外源一氧化碳对干旱胁迫下水稻幼苗抗氧化系统的影响

以水稻(Oryza sativa L.) 品种‘D奇宝优1号'幼苗为材料,采用20%聚乙二醇(PEG-6000)模拟水分胁迫,研究外源一氧化碳(CO)对干旱胁迫下水稻幼苗抗氧化能力的影响,以探索CO提高水稻幼苗抗旱性的机制.结果显示,CO供体高铁血红素(Hematin,H)显著降低干旱胁迫下水稻幼苗叶片质膜相对透性和丙二醛(MDA)含量,提高脯氨酸和可溶性蛋白的含量,不同程度地促进叶片中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)的活性,而CO清除剂血红蛋白(Hemoglobin,Hb)则逆转CO供体对干旱胁迫下水稻幼苗氧化损伤的缓解效应.由此表明,外源CO能通过调整保护酶活性和渗透调节物质含量来提高水稻幼苗的抗氧化能力,有效增强其抗旱性.

Effect of Exogenous Carbon Monoxide on Antioxidative System in Rice Seedlings under Drought Stress

To investigate the protective effect of exogenous carbon monoxide (CO) against drought-induced oxidative damage,CO donor hematin(H) and CO scavenger hemoglobin (Hb) were applied in rice (Oryza sativa L.) seedlings under 20% PEG-6000 of water stress.The results showed that exogenous CO could cause the rice-seedling leaves to increase their proline contents and soluble protein contents,whereas decrease their MDA contents and membrane relative permeability,and accelerate differentially the activities of superoxide dismutase (SOD),catalase (CAT) and peroxidase (POD).The effects of CO could be reversed when CO scavenger Hb is added.It confirms that CO may enhance resistance against drought stress through raising anti-oxidative capability in rice seedling.