盐胁迫下红海榄脯氨酸与活性氧代谢特征研究

系统地研究了盐胁迫下红海榄脯氨酸和活性氧的代谢特征.结果表明:1)脯氨酸含量随着盐度的增加出现先降后升的趋势,当盐度达到10时,其含量达最低.在无盐和高盐环境下脯氨酸的大量积累是植物细胞的适应性反应,其含量的高低不宜作为红海榄的抗盐性指标.2)超量脯氨酸积累会影响CO2的固定,降低叶片细胞内有机物的合成量,导致高盐胁迫下叶片的肉质化程度降低.3)红海榄SOD活性随盐度呈先降低后升高的趋势,其超氧负离子释放速率与SOD活性呈负相关.在中高盐度下,其POD、CAT活性迅速增加,可有效地清除由SOD与O 2产生的H2O2,避免了由于盐胁迫导致活性氧增加而对质膜造成的伤害.

Study on the Characteristic of Proline Accumulation and Active Oxygen Metabolism in Rhizophora stylosa under Salt Stress

Effects of salinity on proline content and active oxygen metabolism of Rhizophora stylosa were investigated. The results are as following: 1)As salinity increases, proline accumulation of Rhizophora stylosa firstly decreases then increases. At salinity of 10, proline accumulation reaches its lowest point, which shows proline content cannot act as an index to reflect the stress tolerance of Rhizophora stylosa. Proline accumulation under high salinity and 0 salinity results from the disorder of cell structure and function. 2)Excessive proline probably reduces the succulence of their leaves.3)The activity of superoxide dismutase(SOD) in Rhizophora stylosa has a negative correlation with the releasing of superoxide anion. The activity of peroxidase(POD) and catalase(CAT) increases under high salinity, which can eliminate H_2O_2 produced by SOD and avoid the damage to membrane.