Unlocking nature's stress buster: Abscisic acid's crucial role in defending plants against abiotic stress*

The main obstacle for sustained supply of agricultural products and feeding the globe in the coming years is abiotic stress. Plants typically shorten their developmental processes under stress, which eventually has a negative impact on production. A key phytohormone that plays crucial role in combating abiotic stress is abscisic acid (ABA). ABA plays a significant role in absorbing stress signals and guiding subsequent stress responses. For an outcome, plants must consistently control ABA levels in response to shifting environmental factors. In addition to helping plants adapt to diverse conditions like drought, salt, temperature stress, ABA also controls a number of physiological functions, including stomatal opening and protein synthesis. A variety of defense mechanisms against stress are regulated by ABA, which is produced in various organs in response to stressful situations. These defense mechanisms include controlling stomatal aperture and the expression of genes that confer resistance against environmental stresses. Based on the current available literatures, this review provides insights of ABA's function in plants in context of abiotic stresses, with a focus on its synthesis, signaling pathways, regulatory functions, impact on root architecture, control over stomatal movement, and its intricate interactions with other phytohormones.