Bioactivity of Brazilian plant extracts on Oncopeltus fasciatus

Abstract

The search for new compounds for developing insecticide agents has stimulated interest in researching natural products from plants. This study aimed to evaluate the potential of extracts obtained from Brazilian plants – Caesalpinia peltophoroides (Fabaceae), “Sibipiruna”; Cecropia catarinensis (Urticaceae), “Embauba”; and Bromelia antiacantha (Bromeliaceae), “Gravata” – as sources of biologically active substances against Oncopeltus fasciatus Dallas (Hemiptera: Lygaeidae), the insect vector of Phytomonas. Oral treatment with C. peltophoroides resulted in 40% mortality rates among nymphs (500 µg/mL) and 100% toxicity in the eggs (500 µg/mL). Oral treatment with crude methanolic extract of C. catarinensis produced 30% nymph mortality, oviposition reduction and 100% inhibition of egg hatching of O. fasciatus, while topical treatment resulted in 47% nymph mortality. Topical treatment with B. antiacantha showed 60% nymph mortality, and toxicity in the eggs (100 µg/mL) of O. fasciatus. These data suggest that the plants studied here can contribute new active compounds for insect control.