CHEMICAL COMPOSITION AND ACARICIDAL EFFECT OF THE Eugenia uniflora ESSENTIAL OIL AGAINST TWO Tetranychus (Acari: Tetranychiade) SPECIES

Abstract

Tetranychus evansi Baker & Pritchard and Tetranychus urticae Koch (Acari: Tetranychiade) are important mites for the economy of many countries. Populations from these species have presented resistance to acaricides of different chemical groups, thus demanding new products with an acaricidal effect. Essential oils have been investigated. The chemical composition and acaricidal effect of the Eugenia uniflora L. (Myrtaceae) essential oil were investigated. The essential oil was extracted by hydro-distillation and the chemical composition was identified by Gas Chromatography coupled to Mass Spectrometry (GC/MS). Repellence, fumigation and residual effect tests were performed. The essential oil presented the sesquiterpenes selin-1,3,7(11)-trien-8-one and selin-1,3,7(11)-trien-8-one epoxide. Repellence occurred against T. urticae and T. evansi. Oil vapors provoked 100% T. evansi mortality at all concentrations and time intervals tested with significant mortalities being observed against T. urticae after 48 h. Tetranychus evansi mortalities greater than 80% due to a residual effect were recorded after 24 h, whereas no significant mortality was observed for T. urticae.