The aim of the study was to investigate the effect of Opuntia delleni leaves on Dengue Vector Aedes aegypti. Larvae on molecular DNA extraction. The plant Opuntia delleni Linn (Verbenaceae) is described in Ayurveda and Siddha as a potent drug for a variety of ailments. The plant was collected, authenticated and extracted using hexane, chloroform, ethylacetate and ethanol solvent. The phytochemical, physico chemical and TLC studies were done and further larvicidal activity was performed. The results of the chloroform extract of Opuntia delleni showed the presence of terpenoids, flavanoids and glycoside. TLC studies showed the results of 7 spots with Rf value range from 0.06-0.96 in the mobile phase Chloroform: Ethanol (7:3). Opuntia dellen is extracts showed potent larvicidal activity. The LC50 value for 24 hr observation was very high indicating potent activity. Among the extracts, methanol showed comparatively better activity. The LC50 value of chloroform was 6 lesser than other extract against A. Aegypti. The toxic effects resulting in the mortality manifested differently on exposure to the extracts at different times. However, more than 80% mortality was observed only at higher concentrations. The larvae was subjected for DNA isolation by standard procedure and run in Agarose Gel Electrophoresis and observed in UV light. The DNA fragment pattern was observed for chloroform extract of Opuntia Delleni which showed potent effect on Larvae Aedes aegypti. Thus the molecular studies on Dengue vector Larvae Aedes aegypti was potent with chloroform extract of Opuntia delleni leaves
