外源H2O2对小麦幼苗耐盐性的调节作用

摘要

The chlorophyll content,MDA content,soluble sugar content and GSH content were determined at the 2nd ,4th, 6th and 8th day, respectively, after treatments of Hoagland solution, Hoagland solution+150mmol/L NaCl, Hoagland solution - 150 mmol/L NaCl+ 10 μmol/L H2O2 and Hoagland solution+ 10 μmol/L H2O2. The addition of exogenous H2O2 (10μmol/L) increased the wheat seedling chlorophyll content (by 8.27% , 32.57% ,10.19% and 4.86%) and GSH contents (by 3.09%,23.97%,5.85% and 2.11%), dramatically increased soluble sugar content (by 14.58 %, 8.43 %, 16.68 % and 5.8 %, P＜0.05)and dramatically decreased MDA content (by 17.53% ,14.04% ,4.75% and 8.47% ,P＜0.05) compared to the salt stressed (Hoagland solution+NaCl) group on the 2nd , 4th, 6th and 8th day, respectively, after treatments. Exogenous H2O2 (10 μmol/L) accelerated the maximum accumulation chlorophyll and GSH contents in NaCl stressed condition while decelerated the maximum accumulation content of MDA. Exogenous H2O2 enhanced wheat seedling salinity tolerance.%以'高原448'小麦品种为材料,分别测定了4个处理(Hoagland营养液、Hoagland营养液+150 mmol/LNaCl、Hoagland营养液+150 mmol/L NaCl+10 μmol/L H2O2和Hoagland营养液+10 μmol/L H2O2)的小麦幼苗在第2、4、6、8天叶片叶绿素、丙二醛、可溶性糖和还原性谷胱甘肽含量.结果显示:外源H2O2提高了NaCl胁迫下4个时段小麦幼苗的叶绿素含量(8.27%、32.57%、10.19%、4.86%)及还原性谷胱甘肽含量(3.09%、23.97%、5.85%、2.11%),显著提高了可溶性糖含量(14.58%、8.43%、16.68%、5.8%,P＜0.05),而显著降低了其丙二醛含量(17.53%、14.04%、4.75%、8.47%,P＜0.05).外源H2O2(10μmol/L)使NaCl胁迫下叶绿素含量和还原性谷胱甘肽含量峰值提前,同时推迟了丙二醛峰值出现的时间.研究表明,外源H2O2通过提高叶片叶绿素、可溶性糖和还原性谷胱甘肽含量以有效地增强小麦幼苗的耐盐性.