外源H_2O_2对大蒜试管苗玻璃化及活性氧代谢动态变化的影响

以大蒜品种"二水早"为试材,研究不同浓度外源H2O2胁迫对大蒜试管苗玻璃化的发生及活性氧代谢动态变化的影响,探讨氧化胁迫对大蒜试管苗玻璃化的诱导效应及其机制。结果表明:H2O2胁迫影响试管苗正常生长,SOD、POD、CAT和APX活性先升高后降低,变化幅度较大,细胞内保护酶调节功能紊乱,MDA和电解质渗透率水平明显提高,2.0 mmol/LH2O2处理显著促进试管苗玻璃化现象的发生。说明氧自由基胁迫可诱导试管苗玻璃化,脂质过氧化可能是试管苗玻璃化的直接原因。

Effects of Exogenous H2O2 on Hyperhydricity and Reactive Oxygen Metabolism Dynamics of Garlic Test-tube Plantlets

Using garlic variety "Ershuizao" as the tested material,the effects of different concentrations of exogenous H2O2 stress on the occurrence of hyperhydricity and dynamics of reactive oxygen metabolism in garlic test-tube plantlets were studied in this paper to investigate the mechanism and inductive effect of H2O2 stress on hyperhydricity.The results showed that the exogenous H2O2 influenced the normal growth of plantlets.After being treated with H2O2,the activity of SOD,POD,CAT and APX in garlic plantlets increased at first and then decreased with large variation ranges;the regulation function of protective enzymes appeared disorder;MDA content and the rate of electrolyte leakage were obviously increased.The hyperhydricity of garlic test-tube plantlets was significantly accelerated by 2.0 mmol/L H2O2 stress.The results suggest that the oxygen free radicals can induce the occurrence of hyperhydricity,and the lipid peroxidation may be the direct reason of leading to hyperhydricity of test-tube plantlets.