球孢白僵菌与11种新型化学杀菌剂的相容性评价

本研究测定了当前市场上常用的11种化学杀菌剂对球孢白僵菌HFW-05萌发、生长速率、产孢量、胞外蛋白酶产生水平及杀虫活性的影响。结果表明，常规浓度下，除68.75%氟菌霜霉威对菌株HFW-05菌丝生长没有抑制作用、50%啶酰菌胺对菌株HFW-05产孢量没有抑制作用外，其余杀菌剂对HFW-05孢子萌发、菌丝生长、产孢量和胞外蛋白酶产生水平均有显著抑制作用。60%唑醚代森联对菌株HFW-05的抑制作用最强，常规浓度、5倍稀释和10倍稀释浓度下均显著抑制菌株HFW-05孢子萌发、菌丝生长、产孢量及胞外蛋白酶的产生。多数杀菌剂随处理浓度的降低和时间推移对菌株HFW-05的抑制作用逐渐减弱。白僵菌-杀菌剂同时使用时，42.4%唑醚氟酰胺、10%苯醚甲环唑和50%咯菌腈没有降低HFW-05的杀虫活性，小菜蛾2龄幼虫的校正死亡率和僵虫率与单独使用菌株HFW-05差异均不显著；25%双炔酰菌胺、50%啶酰菌胺、50%烯酰吗啉、68.75%氟菌霜霉威、50%醚菌酯、60%唑醚代森联和32.5%苯甲嘧菌酯则显著降低了菌株HFW-05对小菜蛾2龄幼虫的杀虫活性，其中60%唑醚代森联对菌株HFW-05的致病力影响最大，对小菜蛾2龄幼虫的校正死亡率降低了49.9%；25%吡唑醚菌酯对小菜蛾2龄幼虫有一定致死作用，校正死亡率为46.2%，与菌株HFW-05同时使用时小菜蛾2龄幼虫的校正死亡率提高了20%。

Compatibility of Beauveria bassiana with 11 Chemical Fungicides under Laboratory Conditions

Effects of 11 chemical fungicides commonly used in the field on spore germination, growth rate, spore production, the extracellular protease and pathogenecity of Beauveria bassiana strain HFW-05 were determined under laboratory conditions. Almost all the tested fungicides significantly inhibited spore germination, mycelium growth, spore production and enzymatic activity at conventional concentrations. Among them, 68.75% fluopicolide propamocab hydrochloride and 50% boscalid didn't show negative effect on mycelium growth or spore germination at conventional concentrations. The 60% yl-ethyl metiram showed the highest inhibition against HFW-05 with no spore germination or mycelium growth at three test concentrations. The inhibition by most of the fungicides is concentration dependent. Bioassay results showed that 42.4% fluxapyroxad, 10% difenoconazole and 50% fludioxonil did not reduce activity of HFW-05 against Plutella xylostella 2nd instar larvae. But 25% mandipropamid, 50% boscalid, 50% dimethomorph, 68.75% fluopicolide propamocab hydrochloride, 50% kresoxim-methyl, 60% yl-ethyl metiram and 32.5% difenoconazole azoxystrobin significantly reduced the efficacy against P. xylostella larvae. 60% yl-ethyl metiram was the most harmful chemical fungicide to HFW-05, which reduced the corrected mortality of P. xylostella larvae by 49.9% in comparison with that obtained with HFW-05 only. 25% pyraclostrobin showed insecticidal activity to P. xylostella larvae with corrected mortality of 46.2%, which was increased by 20% when pyraclostrobin was mixed with HFW-05.