Insect growth regulatory activity of Acalypha alnifolia (Euphorbiaceae) and Vitex negundo (Verbenaceae) leaf extracts against Aedes aegypti (Diptera: Culicidae)

摘要

The methanolic leaf extracts of Acalypha alnifolia and Vitex negundo were studied for IGRs activityagainst Aedes aegypti. The developmental bioassay using standard WHO protocol was tested for larval,pupal and adult development activity against freshly emerged first instar larvae of A. aegypti followed bythe standard procedure. Effect of A. alnifolia showed (L1 to L4) prolonged larval duration and up to 8days at 500 ppm. Whereas, control was reached up to 4 day of complete larval development. Effect of A.alnifolia showed (L1 to L4) prolonged larval duration and up to 8 days at 500 ppm. Whereas, in controlcomplete larval development was completed in 4 days. Similarly, methonolic extract of V. negundo wasprolonged larval (L1 to L4) duration up to 3 to 5 days at 500 ppm concentration than the control.Combined treatment of both extracts showed higher significant prolongation of larval, pupal and adultduration and was reached up to 7 days. The adult emergence period was extended to 28 days, whereas, incontrol it was reached to 12 days. Hence, the present study clearly showed that larval, pupal and adultemergence was greatly inhibited by the present active compound in the plants.