The efficacy of piper aduncum extract as natural larvicides against aedes aegypti larvae

Abstract

Many studies showed that Piper aduncum had low toxicity towards the environment. The aim of this study is to investigate the efficacy of P. aduncum on the Aedes aegypti larvae's morphology. P. aduncum were extracted using n-Hexane, dichloromethane and ethanol and dilutions were made for larvicidal bioassays at concentrations of 50 mg/ml, 25 mg/ml and 12.5 mg/ml. Commercial larvicide, Bti was used as a positive control. The mortality and motility test of A. aegypti larvae was recorded after exposed to different concentrations for 24 hours. The morphology of treated A. aegypti larvae was observed under inverted microscope. All concentrations showed 100% of mortality after 24 hours of treatment. Although the commercial larvicide, Bti showed its effectiveness against A. aegypti larvae, it was found that the 50 mg/ml ethanol extract of P. aduncum leaves was the most potent as larvicidal with the higher knockdown effect in less than 10 minutes exposure. The morphology showed the larvae darken in colour with shrunken, torn anal papillae and siphon, segmented body, loss of brushes and antenna. These results indicate that P. aduncum extracts has potential to be used as alternative control agents for A. aegypti.