Essential oils (EOs) have diverse chemical compositions depending on the
plant species used, but the most common constituents present in EOs are mono- and
sesquiterpenoids. Such volatile terpenoids have different functions in plant ecology,
acting, for example, as chemical defenses against fungi, bacteria, and insects, attracting
pollinators, inhibiting germination, and mediating intra- and interspecific plant
communication. Mainly terpenoids present the ability to inhibit the main families of
detoxifying enzymes of insects, allowing the formulation of botanical insecticides, and
using blends of EO compounds considered synergists among themselves. In this case,
both combinations of essential oils from different plants and the enrichment of essential
oils and/or their fractions with compounds with proven synergistic effects can be
considered. This chapter presents research results that indicate synergistic, additive,
and antagonistic interactions between terpenoids, indicating that this is one of the main
properties considered when formulating insecticides based on commercially available
EOs. Considerable advances are still necessary for large-scale production, and
limitations related to raw material supply, registration, and, mainly, adequacy of
formulations for the control of different targets without phytotoxic effects, are the main
challenges to be overcome in the short-term
Keywords: Additivism, Antagonism, Agrochemical Industry, Aromatic Plants, Bioinsecticides, Biological Interference, Botanical Insecticides, Cytochrome P450, Enzyme Inhibition, Esterases, Essential Oils, Glutathione S-Transferase, Insecticide Formulations, Integrated Pest Management, Insect Toxicology, Insecticidal Plants, Microsomal Monooxygenases, Pest Control, Synergism, Terpenoid Blends.
