Toxicity of various essential oils and their volatile constituents towards the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in essential oil from eucalyptus (LD50 = 28.9 μl/l air). GC-MS analysis of essential oil from eucalyptus showed it to be rich in 1,8-cineole (81.1%), limonene (7.6%) and α-pinene (4.0%). Treatment of S. oryzae with each of these terpenes showed 1,8-cineole to be most active (LD50=23.5 μl/l air). In addition to 1,8-cineole, benzaldehyde (LD50 = 8.65 μl/l air) occurring in peach and almond kernels had a potent fumigant toxicity towards the rice weevils. Therefore, benzaldehyde and other natural volatiles could be a safer fumigant to control stored-grain insect pests than those currently used. © 2001 Elsevier Science Ltd.
Lee, B. H., Choi, W. S., Lee, S. E., & Park, B. S. (2001). Fumigant toxicity of essential oils and their constituent compounds towards the rice weevil, Sitophilus oryzae (L.). Crop Protection, 20(4), 317–320. https://doi.org/10.1016/S0261-2194(00)00158-7