AZRA PARVEEN AND ARCHANA GAUR

The development of resistance by malaria parasite to conventional drugs poses a threat to malaria control. Hence there is a need to find new, effective, and ecofriendly remedies for malaria, including those derived from plants. Herbal products have been used traditionally by humans in many parts of the world. In the present study leaves and flowers of Catharanthus roseus Linn. were evaluated for larvicidal activity against Anopheles stephensi (L.). The larval mortality was observed after 24 and 48 hrs of time exposure. Both plant extracts showed significant larvicidal activity against Anopheles stephensi mosquito larvae. Catharanthus roseus Linn. flowers extract was found to be more effective mosquito larvicide, which was manifested by the highest percentage mortality on the larvae after 24 and 48 hours as compared to Catharanthus roseus Linn. leaves extract. LC50 value was calculated against different concentrations. It was recorded that lowest LC50 value was observed in the Catharanthus roseus Linn. flowers followed by leaves i.e. 72.10mg/l and 87.16 mg/l respectively after 24 h of exposure time and 41.02mg/l, and 62.05mg/l. respectively at 48 h of exposure time. The present study indicates that the larvicidal activities of the plants differ according to the plant species and plant parts used, which is supported by the presence of several bioactive chemicals. Further Catharanthus roseus Linn. plant extracts are effective mosquito vector control agents and deserves further investigation and may be useful for further integrated pest management programme.