Salinity stress in plants: Growth, photosynthesis and adaptation review

Salinity is a significant abiotic stress that decreases plant growth and productivity in many parts of the world due to increased use of poor-quality water for irrigation and soil salinization. Salinity stress negatively impacts agricultural yields globally, affecting production for both subsistence and financial gain. Salt stress affects every aspect of crop growth, inhibiting plant growth and reducing the fresh and dry weight of roots, stems, and leaves. It also decreases leaf expansion and alters leaf morphology. Additionally, salt stress represses photosynthesis and disrupts plant ion homeostasis, leading to metabolic imbalances and oxidative stress. The adaptation or resistance of plants to salinity stress involves complex physiological features, metabolic pathways, and networks of molecules or genes. To develop salt-tolerant plant varieties for salt-affected areas, a comprehensive understanding of plant responses to salinity stress at various levels and an integrated approach combining molecular, physiological, and biochemical techniques are necessary. Recent research has identified many adaptive responses to salinity stress at genetic, cellular, metabolic, and physiological levels. However, the mechanisms underlying salinity tolerance are still not fully understood. In this review, we investigate the damage caused to plants by environmental salt stress and explore how plants tolerate this stress at the molecular level.