Chemical Composition and Acaricidal and Insecticidal Activity of the Essential Oil of Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae).

Abstract

Tithonia diversifolia is a plant from the Asteraceae family that, due to the large quantity of hydrogenated monoterpenes present in its essential oil, can be used to prepare a product capable of combating agricultural pests. Therefore, the aim of this study was to carry out a phytochemical screening of the components of the essential oil produced by hydrodistillation of the leaves of T. diversifolia and to verify its possible acaricidal applications in the control of the Tetranychus urticae (Koch, 1836) (Acari: Tetranychidae) and insecticidal applications in the control of the de Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae), both via fumigation. Gas chromatography coupled with mass spectrometry revealed the presence of 32.67% β-pinene, 24.74% α-pinene and 22.69% limonene, among other components, in the essential oil of T. diversifolia. Fumigation tests revealed 52% mortality of T. urticae at a concentration of 20 µL/L of air and 96% at 80 µL/L of air. The insecticidal activity tests on the S. zeamais showed no mortality, but the repellency tests on this same insect showed promising results close to 100% at a concentration of 10 µL/L of air. Taken together, these results confirm the acaricidal efficacy of the essential oil through fumigation against the T. urticae and its repellent activity against the S. zeamais. These results suggest the potential for further research into the application of the chemical components of T. diversifolia essential oil in arthropod control.