Laboratory evaluation of Beauveria bassiana and Metarhizium anisopliae in the control of Haemaphysalis qinghaiensis in China.

Haemaphysalis qinghaiensis, a prevalent tick species in China, is an ectoparasite that preferentially infests small ruminants and can transmit Theileria sp. and Babesia sp. In this study, we evaluated the pathogenicity of individual and mixed infections of the fungi Beauveria bassiana and Metarhizium anisopliae to H. qinghaiensis nymphs. The estimated LC50 for ticks immersed in solutions of B. bassiana, M. anisopliae and a mixture thereof were: 5.88056 × 10(4), 2.65 × 10(4), and 2.85 × 10(4) conidia mL(-1) respectively, and the nymphal mortality ranged from 52 to 100 %. Thus, these results suggest a potential approach for the biocontrol of H. qinghaiensis.