Evaluation of mosquitocidal activities of Lepidium sativum L. and Millettia ferruginea (Hochst) Baker essential oils against the malaria vector, Anopheles gambiae sensu lato (Diptera: Culicidae)

Abstract

Anopheles gambiae sensu lato is one of the important mosquito species transmitting Plasmodium falciparum in several parts of Ethiopia. In order to find out eco-friendly vector control sources, the present study was initiated to isolate essential oils from Lepidium sativum, Millettia ferruginea and their bio-potential against immature and adult Anopheles gambiae. This plant was indigenous to Ethiopia and traditionally used by local people to control pest and vectors. The mosquitocidal properties of the essential oils were tested following World Health Organization (WHO) recommended a protocol. After 72 hr exposure period, 96.00 and 100.00% IInd instar larva mortality was observed at 100 ppm concentration of L. sativum and M. ferruginea respectively. In IVth instar larva, 91.00 and 96.00% mortality was recorded at 100 ppm concentration of L. sativum and M. ferruginea respectively after 72 hr. The pupal mortality was 99 and 100% in L. sativum and M. ferrugiena essential oil respectively at 100 ppm concentration after 72 hr. After 1 hr exposure period, median knockdown time of 7.34 minute was recorded at 10% concentration of M. ferruginea essential oil impregnated filter paper. The percentage of adult mortality was 95.66% and 82.66% exposed to 10% concentration of M. ferruginea and L. sativum essential oil respectively. Results clearly demonstrate the strong mosquitocidal potential of L. sativum and M. ferruginea essential oils against An. gambiae. However, further formulation and field evaluation are important for large scale field application to control the population of An. gambiae.