Mosquito larvicidal and biting deterrency activity of bud of Polianthes tuberosa plants extract against Anopheles stephensi and Culex quinquefasciatus.

Mosquito control by phytochemicals is an alternative method to synthetic insecticides, as it is biodegradable and non resistant to vector mosquito. Polianthes tuberosa is a perennial plant distributed in many parts of India. The present study was undertaken to scientifically evaluate the larvicide and biting deterrency activity of bud of Polianthes tuberosa against Culex quinquefasciatus and Anopheles stephensi. Crude and solvent extract [ethyl acetate, chloroform: methanol (1:1, v/v), acetone] of fresh, mature, bud of P. tuberosa was tested against (ex. quinquefasciatus and An. stephensi. The repellent activity tested by chloroform: methanol (1:1, v/v) solvent extract against both mosquito species. The appropriate lethal concentrations at 24h for chloroform: methanol (1:1, v/v) extract was also studied on non target organisms such as Toxorhynchites larvae, Diplonychus annulatum and Chironomus circumdatus. In a 72 hour bioassay experiment, 0.5% crude extract showed the highest mortality and chloroform: methanol (1:1, v/v) solvent extract showed the highest mortality, the maximum (p < 0.05) mortality was recorded at a concentration of 60 ppm. The chloroform: methanol (1:1, v/v) solvent extract provide 4h protection against Cx. quinquefasciatus and 5h against An. stephensi from biting. Both crude and chloroform: methanol (1:1, v/v) extract showed good result against Cx. quinquefasciatus, so it could be used as a mosquito larvicide agent. There is no changes in the activity non-target organism so, it is safe to use.