Towards plant salinity tolerance-implications from ion transporters and biochemical regulation

Crop production is adversely affected by soil salinization and therefore, development of crop cultivars with salt tolerance is crucial for better utilization of saline soil and enhancement of sustainable agricultural productivity. High salt concentration induces various physiological and biochemical responses in plants, while plants employ mechanisms in adaptation to salinity stress at cellular, metabolic and whole-plant levels, including stress signalling, ion balancing, osmotic regulation and antioxidant protection. In this review, we discuss the signalling pathways and key mechanisms of Na+ detoxification mediated by ion transporters and antiporters, and make an overview of practical strategies and methodologies for functional characterization of high-affinity potassium transporters. In addition, recent research advances in improvement of plant salt tolerance through biochemical regulation, particularly alleviating salt stress by exogenous application of gibberellins and nitric oxide, are reviewed. We also propose key research perspectives that remain to be addressed in future.