Bioactivity of essential oils to Bemisia tabaci MED (biotype q) (Hemiptera: Aleyrodidae) on tomato

Abstract

Tomato Solanum lycopersicon L. (Solanaceae) has a great economic importance in Brazil, with the high in natura production and consumption as well as industrial processing. Whitefly species of Bemisia tabaci complex (Hemiptera: Aleyrodidae) are key tomato pests due to direct and indirect damage, which reduces crop yield. In Brazil, B. tabaci Mediterranean (MED) was first identified in 2014 in Rio Grande do Sul, and subsequently spread throughout the country. B. tabaci MED may be a potential pest for tomato crop considering its recognition for lower susceptibility to insecticides, greater competitive ability over Middle East-Asia Minor 1 (MEAM1) species and higher virus transmission eciency. Therefore, the development of efficient and more sustainable control methods for B. tabaci MED is necessary. In this sense, the use of essential oils for pest control have been promising because they are natural chemicals (non synthetic) with great diversity of interacting compounds, which implies a lower selection pressure and delay in the emergence of resistant insect populations. Thus, this project aims to evaluate the essential oils of Pelargonium graveolens L'Her. (Geraniaceae), Eugenia uniflora L. (Myrtaceae), and Piper callosum Ruiz & Pav. (Piperaceae) bioactivity on B. tabaci MED. Lethal concentration (LC's) curves of essential oils and major compounds will be estimated for whitefly nymphs. Thereafter, LC50 and LC90 determined for nymphs will be used to assess egg and adult mortality. A semi-field bioassay will be performed using the most promising essential oil. Therefore, the essential oils are expected to be efficient in controlling B. tabaci MED and that can be incorporated as a valuable strategy for alternative tomato insect management.