The whitefly Bemisia tuberculata (Bondar, 1923) (Hem.: Aleyrodidae) is the main pest of cassava crops in Mato Grosso do Sul state, however there are no products registered for its control. Plant products may represent a viable alternative for insect pest control and, due to their photo-degradability, they may reduce risks to the environment and to man. The aim of this study is to assess the effect of "cajuzinho-do-cerrado" Anacardium humile St Hill (Anacardeaceae) aqueous leaf extract on the biology of B. tuberculata at the concentrations 2.0; 0.8; 0.4; 0.05%, as well as to identify the class of secondary metabolites present in the referred extract. The experiment was carried out in a greenhouse at a temperature of 26±4°C. The aqueous extract of A. humile caused an increase in the duration of the larval phase and a significantly higher mortality rate than the control at all the tested concentration levels. It was concluded that the aqueous extract of A. humile leaves causes mortality in B. tuberculata nymphs and the prolongation of the nymph phase in surviving insects. The aqueous extract of A. humile leaves contains tannin, reducing sugars and saponins, and the foaming rate (Afrosymmetric Rate) is 1250.
Insecta; insecticidal plants; triterpenoids
