EVALUANTION OF COMMERCIAL PROCUCT NIM CITROMAX® IN THE CONTROL OF Plutella xylostella L. IN LABORATORY

Abstract

The cruciferous moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a pest of worldwide importance and with great appeal for studies aiming at its control. The objective of this work was to evaluate the insecticide potential of the commercial Nim Citromax® product (neem based) at different concentrations (10; 5; 2.5; 1.25 and 0.625 and 0%) diluted in distilled water plus Tween 80 (0.1%). The rearing and multiplication of P. xylostella was carried out under 25 ± 2 °C, 67 ± 2% relative humidity and 12h photophase conditions. Leaf disks of 8 cm diameter were made with cabbage leaves and sprayed with the product using Potter tower. The application was performed at a pressure of 5 psi / in² using a 2.3 mL spray volume, which corresponds to a deposit of 1.6 ± 0.37 mg/cm². Three days after the experiments were set up, the mortality of the caterpillars was evaluated. The experiment was organized in a completely randomized design with six treatments and five replications with 10 first instar caterpillars per plot. Data were subjected to analysis of variance and means compared by Tukey test performed in the statistical program ASSISTAT version 7.7 and regression analysis using the Excel program. each treatment having five repetitions consisting of 10 first instar caterpillars. Results showed that treatment averages differed at the 1% probability level with an F = 62.2296, with larval mortality averages reaching up to 96%. Mortality means increased linearly as product concentrations increased, showing an R = 0.96. It can be concluded that the application of the commercial product Nim Citromax® at a concentration of 10% presented higher mortality rate (96%) of P. xylostella.