ACTIVIDAD INSECTICIDA DE Melia azedarach L. (MELIACEAE) SOBRE Sitophilus zeamais Motschulsky (COLEOPTERA: CURCULIONIDAE)

Abstract

e maize weevil (Sitophilus zeamais Motschulsky) is considered a worldwide pest of stored products and its control is usually performed with synthetic insecticides. The insecticidal and repellent properties of powder of Melia azedarach L. (Meliaceae) leaves, fruits and woody stems in concentrations of 0.5, 1.0 and 2.0% (w/w) against S. zeamais were evaluated under laboratory conditions. The highest mortality as contact insecticide was obtained with fruit and leaf powder at 2% with 91% of mortality. Significant fumigant activity was not observed because no treatment exceeded 30% of mortality. Powder of the three vegetal structures showed repellent effect but the highest activity was observed in the powder of leaves. Finally, the powder of woody stems affected wheat germination. Thus M. azedarach powder has a great potential to control S. zeamais.