Mechanistic insights into nitric oxide signaling in shaping root architecture under challenging environments

Global climate change continues to interrupt temperature and precipitation patterns, intensifying soil degradation and abiotic stresses that severely impair plant growth and productivity. As the demand for sustainable food systems grows combined with a rising global population, understanding how crops acclimatize to environmental stresses is important. Roots play an essential part in this adaptation by modulating dynamic organs for anchorage, nutrient acquisition, and as primary perception of abiotic stress. Understanding root architecture and their plasticity is reflected in the modulation of root system architecture (RSA), a key determinant of stress resilience. Nitric oxide (NO) is a gasotransmitter that has emerged as a crucial regulator of plant development and stress responses. NO interacts with reactive oxygen species (ROS) and phytohormones to modulate root traits such as lateral root formation, root hair development, and organogenesis. It employs its regulatory effects through post-translational modifications, influencing antioxidant enzyme activity and gene expression. Despite significant progress, the biochemical and molecular mechanisms underlying NO-mediated RSA modulation remain complex and partially understood. This review discusses recent insights into NO multifaceted role in root development under stress, highlighting its interplay with ROS and hormonal signaling networks. Likewise, highlights key knowledge gaps critical to optimizing the role of NO in crop improvement, while emphasizing how emerging technologies, such as single-cell transcriptomics, redox-sensitive biosensors, and high-resolution live-cell imaging enable deeper insights into NO-ROS interactions in RSA remodeling. These innovations hold promise for engineering climate-resilient crops with enhanced root traits and adaptive capacity, supporting future sustainable agriculture under changing environmental conditions.