Abstract

Objective: To evaluate the larvicide and biting deterrency activity of bud of Polianthes tuberosa (P. tuberosa) against Culex quinquefasciatus (Cx. quinquefasciatus) and Anopheles stephensi (An. stephensi). Methods: Crude and solvent extract [ethyl acetate, chloroform: methanol (1:1, v/v), acetone] of fresh, mature, bud of P. tuberosa was tested against Cx. 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 24 h for chloroform: methanol (1:1, v/v) extract was also studied on non target organisms such as Toxorhynchites larvae, Diplonychus annulatum and Chironomus circumdatus. Results: In a 72 h 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 mg/L. The chloroform: methanol (1:1, v/v) solvent extract provide 4 h protection against Cx. quinquefasciatus and 5 h against An. stephensi from biting. Conclusions: Both crude and chloroform: methanol (1:1, v/v) extract showed efficient activity against Cx. quinquefasciatus, so it could be used as a mosquito larvicide agent. There is no change in the activity of non-target organism so, it is safe to use.

Authors and Affiliations