Succinic Acid: A Metabolic Enhancer for Plants Under Stress

One important metabolic signal that aids in plant adaptation to environmental stressors is succinic acid (SUA), a crucial intermediate of the tricarboxylic acid (TCA) cycle. SUA is essential for redox regulation, osmoprotection, metabolic rewiring, and stress-responsive gene expression in addition to its traditional function in cellular respiration. SUA strengthens antioxidant defenses, stabilizes membranes, controls ion balance, and primes immune responses in the face of biotic challenges like bacterial and fungal infections as well as abiotic stresses like drought, salinity, heat, cold, and heavy metals. According to recent studies, SUA functions as a signaling molecule that interacts with phytohormones, beneficial microbes, and transcriptional networks. This chapter gives a full picture of the biochemical, physiological, and molecular ways that SUA makes organisms more resistant to both abiotic and biotic stressors. Emphasis is placed on its exogenous application strategies, molecular targets, and relevance in sustainable agriculture.