The fungitoxic effects of imidacloprid and fipronil on the entomopathogenic fungi Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorok. were evaluated. The colony radial growth and conidial production were measured in the presence of the insecticides added to the culture medium. Imidacloprid was less toxic to the fungi than fipronil, and M. anisopliae was less affected by either insecticide than B. bassiana. The changes in the grooming behavior of Heterotermes tenuis (Hagen) under the action of the insecticides was also evaluated. Using scanning electron microscopy, conidia of B. bassiana and M. anisopliae were observed on the surface of the insect tegument at different times after inoculation. Imidacloprid at sublethal concentrations affected the grooming behavior of H. tenuis, while fipronil did not alter this behavior.
Insecta; entomopathogenic fungi; subterranean termites; control
