ACTIVITY OF PLANT DERIVED PRODUCTS IN THE WHITEFLY (Bemisia tabaci) AND ITS PARASITOID Encarsia Formosa

Abstract

The goal of this research was to evaluate the activity of aqueous extracts of regional plants and commercial botanical insecticides on the whitefly (Bemisia tabaci) and its parasitoid (Encarsia formosa). The evaluations of adult repellence (IR) and oviposition deterrence (IDO) were carried out in entomological cages for 48 hours period, whereas the evaluation of suppression of whitefly population density on plants under greenhouse conditions was carried out through the application of treatments for one moth at week intervals. In the first assay all aqueous extracts of regional plants and commercial botanical insecticides were evaluated, whereas in the second assay only treatments with consistent effects on IR and IDO were evaluated. Evaluations in entomological cages showed that plants tretated with the aqueous extracts of Croton itzaeus (stem and leaf) and the botanical insecticides derived from Azadirachta indica and Argemone mexicana, produced high adult repellency and high oviposition deterrence. In greehouse trails, plants treated with aqueous extracts of Erythroxylum confusum (stem) had low population density of adults and nymphs. Plants treated with the botanical insecticides derived from Allium-Capsicum-Cinnamomum had significantly lower population density of adults, but not of nymphs or eggs. The botanical insecticides derived from A. indica and A. mexicana caused high mortality on the parasitoid E. formosa.