Dennettia Oil, a Potential New Insecticide: Tests with Adults and Nymphs of Periplaneta americana and Zonocerus variegatus12

Abstract

In assessing potential insecticidal activity of the essential oil of Dennettia tripetala G. Baker (Anonaceae), samples of the oil obtained by steam distillation from the edible fruits were tested against nymphs and adults of the American cockroach, Periplaneta americana (L.), and a grasshopper, Zonocerus variegatus (L.). For comparative assessment, diazinon, lindane, and propoxur also were tested. Graded vol/vol dilutions in acetone of the various compounds were used for the tests, and testing was by the contact method, employing the treated surface exposure technique and the topical application technique. Irrespective of species, stage of development, or exposure technique, dennettia oil was significantly more toxic to all the insects than the other 3 compounds.