USE OF Cymbopogon citratus EXTRACT AS A LARVICIDE IN THE CONTROL OF Aedes aegypti

Abstract

In Brazil, arboviral diseases such as dengue, chikungunya, and Zika all transmitted by the same vector, Aedes aegypti have become a major public health concern. A. aegypti is fully adapted to urban environments, which makes its eradication difficult. This study aimed to evaluate the larvicidal effect of plant extract from lemongrass (Cymbopogon citratus) on A. aegypti larvae. The research was conducted through experimental tests using lemongrass (C. citratus) plant extract and larvae of the mosquito A. aegypti. Mosquito eggs were collected using artificial traps known as ovitraps. For the bioassay, Eucatex paddles containing A. aegypti eggs were placed in trays with distilled water, where the eggs hatched and were maintained until third-instar larvae were obtained. The analyzed extract did not demonstrate effectiveness in causing larval mortality of A. aegypti. No toxicity was observed at the tested concentrations. However, at concentrations of 1,000 µg·mL⁻¹ and 500 µg·mL⁻¹, a cytotoxic tendency was observed, unlike the concentration of 250 µg·mL⁻¹. After 24 hours, pupae were found only at the concentration of 250 µg·mL⁻¹. The lemongrass extract at the concentrations tested in this study, according to standards reported in the literature, did not demonstrate toxicity toward A. aegypti larvae. Nevertheless, further studies are required to determine the minimum concentration of lemongrass extract capable of exhibiting toxic effects on A. aegypti larvae.