Molecular docking and chemical composition of commercial essential oils and their toxicity against Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae)

The market for plant essential oils (EOs) is expanding, and these products are commercialized for a wide range of purposes, including cosmetics, medicines, environmental aromatization, and phytotherapy. Terpenes and phenylpropanoids are present in the composition of EOs and are recognized for their ovicidal and larvicidal activities. Here, we determined the composition of six commercial EOs and verified if they had ovicidal and larvicidal activity against eggs and young larvae of Spodoptera frugiperda, a worldwide important insect pest. The six EOs had at least 96.66% of their constituents identified, with major compounds representing from 38.63% to 84.39% of the composition. In the egg bioassay, 78% of S. frugiperda eggs exposed to EOs became unviable, while neem oil made 42% of the eggs unviable. In general, the EOs’ efficiency decreased as the larvae aged, and Copaiba essential oil showed larvicidal activity comparable to neem oil, specifically against second-instar larvae among the tested EOs, with LC50 and LC95 values of 0.57% and 3.44% (v/v), respectively, against first-instar larvae, demonstrating the potential for insect pest control. To support the biological findings at the molecular level, in silico molecular docking simulations were performed using the crystal structure of the S. frugiperda Scavenger Receptor-C MAM domain (PDB ID: 8YT7). Thus, the results highlight the stage-dependent ovicidal and larvicidal potential of commercial essential oils against S. frugiperda, supporting their evaluation as botanical alternatives for pest management.