Evaluación del proceso de obtención de insecticidas botánicos con la aplicación de secado y filtración para controlar Plutella xylostella en brócoli.

Abstract

Factors which influence in their effectiveness are unknown in the process of obtaining aqueous extracts used as botanical insecticides to control Plutella xylostella such as: drying time, pore size filtrations and concentration. In Ecuadorian Amazon, the research evaluated the variables through the drying process of 5 species of leaves as: Lonchocarpus nicou, Clibadium sp., Dieffenbachia costata, Xanthosoma purpuratum and Witheringia solanacea to 60°C. Aqueous extracts were also prepared in order to prove its efficiency applying mortality bioassays, anti-food effect and antiovipositor. It was obtained drying times of 21,07; 16,33; 11,55; 18,13 and 4,45 hours for leaves of L. nicou, Clibadium sp., D. costata, X. purpuratum and W. solanacea respectively. The pore size influences only in the pest on mortality with an extract of X. purpuratum. It is evident the anti-food effect at concentrations of 0,016 g/cc to extract of L. nicou; 0,08 to 0,01 g/cc to Clibadium sp.; 0,08 g/cc to D. costata; from 0,11 to 0,014 g/cc to X. purpuratum and 0,12 g/cc to W. solanacea. Finally, it is highlighted the ovipositors repellency with effective concentrations of 0,13 and 0,065 g/cc to L. nicou extract; 0,04 g/cc in D. costata; 0,11 g/cc in X. purpuratum; 0,012 and 0,06 g/cc W. solanacea. It is concluded that each studied specie had a specific drying time to achieve humidity from 2 and 2,5%bs, the pore size influences only in Xanthosoma purpuratum mortality and the effective concentrations vary according to the assessed effect. It is recommended to study bioactive compounds in extracts of 5 species.