Botanical sources, mechanisms and efficacy of biopesticides derived from plant essential oils

The majority of the chemical pesticides used in crop farming can harm the environment and human health. As a result, the farming community and the general public are looking for safer and more natural ways to control pests. Plant essential oils (PEOs) from herbs, spices, and other plants are showing great promise as natural pesticides. This review synthesizes current knowledge on the mechanisms of action of PEOs, including neurotoxicity, membrane disruption, and enzymatic inhibition, highlighting their efficacy against a broad spectrum of insect pests, fungi, and weeds. Evidence from comparative trials indicates that, under optimized formulations and controlled experimental conditions, PEOs can achieve pest suppression rates approaching those of synthetic pesticides. However, reproducibility across different crops, environments, and application methods remains variable, underscoring the importance of contextualizing efficacy claims. By improving field stability and dose efficiency, advances in nano-encapsulation, emulsification, and controlled-release technologies have addressed issues with volatility and photodegradation. Notwithstanding their potential, standardization, scalability, and regulatory harmonization poses challenges to the broad use of PEOs. Chemotypic variability, inconsistent field performance, and limited farmer awareness constrain the market popularity of the PEOs. Nonetheless, their regulatory approaches are policy innovations like the Generally Recognized as Safe (GRAS) designation, basic substance approval, and incorporation into integrated pest management (IPM) frameworks. Long-term ecological assessments, sublethal toxicity studies, and omics-based profiling of pest resistance pathways are among the important research gaps identified in this review study. To fully realize the potential of PEOs, interdisciplinary cooperation between agronomy, entomology, plant biochemistry, toxicology, and socioeconomics is indispensable. By integrating traditional botanical knowledge with modern formulation science and policy innovation, PEOs offer a scalable, residue-free alternative for resilient agroecosystems and future-ready pest control.