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

Abstract:

[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.