Larvicidal activity of six Moroccan Artemisia essential oils and a correlation study of their major components against Culex pipiens

The present study was carried out for the first time in Morocco to valorise plant species of the Artemisia genus. Its aim was to evaluate the larvicidal activity of essential oils from six Artemisia plants (A. herba alba, A. absinthium, A. campestris L., A. negrei, A. pontica, and A. arborescens) against Culex pipiens mosquitoes, which are recognised as potential vectors of West Nile virus. Bioinsecticides derived from EOs have shown promise as effective mosquito control agents. The EOs were analysed using GC–MS and GC-FID and were obtained by hydrodistillation from the aerial parts of the plants. Besides, the experiment was carried out according to the standard WHO protocol. Thujone and camphor were identified as the predominant compounds in all six Artemisia plants. A. herba alba demonstrated the highest larvicidal activity with LC₅₀ and LC₉₀ values of 4.85 and 15.39 μg/mL, respectively. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were employed to explore the correlation between major EO compounds and larvicidal efficacy. The results suggest that these findings could pave the way for the development of tailored biocides that specifically target important disease vectors.