Evaluation of the effect of Heterorhabditis bacteriophora (HP88) on Stomoxys calcitrans (Linnaeus, 1758) larvae (Diptera: Muscidae) in sugarcane bagasse ash.

The purpose of this study was to evaluate the effect of the EPN Heterorhabditis bacteriophora HP88 on Stmoxys. calcitrans larvae in sugarcane bagasse ash. Groups of 10 stable fly larvae were placed in Petri dishes containing filter paper and bagasse ash. Concentrations of 50, 150 and 250 EPNs/larva of S. calcitrans in four milliliters of distilled water were added to each plate. In the control group contained only distilled water, without EPNs. The bioassay had three replications and was maintained at 27 ± 1°C and 70-80% relative humidity. It was observed that mortality rate in all treated groups was significantly higher than in the control group (26,6%). The mortality rate in the presence of 50 EPNs/larva (46,6%) was lower than in 150 EPNs/larva (76,3%), which in turn was lower than 250 EPNs/larva group (93,3%). It was verified by analysis of variance and regression that there was a linear pattern of mortality, that is, the higher the EPNs/larva concentration, the higher the larval mortality. It was concluded that EPN H. bacteriophora HP88 was capable of infecting and causing mortality of stable fly larvae in sugarcane bagasse ash.