Larvicidal Activities of Essential Oils Extracted from Five Algerian Medicinal Plants against Culiseta longiareolata Macquart. Larvae (Diptera: Culicidae)

Abstract

Objective: The use of essential oils in mosquito control is considered as a potential alternative of synthetic insecticides. Thecurrent study aimed to assess the larvicidal activity of the essential oils extracted from five medicinal plants collected fromnortheastern Algeria against the Culiseta longiareolata larvae, a vector of the Plasmodium species in birds and one of the mostabundant mosquito species in Algeria.Materials and Methods: The essential oils extracted from: Thymus vulgaris, Artemisia herba-alba, Juniperus phoenicea,Rosmarinus officinalis, and Eucalyptus globulus were tested against the 3rd and 4th instar Culiseta longiareolata larvae. Thelarvae were exposed to a series of concentrations of the tested essential oils for 24h. The concentrations that caused between10% and 90% mortality were replicated four times, and the entire test was repeated three times. The collected data were usedto determine the LC50 and LC90 values,Results: The tested oils revealed an efficient larvicidal activity. T. vulgaris showed 100% mortality at 80ppm final concentration,while the other tested oils showed 100% mortality at 200ppm. Furthermore, the lethal concentrations that caused 50% and90% mortality (LC50 and LC90) were varying. T. vulgaris was the most efficient essential oil (LC50=25.64ppm, LC90=50.53ppm),followed by J. Phoenicea (LC50=59.83ppm, LC90=137.68ppm), R. officinalis (LC50= 64.18ppm, LC90= 96.55ppm), A. herba-alba(LC50=86.67ppm, LC90=139.55ppm), then E. globules (LC50=95.83ppm, LC90= 168.25ppm).Conclusion: The use of essential oils or their principal active components as α-pinene, 1,8-cineole and Camphor may serveas an eco-friendly method to control mosquito larvae. Nevertheless, the field application of essential oils and their principalcomponents remains a fundamental step to evaluate the field efficacy of these botanic extracts and to note their possiblesecondary effects on non-targeted organisms.