摘要
采用营养液培养试验,通过添加不同浓度(0.05、0.1、0.2、0.3mmol·L-1)的硝普钠(SNP)作为NO供体,研究外源NO对NO3-胁迫下黄瓜幼苗生长及叶片抗氧化酶活性的影响.结果表明:140mmol·L-1NO3-胁迫下,外加0.1mmol·L-1SNP处理1d和7d后,黄瓜幼苗叶片中SOD、CAT和APX活性显著升高;MDA含量显著降低,可溶性蛋白含量增加,说明外加0.1mmol·L-1SNP增强了黄瓜幼苗对活性氧的清除能力,降低了膜脂过氧化程度,幼苗生长势增加,对高浓度NO3-胁迫的抗性增强;当SNP浓度达0.3mmol·L-1处理7d后,SOD、POD、CAT和APX活性均开始降低,MDA含量增加,黄瓜幼苗受害加重.外加一定浓度(0.1～0.2mmol·L-1)的外源NO可缓解NO3-胁迫对黄瓜幼苗的影响.
In this study,cucumber seedlings were cultivated in nutrient solution added with different concentration （0.05,0.1,0.2,and 0.3 mmol·L^-1） sodium nitroprusside （SNP） as nitric oxide （NO） donor to study the effects of exogenous NO on the growth of cucumber seedlings and the activities of antioxidant enzymes in cucumber leaves under NO-3 stress. Under the stress of 140 mmol·L^-1 NO-3,treating with 0.1 mmol·L^-1 of SNP for 1 d or 7 d increased the leaf soluble protein content and superoxidase （SOD）,catalase （CAT）,and ascorbic acid peroxidase （APX） activities,and decreased the leaf malondialdehyde （MDA） content significantly,suggesting that exogenous NO could enhance the capacity of cucumber seedlings in scavenging active oxygen species,protect the seedlings from the peroxidation of membrane lipids,and promote the seedlings growth and increase their resistance to high concentration NO-3 stress. After the cucumber seedlings grew in 0.3 mmol·L^-1 of SNP for 7 d,the activities of leaf SOD,POD,and CAT decreased,and the MDA content increased,resulting in the injury of cucumber seedlings. It was indicated that certain concentration （0.1-0.2 mmol·L^-1） exogenous NO could alleviate the NO-3 stress to cucumber seedlings.
出处
《应用生态学报》
CAS
CSCD
北大核心
2009年第12期3009-3014,共6页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(30471187
30871705)
国家自然科学基金青年基金项目(30900983)
山东农业大学中青年创新基金项目(23472)
山东农业大学博士后基金项目(76242)资助
关键词
硝普钠
NO3^-胁迫
黄瓜幼苗
抗氧化酶
生长
sodium nitroprusside NO-3 stress cucumber seedlings antioxidant enzyme growth.
