叶片外源施加硝普钠对渗透胁迫下花生幼苗生长及根系抗氧化系统的影响

The Influence of Folia Scribbling SNP on Antioxidant System of Peanut Roots under PEG Stress at Seedling Stage

一氧化氮(NO)作为一种生物体内重要的信号分子,参与植物生长发育调控和对生物与非生物环境胁迫的应答反应。本试验选取四种NO响应类型,通过在15%PEG胁迫条件下对叶片施加SNP,研究并分析外源NO供体SNP对不同类型花生生长及抗氧化特性的影响。结果表明:NO处理对低含量高诱导品种沂南四粒糙和高含量高诱导品种花育22的干重促进作用最大。NO处理对不同品种根系抗氧化指标的影响也不尽相同。NO和PEG共同处理后,花育22和沂南四粒糙SOD和CAT活性变化不大,POD活性增加明显,MDA和O2-产生速率大幅度降低。而其余两个品种NO处理不利于维持胁迫下抗氧化酶的高活性。根系NO含量增加能够改变胁迫下CAT活性增加的趋势,同时缓解PEG胁迫对地上部物质积累量的影响。

Nitric oxide （NO） is an important signaling molecule in vivo, participating in the regulation of plant growth and development, and responses of plants to biotic and abiotic environmental stresses. 4 NO response types were selected to treat leaves with SNP, and the effects of exogenous NO donor SNP on growth and antioxidant properties of different types of peanuts were discussed, in order to provide a theoretical basis about the SNP function. The main findings were as follows. NO treatment promoted dry weight of Yinansilicao and Huayu22 greatly under PEG stress. The effects of NO treatment on antioxidant index in leaves of different cultivars under the stress were different. After SNP application, the difference of SOD and CAT activity of Huayu22 and Yinansilicao of the 2 water stress treatments was not significant, but POD activity increased obviously; NO treatment distinctly reduced MDA content and O2- production rate in roots. While NO treatment was not conductive to keep high activity of antioxidant enzymes of other 2 cultivars. Correlation analysis showed that the increase of NO content in roots could alter the increase trend of CAT activity and mitigate the impact of PEG on shoots under PEG stress.