Abstract

Jianhua Lu* and Shuhui Wu

The essential oil was extracted by Soxhlet method with anhydrous diethyl ether from Ailanthus altissima Swingle (Sapindales: Simaroubaceae) bark, a traditional Chinese herbal plant and its repellent, contact and fumigant activities were investigated against four major stored grain insects. A. altissima bark oil significantly repelled Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), Oryzaephilus surinamensis (Linnaeus) (Coleoptera: Silvanidae), Sitophilus oryzae (Linnaeus) (Coleoptera: Curculionidae) and Liposcelis paeta Pearman (Psocoptera: Liposcelididae) adults, with the repellency value reaching IV grade or stronger during the whole exposure period. A. altissima bark oil also possessed strong contact toxicity on S. oryzae adults which gradually enhanced with increased exposure time and the corrected percentage mortality reached 76.5% after 72 h treatment. Furthermore, A. altissima bark oil had high fumigant activity against O. surinamensis and S. oryzae adults with the corrected percentage mortality 99.3 and 81.9% within 24 h, respectively.