Chemical Composition and Larvicidal Activity of Essential Oils from Different Mentha L. and Pulegium Species against Culex quinquefasciatus Say (Diptera: Culicidae)

Twenty samples of essential oils (EO) obtained from Mentha aquatica, M. longifolia, M. spicata, M. suaveolens, M. x piperita, M. x piperita var. crispa, M. x villosa, and Pulegium vulgare were tested for larvicidal activity against Culex quinquefasciatus. EO were obtained via hydrodistillation and subsequently analysed by gas chromatography-mass spectrometry (GC-MS). Concentrations causing 50% or 90% larval mortality ranged from 17171 mg/l to 171 mg/l or 28171 mg/l to 577 mg/l, respectively. EO obtained from M. longifolia 2 and M. suaveolens, which were the only ones containing a majority share of piperitenone oxide, showed the highest effects. LD50 was estimated as 17 mg/l for both EO, and LD90 was estimated as 28 mg/l.