Effects of Essential Oils From Five Plant Species Against the Granary Weevils Sitophilus Zeamais and Acanthoscelides Obtectus (Coleóptera)

Abstract

Essential oils obtained from Gomortega keule, Laurelia sempervirens, Origanum vulgare, Eucalyptus globulus, and Thymus vulgaris were analyzed by gas chromatography and gas chromatography-mass spectrometry and evaluated for their toxicity against adults of Sitophilus zeamais (Motschulky) and Acanthoscelides obtectus (Say) (Coleoptera). Contact toxicity was assayed by impregnating filter paper discs with the oils. The amount of essential oils applied in each desiccator (4 l capacity) was 4, 8, 16, or 32 µl, corresponding to 1, 2, 4, or 8 µl/l air. The results showed significant differences between the tested dosages and exposure periods of the essential oils. Although desirable insecticidal activities against A. obtectus were achieved with the essential oils of all five plants, the oils from G. keule and L. sempervirens were the most effective at 96 h. On the other hand, the essential oils of E. globulus and T. vulgaris were most effective against S. zeamais. In all plant species, higher doses or longer exposure periods were more effective against both insects. No mortality was observed in the control group (acetone only) of each species. Therefore, these results suggest that essential oils from the studied plants may be used against insect pests in grain storage.

Bioactivity of Peumus boldus Molina, Laurelia sempervirens (Ruiz & Pav.) Tul. and Laureliopsis philippiana (Looser) Schodde (Monimiacea) essential oils against Sitophilus zeamais Motschulsky

“…Ascaridole, as one of the most abundant components agrees with the results of Bittner et al (2008) and Niemeyer and Teillier (2007) who documented concentrations as high as 38.9% and 60.3%, respectively. However, Urzúa et al (2010) considered that 1,8-cineole was the main component (36.62%) of P. boldus.…”

“…For example, Urzúa et al (2010) found insecticidal properties of P. boldus essential oil against Musca domestica L. and Bittner et al (2008) and Betancur et al (2010) indicated that this oil showed insecticidal activity against S. zeamais and Acanthoscelides obtectus. But the Monimiaceae family has other two native plants from Chile, Laurelia sempervirens (Ruiz & Pav.)…”

VARIACIÓN ESTACIONAL DE LA REPELENCIA DE LOS ACEITES ESENCIALES DE MONIMIACEAE SOBRE Sitophilus zeamais Motschulsky (CURCULIONIDAE)

“…Los mejores resultados de control se han obtenido con plantas aromáticas, en especial de la familia Monimiaceae (Bittner et al, 2008). En Chile, esta familia tiene solo tres especies nativas: Peumus boldus Molina (boldo), Laurelia sempervirens (Ruiz et Pau.)…”

“…Tul (laurel) y Laureliopsis philippiana Looser (tepa) (Rodríguez et al, 2005). Bittner et al (2008) y Betancur et al (2010) describieron el efecto insecticida de contacto y fumigante además de actividad repelente del aceite esencial de P. boldus contra S. zeamais y Acanthoscelides obtectus (Say) (Bruchidae). Bittner et al (2008) y Zapata y Smagghe (2010), encontraron que el aceite esencial de L. sempervirens presenta efecto insecticida fumigante sobre A. obtectus, y Tribolium castaneum (Herbst) (Tenebrionidae).…”

“…Bittner et al (2008) y Betancur et al (2010) describieron el efecto insecticida de contacto y fumigante además de actividad repelente del aceite esencial de P. boldus contra S. zeamais y Acanthoscelides obtectus (Say) (Bruchidae). Bittner et al (2008) y Zapata y Smagghe (2010), encontraron que el aceite esencial de L. sempervirens presenta efecto insecticida fumigante sobre A. obtectus, y Tribolium castaneum (Herbst) (Tenebrionidae). En relación a la acción tóxica de L. philippiana, Ortiz et al (2012) indicaron que el polvo de hojas secas de esta planta tiene toxicidad por contacto y causa repelencia hacia S. zeamais.…”