Larvicidal activity of Artemisia annua L. callus culture against Anopheles stephensi larvae

The emergence of resistance by both Plasmodium falciparum and Anopheles stephensi made the search for an alternative environmentally safe plant based insecticide inevitable. Artemisia annua is a well known antimalarial. Present study is an attempt to induce callus production from young leaves of Artemisia annua plant and study its larvicidal activity against larvae of Anopheles stephensi. Callus was initiated by using different concentrations of auxins and cytokinins. A suitable culture media was standardized for optimal growth of callus. Healthy callus cultures were obtained in the slightly modified Murashige and Skoog's medium +NAA and BAP (0.03 and 0.2 mg l(-1) respectively) + Sucrose 20 gm l(-1) +Agar 8 gm l(-1) within 28 days of inoculation. Callus was successively extracted in order of increasing polarity of solvents. Larvicidal activity, in terms of lethal concentration (LC50) of the callus extract in chloroform was calculated to be 18.45 +/- 0.75 ppm after72 hr against third instar larvae of A. stephensi.