Priming mediated stress and cross-stress tolerance in plants: Concepts and opportunities

Abstract Plants are often exposed simultaneously to several stresses, and the ability to perceive the stresses and activate the proper responses is crucial for the survival of the plant. Plants possess an intricate network of stress signals including signaling pathways, hormones, and defensive proteins, which activate the most suitable defensive mechanisms against the stresses. This immune system can be stimulated to activate the plant defenses and get them ready for subsequent stresses. In this way, cross-tolerance and priming have emerged as potential solutions for enhancing crop resilience. Cross-tolerance is induced by a mild primary stress, which activates common defenses that reinforce tolerance to different stresses. On the other hand, the application of priming agents prepares the plant to respond faster and more effectively against future stresses. Both mechanisms can improve the resistance of plants against a broad number of stresses simultaneously, providing an effective approach for plant tolerance to environmental perturbations.