杀菌剂对感染越冬桃小食心虫的白僵菌的抑制作用

【目的】桃小食心虫是我国果树上发生最普遍的食心类害虫,其室内人工饲养是综合防治研究的基础,但面临着田间越冬种群大量感染白僵菌死亡,给实验室种群的建立带来很大困难。因此筛选出对球孢白僵菌高效的杀菌剂用于解决桃小食心虫种群建立时感染白僵菌的问题。【方法】利用液体摇床振荡法和平皿十字交叉法测定16种常见杀菌剂对球孢白僵菌孢子萌发和菌丝生长的影响。【结果】筛选出9种杀菌剂,其中,腐霉利和中生菌素对孢子萌发的抑制效果好,常规用量抑制效果分别为97.88%±1.53%和93.22%±2.36%;抑霉唑和戊唑醇对菌丝生长的抑制效果明显,常规用量抑制效果分别达100.00%±0.00%和98.43%±0.99%;咪酰胺、丙环唑、噻菌灵、腈菌唑和吡唑醚菌酯对孢子萌发和菌丝生长的抑制效果都好。同时测定了这9种杀菌剂常规浓度及其5倍和10倍稀释液对桃小食心虫的毒力,结果表明有5种杀菌剂对桃小食心虫稍有不利影响。【结论】4种杀菌剂,中生菌素、戊唑醇、吡唑醚菌酯和噻菌灵可用于解决桃小食心虫种群建立时越冬幼虫的感染白僵菌问题。

Inhibitory function of fungicides on Beauveria bassiana in peach fruit moth overwintering stage

Objective] Carposina niponensis Walsingham is an important pest in Chinese orchard and causes wide host and area damage. Artificial feeding of C. niponensis is the basis of research and integrated control, meanwhile Beauveria bassiana is a main pathogen to overwintering larvae C. niponensis and brings great difficulties to establish laboratory population. So our objectives is to screen fungicides which have good inhibition effect to control B. bassiana in large-scale feeding C. niponensis. Methods] Liquid shaker shock method and plates cross bracketing method were used to evaluate the effect of 16 common fungicides on spore germination and hyphal growth of B. bassiana. Results] We screened 9 fungicides which had good inhibitory effect on B. bassiana, in which Procymidone and Zhongshengmycin were good at spore germination inhibitory, and inhibitory rate were 97.88%±1.53% and 93.22%±2.36% at recommended concentration. While, Imazalil and Tebuconazole have obvious inhibition effect on hyphal growth, and inhibitory rates were 100.00%±0.00% and 98.43%±0.99%. But 5 fungicides (Prochloraz, Propiconazole, Thiabendazole, Myclobutanil, Pyraclostrobin) had good effect on both spore germination and hyphal growth. In addition, we evaluated mortality of C. niponensis at different concentrations (recommend concentration, 5-fold recommend concentrations, 10-fold recommend concentration) to investigate negative impact of 9 fungicides on C. niponensis Walsingham, The results showed that 5 fungicides have slightly adverse impact on C. niponensis. Conclusion] Zhongshengmycin, Tebuconazole, Pyraclostrobin and Thiabendazole can be used to control B. bassiana infection in large-scale feeding C. niponensis.