Bioassay and efficacy of clove flower stalk extract of Afo variety as a natural larvicidal

Abstract

This study aims to test the larvicidal bioassay of clove stalk extract against Aedes aegypti on a laboratory scale and field scale efficacy test in a bath. Samples of sun-dried clove flower stalks were made into water extracts and coarse powder measuring 8-10 mesh for efficacy tests in the bath. The experimental method with a completely randomized design model was used to test the effectiveness of the larvicide, which consisted of two stages: The aqueous extract was tested against Ae. aegypti third instar larvae for three concentrations, namely 10%, 20%, and 30%, plus control treatment with three repetitions; observations were made at 30 minutes and 60 minutes after application to see the number of dead larvae as stage one. The second stage was the efficacy test in the bath which was carried out by inserting clove coarse powder in packs of 20 grams, 30 grams, and 40 grams, as well as the control treatment with five replicates, observed every day to see the time of emergence of mosquito larvae in a matter of days. The results of the first stage test showed an effect of the concentration of clove flower stalk extract on the mortality rate of the larvae, which was indicated by a positive relationship, where the mortality rate of the larvae reached 100% at 60 minutes after application. In comparison, the second stage test showed that there was an effect of clove flower stalk coarse powder on the time of larvae emergence, where the average time for larvae emergence was up to 8.8 days in the treatment of 40 g of clove flower stalk coarse powder, 1.83 times longer than the control (4 .8 days). Clove flower stalk extract is effective as a larvicidal mosquito Ae. aegypti.