Repellency and toxicity of essential oils from the leaves and bark of Laurelia sempervirens and Drimys winteri against Tribolium castaneum

摘要: Abstract We report here on the repellent activity, as well contact and fumigant toxicity, of four essential oils extracted from leaves bark Laurelia sempervirens Drimys winteri against an important stored-product insect pest: red flour beetle, Tribolium castaneum . The tested had a very strong activity towards T. when in filter paper arena test. After 4 h exposure >90% repellency was achieved with L. at low concentrations 0.032 μl/cm 2 , while for D. 3–10 times higher were needed to achieve this activity. Oils both, found be toxic applied topically or by fumigation. LD 50 values topical application 39 44 μg/mg insect; these 75 85 μg/mg insect. By fumigation, LC 1.6–1.7 μl/l air, 9.0–10.5 μl/l air oils. In addition, 50% beetles killed 100 LT 6.1–7.4 h. results obtained are discussed relation main constituents oil extracts. conclusion, may explored potential natural insecticide pests because their high insecticidal activities.