Larvicidal effect of Prosopis juliflora on Aedes aegypti (Diptera: Culicidae)

Abstract

The aim of this work was to evaluate the larvicidal effect of aqueous extracts of Prosopis juliflora on A. aegypti. Oviposition traps (ovitramps) were used to obtain the insect's eggs. The test was carried out at the Agricultural Entomology Laboratory of the Federal University of Cariri, Crato, Ceará, Brazil, with controlled temperature, humidity and photophase, using larvae in the 3º instar. The design used was completely randomized (DIC) with five doses (10, 20, 30, 40 and 50 g L-1) of the aqueous extract plus two control treatments (pyriproxifene at 0.01g L-1 and distilled water). The treatments were evaluated after 24, 48, 72, 96, 120, 144 and 168 h of exposure of the larvae, being considered dead those that did not react to the mechanical stimulus of a clamp. The doses of 40 and 50 g L-1 of P. juliflora are effective in the mortality of A. aegypti larvae after 48 h of exposure, with greater efficiency (100% mortality) after 120 h. The lowest doses (10 and 20 g L-1) have low mortality efficiency, while the dose of 30 g L-1 causes satisfactory mortality after 148 h of exposure. The aqueous extract of the leaves of P. Juliflora (in doses of 40 and 50 g L-1) is effective in controlling A. aegypti.