摘要
水杨酸和一氧化氮在植物研究中都被认为是调控一系列生理过程的重要内源信号分子。采用药理学和生物化学的方法,研究发现外源水杨酸溶液对盐诱导小麦根部组织的氧化伤害具有保护作用。盐处理(150mmol/L)显著提高根部组织的脂质过氧化水平以及抑制根的生长;同时添加100μmol/L的水杨酸(SA)不仅可以有效的降低脂质过氧化水平以及部分增加根的生长,而且激活了包括SOD、POD和APX等抗氧化酶的活性。此外,一氧化氮(NO)供体硝普钠(SNP)处理能得到与上述SA处理相类似的生物学表型。进一步的研究发现,SA的这种生物学功能很可能与NO有关,因为结合采用NO专一性清除剂cP-TIO的处理则不同程度地逆转了SA的各种缓解效应。更重要的是,SA能通过模拟SNP的作用来诱导小麦幼苗根部大量释放NO。上述研究表明,SA通过NO信号上调小麦幼苗根部抗氧化防护来提高耐盐性。
In the present study, both Salicylic （SA） acid and nitric oxide （NO） were proven as signaling molecules in regulating a serial of physiological processes in plants. Using pharmacological and biochemical approaches, we evaluated the protective effect of exogenous salicylic acid against salt-induced oxidative damage in the roots of wheat seedling. Plants exposed to salt （150mmol/L NaCl） exhibited the significant increase of lipid peroxidation as well as the inhibition of root growth. However, SA （100μmol/L） supplementation to NaCl （150mmol/L） treated plants effectively not only reduced the lipid peroxidation and partially increased the root growth, but also activated anti-oxidant enzyme, including superoxide dismutase （SOD）, activities.guaiocol peroxidase （POD） and ascorbate peroxidase （APX）, which was also mimicked by the application of the nitric oxide （NO） donor sodium nitroprusside （SNP）. Further analyses showed that the above ameliorating effects of SA were specific and related to NO, because the specific scavenger of NO 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt （cPTIO） differentially blocked the above effects. Additionally, SA was able to mimic the effect of SNP by strongly increasing NO release in the roots after daily treatment. Taken together, above results suggest that SA might confer an increased tolerance to salinity stress by enhancing antioxidant defense in wheat seedling roots, which were partially mediated by NO signal.
出处
《中国农学通报》
CSCD
2008年第9期248-252,共5页
Chinese Agricultural Science Bulletin
基金
安徽省高校青年教师科研资助计划项目(2006jql120)
安徽农业大学2008年度校长青年基金立项项目
关键词
小麦幼苗
水杨酸
一氧化氮
抗氧化防护
wheat seedling, salicylic acid, nitric oxide, antioxidant defense
