Aroma profile and fumigant toxicity of two Moroccan Lavandula species essential oils against Culex pipiens (Diptera: Culicidae)

In this study, Lavandula stoechas and Lavandula officinalis essential oils were evaluated for their adulticidal effect against Culex pipiens . The fumigant toxicity assay was carried out against female adults of Culex pipiens using a fumigant test in glass jars. The chemical composition analyses showed that the main volatile components in Lavandula stoechas essential oil were camphor, fenchone, camphene, borneol, and α-pinene. In contrast, Lavandula officinalis essential oil was dominated by linalool, 1,8 cineole, camphor, camphene, and α-pinene. Results revealed that Lavandula stoechas and Lavandula officinalis essential oils presented an insecticidal activity against female adults of Culex pipiens. Lavandula stoechas was the most effective with 68.42 ± 1.54% of mortality at 0.03125% after 48 h of treatment and the LD 50 value was determined at 83.99 µl/L air (R 2 = 0.93; P-value = 0.008). Our findings on plant-based essential oils could serve as preliminary data for elaborating new natural toxic products that might be used as a mosquitocidal tool in the integrated programs to control mosquito vectors and also to manage chemical insecticide resistance. Graphical abstract The fumigant test indicated that both essential oils obtained from Lavandula stoechas and Lavandula officinalis have an insecticidal effect against the female adults of Culex pipiens after 24 and 48 h of treatment.