In-vitro study on the larvicidal activity of Manihot glaziovii peel extract against Aedes aegypti larvae

Abstract

Use of chemical method to control Aedes aegypti population in the Dengue endemic areas caused the emergence of a resistant strain of this species to insecticide compounds, including temephos. Exploration of the alternative compounds that have larvicidal effects is needed, such as natural products derivate from plants. The current study was designed to evaluate the effective dosage of methanolic extract of Manihot glaziovii peel against the third instar larvae of Aedes aegypti. Bioassay test was performed based on the WHO procedure to occupy the 24 hours exposure of five levels dosages of Manihot glaziovii peel extract, namely 1,800, 2,400, 3,000, 3,600 and 4,200 ppm respectively. As many as 25 of healthy Aedes aegypti larvae were subjected into each group, five-time replicated and compared with tap water control group. The mortality rate of Aedes aegypti larvae has increased due to the increase in treatment groups dosages, ranged from 44–97.6%. It is significantly different in larvae mortality rate between different treatment groups. There was no observation of killed larvae in the control group. LD50 and LD90 of methanolic extract of Manihot glaziovii peel were measured 2,027 ppm and 3,772 ppm, respectively. This result suggests the possible use as an ecofriendly larvicide against Aedes aegypti larvae. Further investigation is needed to obtain secondary metabolites of this plant.