Abstract

OLIVEIRA, José V.  and  VENDRAMIM, José D.. Repellency of essencial oils and powders from plants on adults of Zabrotes subfasciatus (Boh.) (Coleoptera: Bruchidae) on bean seeds. An. Soc. Entomol. Bras. [online]. 1999, vol.28, n.3, pp. 549-555. ISSN 0301-8059.  http://dx.doi.org/10.1590/S0301-80591999000300026.

The repellent effect of essential oils and powders from plants on Zabrotes subfasciatus (Boh.) (Coleoptera: Bruchidae) was studied on bean seeds. The number of attracted insects was reduced, and the repellency percentages increased directly with the doses and concentrations of the products used. Cinnamon leaf oil (Cinnamomum zeylanicum Ness) showed repellency percentages of 63.5; 85.4, and 96.2% at 0.5; 2.5, and 5.0 ml/kg of seeds, respectively; the repellency percentages of neem seed oil (Azadirachta indica A. Juss) were 29.6; 76.7, and 89.4%, respectively at the same doses. At 0.5 and 2.5 ml/kg, the repellency percentages of laurel leaf oil (Laurus nobilis L.) were 62.0 and 74.6, respectively. The powders were less repellent than the oils, except for laurel leaf powder at 2.5 and 5.0% with 93.7 and 92.9% of repellency, respectively, followed by cinnamon (51.0; 62.3%), and black peper, Piper nigrum L., (35.9; 45.4). The results showed that the cinnamon, laurel, and neem oils, as well as the laurel leaf powder are promising products for alternative control of Z. subfasciatus in stored bean.

Keywords : Insecta; bean weevil; natural insecticide; stored bean pest.