌剂的防治效果呈正相关,土壤相对含水量升高显著提高微生物复合菌剂的防治效果。[结论]生物杀虫菌剂的复配使用能够较好的降低桦潜叶蜂土壤生活史阶段的虫口密度,抑制成虫羽化。适宜土壤含水量增强生物菌剂对桦潜叶蜂越冬幼虫的防效。

[Aims]To study the biological control of Profenusa thomsoni,an invasive pest found in Jilin for the first time,and to explore the optimal combination of synergistic effects and the conditions of the entomopathogenic microorganisms,so as to provide technical support for the control and spread of this pest.[Methods]Screening of the most sensitive combinations of microbiological agents against P.thomsoni larvae in the soil life history stages by combining Bacillus thuringiensis and Metarhizium flavoviride var.novazealandicum at different use doses.In the birch woodland,a fixed sample validation method was used to evaluate the synergistic effect of the combinations against the P.thomsoni.The emergence rate of P.thomsoni of the untreated control plot and the treated plot was compared.[Results]The combinations of B.thuringiensis and M.flavoviride var.novazealandicum at the dose ratio of 2∶1 and 1∶1 had the highest lethality against overwintering larvae of P.thomsoni,with the strongest synergistic effect.Soil water content was positively correlated with the control effect of combination of microbial agents,and elevation of relative soil moisture content significantly increased its control effect.[Conclusions]The compositions of microbiological agents can reduce the population density of P.thomsoni in the soil life history stages and inhibit adult emergence.According to soil ecological adaptability,appropriate soil water content can enhance the control efficacy of the microbiological agents against the overwintering larvae of P.thomsoni.