外源海藻糖对小麦幼苗耐盐性的影响

Effect of Exogenous Trehalose on Salt Tolerance of Wheat Seedlings

以盐敏感小麦品种鲁麦 15为材料 ,分别用完全 Hoagland营养液、15 0 mmol/ L Na Cl和 15 0 m mol/ L Na Cl+10 mm ol/ L 海藻糖处理小麦幼苗 ,测定小麦幼苗生长、离子含量、根系质膜 H+ - ATPase、SOD活性、MDA含量等指标 ,旨在探讨外源海藻糖在抗盐性中的作用 .结果表明 :外源海藻糖可明显缓解盐胁迫对小麦幼苗生长的抑制作用 ;明显提高 Na Cl胁迫条件下小麦幼苗叶片中 K+的含量 ,降低 Na+的含量 ,降低其 Na+ / K+ ;提高 Na Cl胁迫条件下小麦幼苗 SOD活性 ,降低 MDA的含量 ,降低细胞质膜透性 ,缓解根系质膜 H+ - ATPase活性抑制 .以上结果表明外源海藻糖可能通过增加活性氧清除能力、缓解质膜伤害、维持胞质离子稳态提高植物抗盐性 .

Growth,ionic content,activity of root plasma membrane H^+-ATPase,SOD activity and MDA content were determined in LM 15 (Triticum aestivum cv.Lumai 15) seedlings treated with Hoagland solution (control),150 mmol/L NaCl and 150 mmol/L NaCl+10 mmol/L trehalose respectively to study the effect of exogenous trehalose on salt tolerance.The results showed that exogenous trehalose obviously alleviated the inhibition of wheat seedlings' growth under salt stress;exogenous trehalose markedly increased the K^+ content and decreased Na^+ content in wheat seedlings' leaves,which led to the decrease of Na^+/K^+ ratio under salt stress.At the same time,SOD activity obviously increased,MDA content and permeability of plasma membrane significantly decreased due to adding trehalose to NaCl solution.Also,exogenous trehalose alleviated the decrease in the activity of root plasma membrane H^+-ATPase.The results suggested that exogenous trehalose increase plant salt tolerance by enhancing the ability of scavenging reactive oxygen species,alleviating the injury of plasma membrane and maintaining the ionic homeostasis in cytosol.