腐胺对盐胁迫下小麦幼苗根中活性氧代谢的影响

以小麦（T.aestivm L.）＂陇春23号＂为实验材料,测定了外源腐胺（Put）对NaCl胁迫条件下,小麦根细胞的膜透性、丙二醛（MDA）含量、活性氧（ROS）的含量、抗氧化酶活性,结果表明外源Put处理使NaCl胁迫下小麦根中细胞膜透性降低,MDA含量减少,抗氧化酶（CAT,SOD,APX,POD）的活性升高,O2.-的产生减少,但H2O2的含量升高。进一步测定二胺氧化酶（DAO）和多胺氧化酶（PAO）的活性,结果 DAO和PAO的活性升高,表明外源腐胺能通过提高抗氧化酶的活性减轻NaCl对小麦根的氧化伤害,但H2O2在此实验中不是对小麦根起伤害作用,可能作为信号分子起作用。

Effects of exogenous application of putrescine on active oxygen metabolism in the wheat roots under salt stress

The effect of exogenous application of putrescine on membrane permeability, content of MDA, active oxygen contents, and antioxidase activity＇in wheat roots under salt stress were studied. The results showed that under salt stress, exogenous putrescine reduced the membrane permeability and content of MDA. The activities of CAT, SOD, APX and POD, the conten of H202 were increased, while the content of 02＂ -were decreased. The results suggest that exogenous application of putrescine could alleviate salt-induced membrane injury of wheat roots by increasing the antioxidase activity. Furthermore, the activities of DAO and PAO were studied. Exogenous application of putrescine increased the activities of DAO and PAO. It implied that H202 was not acted as a injury factor in this experiment, but as a signaling molecule.