Essential oils (EOs) are volatile products derived from the secondary metabolism of plants with antioxidant, antimicrobial, and pesticidal properties. They have traditionally been used in medicine, cosmetics, and food additives. In agriculture, EOs stand out as natural alternatives for pest control, as they show biocidal, repellent, and antifeedant effects. However, they are highly volatile compounds and susceptible to oxidation, which has limited their use as pesticides. This has led to exploring micro- and nano-scale encapsulation to protect these compounds, improving their stability and allowing for a controlled release. Various encapsulation techniques exist, such as emulsification, ionic gelation, and complex coacervation. Nanoemulsions are useful in the food industry, while ionic gelation and complex coacervation offer high encapsulation efficiency. Materials such as chitosan, gelatin-gum-Arabic, and cyclodextrins are promising for agricultural applications, providing stability and the controlled release of EOs. Encapsulation technology is still under development but offers sustainable alternatives to conventional agrochemicals. This article reviews the potential of EOs in pest management and encapsulation techniques that enhance their efficacy.

Pest control is a main concern in agriculture. Indiscriminate application of synthetic pesticides has caused negative impacts leading to the rapid development of resistance in arthropod pests. Plant secondary metabolites have been proposed as a safer alternative to conventional pesticides. Monoterpenoids have reported bioactivities against important pests; however, due to their high volatility, low water solubility and chemical instability, the application of these compounds has been limited. Nanosystems represent a potential vehicle for the broad application of monoterpenoids. In this study, an 1,8-cineole nanoemulsion was prepared by the low energy method of phase inversion, characterization of droplet size distribution and polydispersity index (PDI) was carried out by dynamic light scattering and stability was evaluated by centrifugation and Turbiscan analysis. Fumigant bioactivity was evaluated against Tetranychus urticae, Rhopalosiphum maidis and Bemisia tabaci. A nanoemulsion with oil:surfactant:water ratio of 0.5:1:8.5 had a droplet size of 14.7 nm and PDI of 0.178. Formulation was stable after centrifugation and the Turbiscan analysis showed no particle migration and a delta backscattering of ±1%. Nanoemulsion exhibited around 50% more bioactivity as a fumigant on arthropods when compared to free monoterpenoid. These results suggest that nanoformulations can provide volatile compounds of protection against volatilization, improving their bioactivity.