Integrated Strategies for Saline-Alkali Soil Remediation and the Development of Salt-Alkali-Tolerant Crops

Soil salinization is a major threat to global food security and sustainable agriculture, soil salinization affects approximately 8.31 × 10⁸ hm² of soil resources globally. The remediation and productive use of saline-alkali land have therefore become urgent global challenges. This review summarises the classification and global distribution of saline-alkali soils and critically compares physical, chemical, microbial, and phytoremediation strategies. It then examines the physiological, cellular, and molecular mechanisms that support plant salt and alkali tolerance, with emphasis on ion transporters that maintain ion homoeostasis, the interactions among phytohormone pathways, including ABA, JA, and GA, in balancing growth and stress responses, and the contribution of epigenetic regulation to stress adaptation. Although substantial progress has been made in identifying salt-alkali-tolerance genes and developing soil amendments, a considerable gap remains between laboratory-based studies and field-level yield improvement. Future progress will depend on moving from single-factor seedling assays to field-based yield validation, combining CRISPR/Cas-mediated genome editing with microbiome engineering, and addressing the socioeconomic feasibility of large-scale remediation. Integrated strategies that link soil improvement, crop genetics, microbial regulation, and field management can provide both theoretical insights and practical guidance for sustainable agriculture in saline-alkali environments.