Abstract: To find some eco-friendly components from plants as mosquitocide, the fumigant activity of essential oil from Zanthoxylum ailanthoides fructification to the adults of Aedes albopictus and Culex pipiens quinquefasciatus was tested, and its insecticidal activity against the larvae and pupae of the two mosquito species was evaluated. The volatile components of this oil were also analyzed by gas chromatography-mass spectrometry. The results showed that at the dosage of 102.145 μg·cm^-3, the KT₅₀ values of this oil for adults of Ae. albopictus and Cx. pipiens quinquefasciatus were 2.788 and 3.505 min, respectively, while the 24 h mortalities of adults of the two mosquito species were 100% and 97.53%, respectively. The 24 h LC₅₀ values of this oil for 4th instar larvae of Ae. albopictus and Cx. pipiens quinquefasciatus were 45.237 and 20.759 mg·L^-1, respectively. Fourteen chemical compounds were identified from the essential oil from Z.ailanthoides fructification, and the main component of this essential oil is 2-undecanone with the peak-area ratio of 89.86%. The results demonstrate that the oil from Z. ailanthoides fructification has strong insecticidal activity against A. albopictus and Cx. pipiens quinquefasciatus, and it has a great potential to be developed as a natural mosquitocide.

Key words: Zanthoxylum ailanthoides, essential oil, insecticidal activity, Aedes albopictus, Culex pipiens quinquefasciatus, active ingredients