Laboratory evaluation of the pathogenicity of three isolates of the entomopathogenic fungus Beauveria bassiana (Bals.) vuillemin on the American cockroach (Periplaneta americana)

Mycopesticides can be ideal for the biocontrol of cockroaches because rite habitat of these insects promotes initial fungal infection and its subseque nt spread The pathogenicity of three isolates of Beauveria bassiana to the American cockroach was tested. The insects were treated in three different ways, by direct contact with spore mass, a spore wheat flour mixture and a spray of an aqueous spore suspension. A mortality of 100% in the first trea tment, 67-100% in the second treatment and 17-75% in the third treatment wa s observed. These results suggest that B. bassiana spore formulations in fo od baits can be developed for cockroaches.