Biological control of locusts and grasshoppers

Control of grasshoppers and locusts has traditionally relied on synthetic i nsecticides, and for emergency situations this is unlikely to change. Howev er, a growing awareness of the environmental issues associated with acridid control as well as the high costs of emergency control are expanding the d emand for biological control. In particular, preventive, integrated control strategies with early interventions will reduce the financial and environm ental costs associated with large-scale plague treatments. The recent devel opment of effective oil formulations of Metarhizium anisopliae spores in Af rica, Australia, and Brazil opens new possibilities for environmentally saf e control operations. Metarhizium biopesticide kills 70%-90% of treated loc usts within 14-20 days, with no measurable impact on nontarget organisms. A n integrated pest management strategy, with an emphasis on the use of Metar hizium, that incorporates rational use of chemical pesticides with biologic al options such as the microsporidian Nosema locustae and the hymenopteran egg parasitoids Scelio spp., has become a realistic option.