Repellent activities of ethanolic extract of Cymbopogon citratus (Poaceae) and Ocimum basilicum L. (Lamiaceae) leaves against Aedes aegypti mosquitoes in Dogbo district in south-western Benin, West Africa

The use of chemical insecticides causes important damages to environment and human health and there is a need to search for alternative solutions. The current study was aimed to evaluate the repellent activities of ethanolic extract of Cymbopogon citratus (Poaceae) and Ocimum basilicum L. (Lamiaceae) leaves against Aedes aegypti adult mosquitoes in dengue vector control in Dogbo district in south-western Republic of Benin. Larvae of Aedes aegypti mosquitoes were collected from breeding sites using the dipping method from September to November 2023 during the small rainy season in Dogbo district of Couffo department. Then, these larvae were reared in insectary until became adult mosquitoes. Repellent activities of ethanolic extract of both plant leaves were measured on adult mosquitoes with different concentrations of 1mg/cm2, 2mg/cm2, 3mg/cm2, 4mg/cm2 and 5mg/cm2. The results showed that the leaves of both plants had repellent effects against Aedes aegypti adult mosquitoes. However, the repellent activity of Cymbopogon citratus was higher than that of Ocimum basilicum L. Both ethanolic extracts of Cymbopogon citratus and Ocimum basilicum L leaves are found to be effective in the repellency against the bites of Aedes aegypti adult mosquitoes.