Insecticidal and repellent activities of essential oils from Aloysia citriodora and Minthostachys verticillata against Sitophilus zeamais (Coleoptera: Curculionidae)

HERRERA J M; PESCHIUTTA, M. L.; DEFAGÓ, M. T.; CALVIMONTE, H.; ZYGADLO J. A.; ARECO, V. A.; ARENA, J. S.

La Falda

Jornada; XXI Jornadas Científicas SOCIEDAD DE BIOLOGÍA DE CÓRDOBA; 2017

The maize weevil Sitophilus zeamais Motschulsky is a worldwide primary pest of stored maize. Essential oils (EO) constitute an important source of natural bioactive compounds and are considered interesting alternatives to conventional insecticides against stored-product pests. The aim of the current study was to evaluate the insecticidal and repellent activities of EO from lemon verbena (Aloysia citriodora Palau) and peperina (Minthostachys verticillata Griseb. Epling) and of their combination, against S. zeamais. The insecticidal effect was evaluated through fumigant assays. Minthostachys verticillata EO showed the strongest fumigant activity (LC50=28.2 μL/L) followed by the combination of A. citriodora and M. verticillata EO, (CL50=77.6 μL/L), while A. citriodora EO was not toxic at 600 μL/L. The repellent effect was evaluated using a two-choice olfactometer. The EO of A. citriodora and M. verticillata had repellent activity against the maize weevil; however, the combination of both EO had a higher effect suggesting a possible synergism between EO components. The EO studied, alone or in combination, had interesting insecticidal and/or repellent properties and could be suggested for use in management plans against S. zeamais.