Effects of Essential Oils on Biological Characteristics and Potential Molecular Targets in Spodoptera frugiperda

Abstract

<i>Spodoptera frugiperda</i> control methods have proved to be inefficient, which justifies the search for new control measures. In this search for botanical insecticides for controlling <i>S. frugiperda</i>, the following were evaluated: (i) the toxicity of essential oils (EOs) from <i>Cinnamodendron dinisii</i>, <i>Eugenia uniflora</i>, and <i>Melaleuca armillaris</i>; (ii) the effect of EOs on life table parameters against <i>S. frugiperda</i>; (iii) the chemical characterization of EOs; and (iv) the in silico interaction of the chemical constituents present in the three EOs with the molecular targets of <i>S. frugiperda</i>. The EO from <i>E. uniflora</i> had the lowest LD₅₀ (1.19 µg of EO/caterpillar). The major compounds bicyclogermacrene (18.64%) in <i>C. dinisii</i> and terpinolene (57.75%) in <i>M. armillaris</i> are highly predicted to interact with the octopamine receptor (OctpR). The compound 1,8-cineole (21.81%) in <i>M. armillaris</i> interacts mainly with a tolerant methoprene receptor (MET) and curzerene (41.22%) in <i>E. uniflora</i>, which acts on the OctpR receptor. Minor compounds, such as nerolidol in <i>C. dinisii</i> and β-elemene in <i>E. uniflora</i>, are highly ranked for multiple targets: AChE, MET, OctpR, and 5-HT1. It was concluded that the EO from <i>E. uniflora</i> negatively affects several biological parameters of <i>S. frugiperda</i> development and is promising as an active ingredient in formulations for controlling this insect pest.