Efficacy of Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and diatomaceous earth against Periplaneta americana L. (Dictyoptera: Blattidae)

The entomopathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and diatomaceous earth formulation SilicoSec was evaluated alone and in combination against adult Periplaneta americana L. (Dictyoptera: Blattidae) in the laboratory. The fungus solution was applied topically on the first abdominal segment at dose rate of 15, 30, 45 and 60 ppm alone or in combination with SilicoSec at 1, 2, 3 and 4 gm/m². The mortality of the exposed individuals was recorded after 7, 14 and 21 d of exposure. The mortality of the adults after 14 d of exposure was significantly higher in case of the highest dose rates of M. anisopliae with SilicoSec than that of SilicoSec or M. anisopliae applied alone. The results of the present study clearly indicate that the entomopathogenic fungi and diatomaceous earth can play vital role in eco-friendly control of cockroaches.