Mosquito repellent activity of Piper betel Linn.

Essential oil of Piper betel provided better protection from biting of mosquitoes Anopheles stephensi and Culex fatigans compared to known mosquito repellent citronella oil. Piper betel oil provided more than 4 hrs protection against Anopheles stephensi and Culex fatigans when applied at the rate of 20μl/cm2 where as citronella oil provided only 2.2 and 2.6 hrs protection respectively. Piper betel oil showed more fumigant action than that of citronella oil, LC50 (30 min) was 24.81 and 20. 51 μl/liter air against Anopheles stephensi and Culex fatigans where as LC50 of citronella oil was 32.71 and 31.97 μl/liter air, respectively.