Field trials of fipronil for control of Rhammatocerus schistocercoides (Rehn, 1906) hopper bands in Brazil

Field trials in the state of Mate Grosso (Brazil) assessed the efficacy of fipronil against Rhammatocerus schistocercoides hopper bands (8th instar) in natural vegetation within the context of a preventive control strategy. Thirteen experimental plots, with 14 hopper bands, were sprayed at doses ranging from 2.15 to 11.8 g a.i./ha. Mortality increased with higher doses in a shorter time, but all tested doses resulted in 100% mortality within one to four days. The dose to control hopper bands depends on the speed of control required, according to the potential threat to crops: preventive control in natural vegetation (4 g a.i./ha) or curative control in crops (8 g a.i./ha dose could be used). (C) 1998 Elsevier Science Ltd. All rights reserved.