CO_2激光预处理对PEG6000胁迫下小麦幼苗根中抗氧化酶活性的影响

Effects of CO_2 Laser Pretreatment on Activities of Antioxidative Enzymes in Root of Wheat Seedlings under Water Stress

用CO2激光对小麦种子分别辐照0、1、3、5min,待其生长至12d时,用10%(W/V)PEG6000胁迫其幼苗,研究激光预处理对PEG6000水分胁迫下小麦幼苗根部脂质过氧化伤害的防护作用。结果表明,CO2激光预处理3min可使水分胁迫的小麦幼苗根部MDA、H2O2含量和O2.-产生速率显著降低(P<0.05),可显著提高(P<0.05)小麦幼苗根部SOD、POD、CAT、APX活性和根长、根干重。激光预处理3min可抑制由水分胁迫引起的小麦幼苗根部脂质过氧化作用。

The objective of this experiment was to study changes of antioxidative enzymes and lipid peroxidation in root of wheat seedlings exposed to water stress,as affected by CO2 laser （wavelength 10600 nm,power density 20.1 mW/mm2） pretreatment.Wheat seed embryos were exposed to CO2 laser radiation for 0,1,3 min and 5 min,respectively,and when the seedlings were 12 days old they were treated with 10% （W/V） PEG6000 solution for 8 days.Changes in the concentration of malondialdehyde （MDA） and hydrogen peroxide （H2O2）,the production rate of superoxide radical （O- .2） and superoxide dismutase （SOD）,peroxidase （POD）,catalase （CAT）,ascorbate peroxidase （APX） activities of root and the growth parameters of root （root length and root dry weight） were measured to test the effects of laser pretreatment.The results showed that suitable laser pretreatment of embryos had positive effect on the root of wheat seedlings subjected to water stress,such as decreasing the concentration of MDA and H2O2,the production rate of O- . 2 and increasing the activities of SOD,POD,CAT and APX of root and root length and root dry weight.It was suggested that those changes in MDA,H2O2 and O2,anti-oxidative enzymes of root and root growth and development were responsible for protection wheat against water induced oxidative damage.