论文部分内容阅读
为探讨外源活性氧物质(ROS)引起试管苗玻璃化,以及活性氧清除剂对试管苗玻璃化的缓解效应和机理,以大蒜品种‘二水早’试管苗为材料,研究外源过氧化氢(H2O2)及H2O2+活性氧清除剂抗坏血酸(AsA)处理下试管苗玻璃化及活性氧代谢的变化。结果表明:外源H2O2处理使大蒜试管苗内源超氧阴离子产生速率和H2O2含量提高,玻璃化率和玻璃化程度提高。玻璃化现象的发生较内源大量发生滞后,与H2O2显著积累同步。外源H2O2处理0~8d,超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性有上升趋势并显著高于对照,但在8d后抗氧化酶活性或者下降(SOD、CAT),或增加缓慢(POD),而内源抗氧化物质AsA含量在处理8d时显著低于对照。在外源H2O2处理的同时添加外源AsA,因外源H2O2引起的内源的产生和H2O2的积累减少,SOD、POD、CAT等抗氧化酶活性保持持续上升趋势,并在处理后期高于添加H2O2的处理及对照,内源AsA含量保持较高水平并显著高于外源H2O2处理;同时玻璃化率增加缓慢。综上所述,外源H2O2可提高大蒜试管苗内源的产生速率和H2O2含量,降低抗氧化系统的抗氧化能力,进而导致试管苗玻璃化加重;添加外源抗氧化物质AsA可缓解的产生和H2O2的积累,对试管苗玻璃化发生有控制效果。
In order to investigate the vitrification effect of vitrification induced by exogenous reactive oxygen species (ROS) and vitrification of reactive oxygen scavenger (ROS) on vitro plantlets, the effects of exogenous peroxidation Changes of Vitrification and Active Oxygen Metabolism in Test - tube Plantlets Exposed to Hydrogen (H2O2) and H2O2 + Active Oxygen Scavenger Ascorbate (AsA). The results showed that the exogenous H2O2 treatment increased the production rate of endogenous superoxide anion and the content of H2O2 in garlic plantlets, and the vitrification rate and vitrification degree increased. The occurrence of vitrification lagged significantly compared with that of endogenous species, with the significant accumulation of H2O2. The activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in the exogenous H2O2 treatment increased from 0 to 8 days and was significantly higher than that of the control, but after 8 days, the activities of antioxidant enzymes Or decreased (SOD, CAT), or increased slowly (POD), while the endogenous antioxidant AsA content was significantly lower than the control 8d treatment. Exogenous AsA was added simultaneously with exogenous H2O2 treatment, the production of endogenous exogenous H2O2 and the accumulation of H2O2 decreased, the activities of antioxidant enzymes such as SOD, POD and CAT kept increasing, and were higher than those of the control H2O2 treatment and control, the content of endogenous AsA remained higher and significantly higher than the exogenous H2O2 treatment; at the same time the rate of increase of glass is slow. In summary, exogenous H2O2 can increase the production rate and H2O2 content of garlic root exudates, reduce the antioxidant capacity of the antioxidant system, and lead to vitrification of the plantlets; exogenous anti-oxidant AsA can alleviate Production and accumulation of H2O2, vitrification of test tube seedlings have a control effect.