[Teflubenzuron toxicity on larvae of the fifth stage Locusta migratoria cinerascens [Fabricius, 1781] [Orthoptera: Acrididae]]

The larvicidal activity of teflebenzuron [TFB benzoylphenylurea] was evaluated on the 5[th] instars larvae of Locusta migratoria cinerascens, newly emerged. This product was administered by ingestion at the following doses: 2.5, 5, 10, 15, 20 and 25 microg/larvae. Results obtained show that this product has good larvicidal activity. All tested doses were lethal, death occurs during the moult in the treated series. The activity of TFB on the structural parameters of the cuticle showed a significant reduction in chitin content and an increase cuticular protein in treated series. This product may therefore play a particularly important role in locust areas where barriers treatments are recommended.