外源H2O2对小麦幼苗耐盐性的调节作用

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 10μmol/L H2O2和Hoagland营养液 10μmol/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.

Regulation of Exogenous Hydrogen Peroxide on Wheat Seedling Salinity Tolerance

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.