Physiological responses and adaptive strategies of wheat seedlings to salt and alkali stresses

Effects of salt (NaCl : Na₂SO₄) and alkali (NaHCO₃ : Na₂CO₃) stresses on the contents of inorganic ions and organic solutes in wheat shoots were compared to explore the physiological responses and adaptive strategies of wheat to these stresses. Wheat significantly accumulated Na⁺ and simultaneously accumulated Cl^?, soluble sugars and proline to maintain osmotic and ionic balance under salt stress. Compared with salt stress, the high pH from alkali stress enhanced Na⁺ accumulation and affected the absorption of inorganic anions. To maintain ionic and osmotic balance, wheat accumulated organic acids, soluble sugars and proline. The accumulation of Cl^? and organic acids was the main difference in the physiological responses and adaptive mechanisms to salt and alkali stresses, respectively.