Comparison of Fumigation Activities of 9 Kinds of Essential Oils against the Adults of Maize Weevil, Sitophilus zeamaise Motschulsky(Coleoptera:Curculionidae)

By means of sealing jar, fumigant toxicities of the essential oils of Citrus tangerina, Citrus limon, Citrus hongheensis, Litsea cubeba, Mentha spicata, Pinus tabulaeformis, Cinnamoum camphora, Melaleuca alternifolia and Eucalyptus globules on adults of maize weevil, Sitophilus zeamaise Motschulsky were investigated at the dosage of 16 μL/L and under the exposure times of 24 h, 36 h, 48 h, and 60 h, respectively. The results indicated that fumigation efficacies of the essential oils of Cinnamoum camphora, Melaleuca alternifolia, Citrus limon, Mentha spicata, and Pinus tabulaeformis are better than those of the other four essential oils, and Cinnamoum camphora oil showed the best fumigation toxicity. The LC50s of the maize weevil adults fumigated by Cinnamoum camphora oil under the exposure times of 12 h, 24 h, 36 h, 48 h and 60 h are 31.43,11.26,6.16,2.72 and 1.11 μL/L, respectively. Cinnamoum camphora oil can be considered as a promising alternative substance for methyl bromide and phosphine to control maize weevil.