Composition, toxicity and developmental potential of three essential oils on the West Nile virus mosquito, Culex pipiens L

Abstract

The toxic and developmental properties of the three essential oils isolated from Artemisia monosperma, Origanum vulgare and Schinus molle were evaluated against Culex pipiens. Gas chromatography/mass spectrometry (GC/MS) analysis showed that capillene (36.86%), d-pulegone (77.45%) and α-phellandrene (29.78%) were the most dominant compounds in A. monosperma, O. vulgare and S. molle, respectively. The toxicity of the oils was evaluated against larvae, pupae and adults of C. pipiens after treatments of the 1st instar mosquito larvae with different concentrations of oils. The oils of O. vulgare, A. monosperma and S. molle caused 77.33, 64.0 and 56.67% larval mortality at 100 mg/L, respectively. The oils showed a strong cumulative toxicity with LC50 values of 10.27, 12.75 and 14.52 mg/L for O. vulgare, S. molle and A. monosperma, respectively. Moreover, the oil of O. vulgare strongly inhibited adult eclosion with IC50 value of 10.50 mg/L. Furthermore, the oils caused significant prolongation of the larval and pupal periods. In contrary, the oils drastically shortened adult periods of C. pipiens. Moreover, the three oils induced pupal and adult malformation.