Toxicidade do óleo essencial de Schinus terebinthifolius (anacardiaceae) para Thaumastocoris peregrinus (Heteroptera : thaumastocoridae)

Abstract

Out of the products with botanical origins, the essential oils have been standing out due their high volatile characteristic and low persistence in the environment, implying in less contamination, besides not affecting other organisms that are not targeted. Schinus terebinthifolius is a tree of the Anacardiaceae family, typical of the Brazilian seashore vegetation, being its use emphasized on its anti-inflammatory, healing, astringent, anti-thermal, antimicrobial and insecticide properties. In order to contribute to the alternative forms for the pest control, this study aimed to evaluate the toxicity of S. terebinthifolius essential oil to Thaumastocoris peregrinus, an exotic pest of eucalyptus. The toxicity bioassays were conducted in plastic cups (500mL) containing 10 adult unsexed bugs, which were nebulized with solutions of S. terebinthifolius, at concentrations of 5, 10, 15 and 20% being the acetate the control treatment. Evaluations occurred seven days after the applications, for the determination of lethal times (TL50 and TL90) and lethal concentrations (LC50 and CL90). The experimental design was completely randomized with five replicates. The TL50 and TL90 both presented temporal variation from 24 to 48 hours. The insects showed a high sensitivity to oil, being the concentrations of 15 and 20% the ones who caused highest mortality of bedbugs in 24hours, thus confirming the insecticidal activity of S. terebinthifolius.