Salinity tolerance in wheat (Triticum aestivum L.): physiological mechanisms, grain quality responses, and advances in integrated breeding and management strategies

Abstract

Salinity stress in wheat (Triticum aestivum L.) represents a major challenge for agricultural sustainability, grain quality, and global food security, particularly in arid and semi-arid regions increasingly affected by soil salinization and climate variability. This systematic review aimed to synthesize current knowledge on the physiological, biochemical, molecular, microbiological, and technological mechanisms underlying salinity tolerance in wheat and to evaluate how these complementary processes can be integrated to improve grain quality, stress resilience, and the development of climate-resilient wheat production systems under saline environments. Using a PRISMA-guided selection framework, literature published between 2018 and 2025 was systematically screened across major scientific databases, resulting in the identification of 408 records, from which 142 peer-reviewed studies were retained following predefined screening, eligibility, and quality-assessment criteria. Bibliometric mapping with VOSviewer was further applied to identify dominant research themes linking salinity physiology, grain-quality dynamics, microbiome-assisted mitigation, and advanced breeding technologies. The reviewed evidence indicates that salinity-induced reductions in wheat productivity are primarily associated with ionic toxicity, osmotic imbalance, oxidative stress, photosynthetic impairment, and disruption of metabolic and nutritional homeostasis, ultimately affecting grain protein accumulation, starch biosynthesis, mineral balance, and technological quality traits. Current mitigation approaches increasingly emphasize integrated strategies involving organic amendments, beneficial rhizosphere microorganisms, ion-homeostasis regulation, and precision agronomic management. In parallel, advances in genomics-assisted breeding, multi-omics integration, CRISPR/Cas genome editing, high-throughput phenotyping, remote sensing, and AI-assisted predictive breeding are improving candidate-gene prioritization and genotype-to-phenotype prediction under saline environments. This review integrates PRISMA-based screening with bibliometric analysis to provide a structured and mechanistic synthesis linking salinity stress physiology, grain-quality responses, microbiome-assisted approaches, sustainable soil-management practices, and precision breeding technologies. By adopting a cross-scale perspective, this review concludes that integrating physiological, microbiome-assisted, agronomic, and advanced breeding approaches is essential for developing climate-resilient wheat production systems under increasing soil salinity.