Larvicidal and Repellent Potential of Chenopodium ambrosioides Linn Essential Oil against Anopheles gambiae Giles (Diptera: Culicidae)

Larvicidal and repellent effect of the essential oil from the seeds and leaves of Chenopodium ambrosioides Linn were evaluated against the larvae and adults of Anopheles gambiae s.s. mosquitoes at concentrations of 0, 50, 75, 100, 200, 300 and 400 ppm. Total mortality of larvae occurred at 200ppm and 300ppm for the essential oils from seeds and leaves respectively. Alpha-terpinene (73.55% for the seeds; 40.69% for the leaves) and para-cymene (20.05% for the seeds; 45.44% for the leaves) are the principal constituents. There was a 100% repellent effect on adult mosquitoes at 200ppm, with protection time of at least four hours for both seed and leaf essential oils. The findings indicated that C. ambrosioides Linn possess mosquito larvicidal and repellent potentials that might be further exploited in combating ma- laria through anti-vector intervention.