Emerging Plant Hormones: Opening up New Lanes to Face Abiotic Stresses

Abiotic stressors such as drought, salinity, extreme temperatures and heavy metal toxicity represent significant obstacles to global agricultural productivity. Next-generation plant hormones, including Jasmonic Acid (JA), Strigolactones (SLs) and Melatonin, have been identified as essential regulators of stress adaptation. These hormones are instrumental in modulating stress-responsive signalling pathways, thereby enhancing plant resilience through various physiological and molecular mechanisms. Jasmonic Acid (JA) serves as a vital hormone in plant defence, orchestrating responses to oxidative stress, facilitating stomatal closure and promoting the production of secondary metabolites to counteract drought and salinity stresses. Strigolactones (SLs) influence root architecture and symbiotic relationships, thereby improving water and nutrient absorption in nutrient-deficient and saline environments. Melatonin, recognised for its potent antioxidant properties and role as a signalling molecule, mitigates oxidative damage, optimises photosynthetic efficiency, and boosts tolerance to abiotic stress through interactions with abscisic acid (ABA) and auxins. The application of advanced biotechnological tools, such as CRISPR/Cas genome editing and nanoparticle-based hormone delivery systems, presents new opportunities for refining hormone regulation in crops. A comprehensive understanding of the interactions between JA, SL, and melatonin with other plant hormones will facilitate the development of stress-resilient crops. These cutting-edge strategies hold significant potential for improving agricultural productivity and sustainability in response to the stresses induced by climate change.