Interplay among hormones, antioxidants, and redox signaling in abiotic stress responses

Abiotic stresses are major limiting factors in plant development, delaying growth and reducing crop yield. These stressors induce the formation of reactive oxygen species (ROS), which can be harmful at high concentrations but also act as signaling molecules. Plants display robust antioxidative machinery to scavenge excess ROS and maintain nontoxic ROS levels. Plant hormones, specialized signaling molecules, are not only essential in plant growth and development, but also transducing stress signals, profoundly affecting the antioxidative machinery and triggering plant adaptive responses. In this context, respiratory burst oxidase homologous proteins are essential hubs that mediate phytohormone-induced ROS production, linking phytohormonal signals to important processes, such as stomatal closure. This review highlights the significant role of abscisic acid, jasmonic acid, salicylic acid, and brassinosteroids in enhancing antioxidative responses under abiotic stress conditions. Additionally, we emphasize the importance of redox post-translational modifications involved in hormone signaling. • Phytohormones regulate antioxidant machinery and plant tolerance. • RBOHs serve as hubs linking phytohormones and H 2 O 2 signaling. • Redox post-translational modifications modulate phytohormone signaling pathways.