Foliar Stimulants: A Sustainable Strategy for Enhancing Plant Resilience to Abiotic and Biotic Stresses

The increasing frequency of abiotic and biotic stresses, such as drought, salinity, high temperatures, and pathogen attacks, threatens global agricultural productivity and food security. To address this, applying stimulants through foliar sprays has become a promising, sustainable method to boost plant resistance and improve crop yields. This review discusses the mechanisms, applications, and effects of using foliar stimulants, including amino acids, humic substances, phytohormones, vitamins, micronutrients, and plant extracts. Foliar application allows rapid nutrient absorption through stomatal openings and the cuticle, resulting in systemic movement via both apoplastic and symplastic pathways. Once absorbed,…