干旱胁迫下氮素对小麦幼苗生理特性的影响  

Effect of Nitrogen on Physiological Characteristics of Wheat Seedlings Under Drought Stress

作　　者：吴秀宁[1] 刘英 刘平 王新军[1] 赵永平[1] WU Xiuning;LIU Ying;LIU Ping;WANG Xinjun;ZHAO Yongping(Shangluo University,Shangluo,Shaanxi,726000;Ningqiang No.2 Middle School,Hanzhong,Shaanxi 724400,China)

机构地区：[1]商洛学院,陕西商洛726000 [2]宁强县第二中学,陕西汉中724400

出　　处：《贵州农业科学》2019年第7期1-4,共4页Guizhou Agricultural Sciences

基　　金：商洛市科技创新团队项目“秦岭特色药用植物次生代谢与抚育开发创新团队”（SK2017-45）

摘　　要：为干旱地区小麦合理施氮提供依据,以小麦品种商麦5226和小偃15为材料,设置低氮、中氮和高氮3个氮素水平,PEG-6000模拟干旱处理(严重干旱、中度干旱及正常水分3个水平),测定不同水氮耦合处理下小麦叶片抗氧化酶活性、质膜氧化程度和渗透调节物质变化。结果表明:1)小麦叶片POD活性、CAT活性、可溶性糖含量和脯氨酸含量在中度干旱和严重干旱下均表现为高氮>中氮>低氮;2)在中度干旱下,小麦叶片SOD活性和可溶性蛋白含量表现为高氮>中氮>低氮,MDA含量和相对电导率表现为低氮>中氮>高氮;3)在重度干旱下,小麦叶片SOD活性表现为中氮>高氮>低氮,MDA含量、相对电导率和可溶性蛋白含量变化趋势因品种而异。干旱胁迫环境下适度氮素营养可提高小麦叶片的保护酶活性、降低质膜氧化程度、增加渗透调节物质,从而增强小麦的苗期抗旱性。The effects of different water and nitrogen coupling treatments(three nitrogen levels and three drought stresses)on leaf antioxidant enzyme activity,plasma membrane oxidation degree and osmotic adjustment substance content of Shangmai 5226 and Xiaoyan 15(two wheat varieties)were studied to provide the scientific basis for rational fertilization of wheat in drought region.Result:1)Leaf POD activity,CAT activity,soluble sugar content and proline content of wheat are high nitrogen>medium nitrogen>low nitrogen under medium and severe drought stress.2)Leaf SOD activity and protein content of wheat are high nitrogen>medium nitrogen>low nitrogen under medium drought stress.Leaf MDA content and relative conductance are low nitrogen>medium nitrogen>high nitrogen under medium drought stress.3)Leaf SOD activity of wheat is medium nitrogen>high nitrogen>low nitrogen under severe drought stress.Leaf MDA content,relative conductance and soluble protein content vary with wheat varieties under severe drought stress.The suitable nitrogen nutrition can improve leaf protective enzyme activity,reduce leaf plasma membrane oxidation degree and increase leaf osmotic adjustment substance content in wheat under drought stress,which improves drought resistance of wheat seedlings.

关 键 词：小麦幼苗 干旱胁迫 氮素水平 生理特性 

分 类 号：S512.1[农业科学—作物学]