Primary Metabolic Reprogramming Under Salinity Stress: Flux, Function, and Crop Resilience

Soil salinity is one of the most damaging abiotic stresses limiting crop productivity and global food security. As climate change accelerates soil degradation, freshwater scarcity, and irrigation-associated salt accumulation, there is an urgent need to understand the biochemical mechanisms that allow plants to maintain growth and yield under saline conditions. Research on salinity tolerance has traditionally emphasized ion transport, osmotic signaling, hormonal regulation, and stress-responsive transcriptional networks. However, primary metabolites, including soluble sugars, amino acids, organic acids, osmolytes, and tricarboxylic acid cycle intermediates, are among the earliest and most functionally important responders to osmotic and ionic stress. These metabolites do not merely reflect stress damage; instead, they actively shape tolerance by supporting osmotic adjustment, redox buffering, carbon-nitrogen balance, respiratory flexibility, and energy redistribution under ATP-demanding stress conditions.This Research Topic focuses specifically on primary metabolic reprogramming under salinity stress, aiming to consolidate emerging knowledge on primary metabolism as a core driver of plant salt tolerance rather than a passive downstream response. By focusing on sugars, amino acids, organic acids, osmolytes, respiratory intermediates, and carbon-nitrogen-redox coordination, it will clarify how plants reorganize central metabolism to survive, adapt, and maintain productivity in saline environments. Recent advances in targeted and untargeted metabolomics, stable-isotope tracing, fluxomics, respiratory phenotyping, and metabolic modeling now enable dynamic, pathway-level analysis beyond static metabolite inventories. This Research Topic therefore provides a focused platform for studies that move from descriptive metabolite accumulation toward mechanistic understanding of metabolic function, pathway regulation, and stress resilience, while bridging plant biochemistry, stress physiology, systems biology, and crop improvement.We welcome original research articles, reviews, mini-reviews, perspectives, and methodological papers addressing primary metabolic regulation under salinity stress. Contributions should be mechanistically anchored in primary metabolism and may include, but are not limited to, the following themes:• Osmolyte Biochemistry and Flux Dynamics: Studies on the biosynthesis, accumulation, turnover, and catabolic recycling of primary osmoprotective metabolites under salinity, including proline, glycine betaine, GABA, trehalose, sucrose, raffinose-family oligosaccharides, and other soluble sugars. Studies using isotope tracing, kinetic analysis, or flux-based approaches to quantify osmolyte dynamics are particularly encouraged.• Carbon Partitioning and Source-Sink Reorganization: Research examining how salinity reshapes carbon allocation between starch, soluble sugars, organic acids, roots, shoots, and reproductive sinks. Topics may include photosynthate redistribution, root-shoot metabolic coordination, carbohydrate remobilization, sink strength, and the metabolic basis of yield maintenance under saline environments.• Nitrogen Metabolism and Carbon-Nitrogen Trade-offs: Studies addressing salinity-induced changes in amino acid metabolism, nitrate and ammonium assimilation, ureide metabolism, the GS/GOGAT cycle, photorespiratory nitrogen recycling, and carbon-nitrogen coordination. Contributions linking nitrogen metabolic adjustment to ion toxicity, osmotic stress, growth limitation, or recovery responses are especially relevant.• Energy Metabolism, TCA Cycle Plasticity, and Redox Homeostasis: Research on salinity-driven remodeling of glycolysis, the TCA cycle, mitochondrial respiration, alternative respiratory pathways, ATP balance, NADH/NADPH homeostasis, and redox buffering. Studies connecting primary metabolic regulation with ROS control, mitochondrial flexibility, and stress survival are encouraged.• Halophyte-Glycophyte Comparisons and Crop Translation: Comparative studies identifying primary metabolic strategies that distinguish salt-tolerant halophytes from salt-sensitive glycophytes or crop species. Contributions may include cross-species metabolite profiling, conserved versus divergent metabolic responses, and translational insights for breeding, marker development, or crop improvement.• Primary Metabolism-Anchored Fluxomics, Modeling, and Systems Biology: Studies using metabolomics, fluxomics, isotope labeling, genome-scale metabolic models, flux balance analysis, kinetic modeling, or pathway simulations are welcome when they provide mechanistic insight into primary metabolic reprogramming under salinity. Broad descriptive multi-omics studies will be considered only when primary metabolic pathways, fluxes, or biochemical functions are central to the research question. Topic editors: Rafaqat Ali Gill, František Hnilička Source: https://www.frontiersin.org/research-topics/84371/primary-metabolic-reprogramming-under-salinity-stress-flux-function-and-crop-resilience