INSECTICIDAL EFFECTIVENESS OF MAMMEA-AMERICANA (GUTTIFERAE) EXTRACTS ON LARVAE OF DIABROTICA-VIRGIFERA-VIRGIFERA (COLEOPTERA, CHRYSOMELIDAE) AND TRICHOPLUSIA-NI (LEPIDOPTERA, NOCTUIDAE)

Seed and leaf extracts of Mammea americana (mamey apple) have a histor ical use as a biopesticide with the active components previously chara cterized. We reexamined the utility of this natural bioinsecticide in light of existing sources of material as a by-product of the fruit pro cessing industry. Our results add Diabrotica virgifera virgifera and T richoplusia ni to the list of insects which are susceptible to the ins ecticidal ingredients of M. americana and confirms earlier reports of activity against Blatella germanica, Periplaneta americana, and Plutel la xylostella. We report LD50s for crude hexane extracts of M. america na leaves and seeds against T. ni. These materials represent renewable sources of bioinsecticides for agriculture, and should regenerate int erest in coumarin-type compounds for novel pesticidal action.