外源一氧化氮对NaCl胁迫下番茄幼苗活性氧代谢的影响

研究了在100 mmol/L NaCl胁迫下，外源NO供体硝普钠（SNP）处理对耐盐性不同的2个番茄品种（沪番‘1480’和沪番‘2496’）幼苗叶片活性氧（ROS）水平和保护酶活性的影响。结果表明，外源NO提高了盐胁迫下SOD、POD、CAT和APX活性，AsA和GSH含量以及脯氨酸和可溶性糖含量，降低了MDA含量和O2- 产生速率；与耐盐品种‘1480’相比，NO处理对盐敏感品种‘2496’效果更明显。表明外源NO通过促进盐胁迫下保护酶活性、抗氧化剂和渗透调节物质的提高，降低ROS水平，缓解NaCl胁迫对番茄幼苗生长的抑制作用，增强植株的耐盐能力。

Effects of exogenous nitric oxide on reactive oxygen metabolism in tomato seedlings under NaCl stress

Effects of NO sodium nitropprusside (SNP, an exogenous nitric oxide donor) on reactive oxygen species and protective enzyme activities were studied in the leaves of two tomato cultivars, ‘Hufan1480’ and ‘Hufan2496’, under 100 mmol/L NaCl stress. Results showed that nitric oxide not only increased the activities of SOD, POD, CAT and APX, but also increased the concentration of AsA and GSH, and of proline and soluble sugar in leaves. Results also showed decreased MDA concentrations and O2- producing rate under NaCl treatments. The effect of NO treatment in salt-sensitive ‘Hufan2496’ was more effective than that in salt-tolerant ‘Hufan1480’ under salt stress. Results suggested that NO could increase protective enzymatic activities, contents of osmotic adjustment substances and antioxidants under NaCl stress. Thus, NO played an important role in enhancing the resistance to NaCl stress of tomato seedlings and elevated the salt tolerance of plants through keeping low ROS contents.