CONTROL OF Sitophiluszeamais MOTSCHULSKY WITH THIRTEEN OILS OF VEGETABLE AND MINERAL SOURCE

Regina Merino P.¹, Gonzalo Silva A.^1*, J. Concepción Rodríguez M.², AngelLagunes T.², Candelario Santillán-Ortega³, Agustín Robles-Bermúdez³ y Sotero Aguilar-Medel⁴.

ABSTRACT

The maize weevil (SitophiluszeamaisMotschulsky) is a major pest of stored grains. Synthetic insecticides are commonly used to control this pest but problems such as residues in foods and resistance development have required new control alternatives. Thirteen oils in concentrations of 0.5, 1 and 2% (v/w) (volume/weight) were evaluated under laboratory conditions. The evaluated variables in adult were mortality and adult insect emergence and weight loss and seed germination, and in the immature stage adult insect emergence (F₁) and grain weight loss were evaluated. The experiment was conducted in a completely randomized design with five replicates per treatment. The highest adult insect mortality was obtained by almond (Prunusamygdalus L), sunflower (Helianthus annuus L), nut (Juglansregia L.) and soybean (Glycine max L.) oil at 1 and 2% (v/w) with 100% of dead insects. The lowest adult insect emergence was observed in the treatments with grape seed (Vitisvinifera L.), sesame (Sesamumindicum L.) and sunflower oil at 1 and 2% (v/w) with 0% of dead insects. At the immature stage, the lowest F₁ was recorded with the mineral oil at 2% (v/w) with 14% of adult insect emergence. Hazelnut (CorylusavellanaL.), pumpkin (Cucurbitapepo L.), corn (Zea mays L.), groundnut (Arachishypogaea L), sunflower, grape seed, castor (Ricinuscommunis L.), sesame, soybean and mineral oils did not effect maize germination significantly. It was concluded that vegetable and mineral oils have potential for controlling S. zeamais.

Keywords: stored grains, maize weevil, fatty acids.

¹ Departamento de Producción Vegetal, Facultad de Agronomía, Universidad de Concepción, Vicente Méndez 595, Chillán, Chile.

^* Autor para correspondencia E-mail: gosilva@udec.cl

² Programa de Entomología y Acarología, Colegio de Postgraduados, Km 36,5 Carretera México-Texcoco, Montecillo, Estado de México, México.

³ Universidad Autónoma de Nayarit, Unidad Académica de Agricultura, Km. 9 Carr. Fed.  Tepic-Compostela, Xalisco, Nayarit, México.

⁴ Universidad Autónoma del Estado de  México, Centro Universitario Tenancingo, Tenancingo, Estado de México, México.