Pelargonic Acid: From Historical Uses to Future Perspectives in Sustainable Agriculture

Pelargonic acid (PA), or nonanoic acid, is a saturated fatty acid with a nine-carbon chain and low toxicity. Although initially applied in processes, PA has gained relevance in agriculture as a bioherbicide, driven by demand for sustainable alternatives to synthetic herbicides. Recently approved for agricultural use in several countries, PA has demonstrated effective control of a range of weed species; however, its agricultural use faces limitations, such as complexity of synthesis, high volatility, degradation in field, and need for frequent applications. As a contact herbicide, PA acts through rapid membrane disruption that underlies its burndown effect but requires high application rates and repeated treatments in systems. This review provides an analysis of PA, addressing its relevance and consolidation as a bioherbicide with sustainability goals, discussing transition from conventional herbicides to molecules. It highlights that nanotechnology-based approaches can address limitations, improving efficacy and persistence, supporting integration into management.