Integrated Multi-Omics Analysis Reveals the Involvement of Alanine, Aspartate and Glutamate Metabolism in Wheat Responses to Salt Stress.

Salt stress is frequently encountered by plants and is a major constraint on crop production. Wheat (Triticum aestivum L.) is a staple cereal crop that is important for human health and food security. However, the response mechanisms of roots from different wheat varieties to salt stress remain unclear. In this study, we analyzed the complex response mechanisms of the salt-tolerant variety Longjian 114 (LJ114) and the salt-sensitive variety Chinese Spring (CS) to salt stress using integrated transcriptomic and metabolomic analyses. The results showed that LJ114 maintained better growth and exhibited higher antioxidant enzyme activities and greater osmotic adjustment capacity under salt stress. Differentially expressed genes in LJ114 were predominantly enriched in flavonoid biosynthesis, alpha-linolenic acid metabolism, and zeatin biosynthesis under salt stress. Metabolomic profiling identified 1366 differential metabolites, with LJ114 specifically enriched in tyrosine metabolism, tryptophan metabolism, glycerophospholipid metabolism, and fatty acid metabolism under salt stress. Integrated analyses further highlighted ABC transporters and alanine, aspartate, and glutamate metabolism as hub pathways, with notably higher GAD expression and GABA accumulation under salt stress. These findings suggest new insights into the molecular mechanisms underlying wheat salt tolerance and propose potential candidate targets for enhancing crop salinity tolerance.