十种常用农药与球孢白僵菌的生物学相容性

球孢白僵菌孢子粉与10种常用农药相容性的测定结果显示,随着孢子浓度上升,所试农药对孢子的抑制作用均有不同程度的增强。在1/10田间常规使用浓度下,百菌清和代森锰锌均能抑制或杀死孢子(萌发率<1％)。除阿维菌素外,所有杀虫剂均与白僵菌孢子相容,在常规使用浓度的10倍稀释液中孢子萌发率达90％以上。吡虫啉、蚜虱灵、灭多威和氟虫腈与孢子的相容性最好,其中吡虫啉和蚜虱灵对孢子萌发率的影响不明显随药剂浓度的变化而变化,即使在田间常规使用浓度下孢子萌发率也在95％以上,而阿维菌素与白僵菌的相容性极差。因此,应用白僵菌制剂防治害虫,选择生物学相容性好的农药以低剂量与白僵菌制剂混用,既可使菌剂增效,又可大幅度降低化学药剂用量。

Biological compatibility of ten commercial pesticides with Beauveria bassiana conidia

The compatibility of B. bassiana conidia with 10 widely used pesticides was investigated using 24h liquid culture containing 0.1-1.0 fold of the concentration recommended for field spray. The results showed that negative effects of the pesticides on the germination of B. bassiana conidia increased with the increasing pesticide concentrations. Two fungicides, chlorothalonil 75 % WP and mancozeb 70% WP, killed almost all the conidia of B. bassiana at all concentrations. Five insecticides, including imidacloprid 10% WP, yashiling 22% WP (a mixture of imidacloprid and bupro-fezin) , methomyl 20% EC, triazophos 20% EC, and fipronil 5% FF, exhibited high compatibility with B. bassiana conidia with germination rates exceeding 90% even at the highest concentration. The other two insecticides, chlorfluazuron 5% EC and fenvalerate 20% EC, greatly reduced the germination rate of B. bassiana at the field-spray concentrations recommended but at lower concentration tested the germination rates increased by a big margin. However, abamectin 0.5% EC (a microbial toxin-based insecticide) was highly incompatible with B. bassiana conidia at all the concentrations tested. The results indicate that the compatibility of B. bassiana with commercial pesticides must be taken into consideration when the fungal insecticide was applied. Also, it is possible to choose compatible insecticides at lower rates for enhancing the efficacy of B. bassiana a-gainst insect pests and reducing the input of chemical insecticides.