Laboratory evaluation of the efficacy of root extracts of Mucuna pruriens (Fabaceae) against the migratory locust, Locusta migratoria (Orthoptera: Acrididae)

The development of environmentally friendly locust control methods has attracted a plethora of attention in recent years. Many products, including botanicals, have thus been extensively evaluated as possible alternatives to the commonly used chemical pesticides, and the search continues. In this study, laboratory tests were undertaken to investigate the efficacy of water/ethanol root extracts of Mucuna pruriens (Fabaceae) against the migratory locust, Locusta migratoria Linné (Orthoptera, Acrididae). Mortality and time to death were used to evaluate the efficacy, and Deltametherin (EC) was considered as a reference standard chemical insecticide. Efficacy of the extracts as contact poisons was determined by direct spraying, topical application and by dipping, whereas stomach action was determined by ingestion of contaminated food. The different bioassays show that the extracts of Mucuna are toxic to the migratory locust and have a potential as substitutes for some of the environmentally hazardous chemical pesticides currently in use for locust control. (Texte intégral