Nanoparticles as Potential Eustressors in Plants

In recent years, the acceleration of climate change and the growing demand for higher-quality food to meet the needs of an expanding population have become pressing challenges. Nanotechnology has emerged as a promising tool in agriculture, particularly through the application of nanoparticles (NPs). Recent studies highlight their potential to enhance plant performance, improve resistance to environmental stresses, and act as eustressors—stimuli that activate beneficial adaptive responses. Nanoparticles have been shown to stimulate plant defense systems (elicitation), promote growth and productivity, and improve crop quality by modulating physiological and biochemical pathways. Their role in enhancing adaptive capacity under diverse stress conditions makes them valuable candidates for sustainable agricultural strategies. However, a critical knowledge gap remains: the definition of eustress dose intervals. Establishing these thresholds is essential for maximizing the positive effects of NPs while minimizing risks. Finally, the need to define safe eustress dose intervals is highlighted as a critical step toward maximizing agricultural benefits while minimizing ecological and health risks.