外源氮素形态及水平对紫花苜蓿幼苗各部位氮含量的影响  

Effects of exogenous nitrogen forms and levels on nitrogen content in different parts of alfalfa seedlings

作　　者：张晓玲[1] 刘晓静[1] 齐鹏[2] 

机构地区：[1]甘肃农业大学草业学院/草业生态系统教育部重点实验室/甘肃省草业工程实验室/中-美草地畜牧业可持续发展研究中心,甘肃兰州730070 [2]甘肃农业大学资源与环境学院,甘肃兰州730070

出　　处：《草原与草坪》2015年第2期9-14,共6页Grassland and Turf

基　　金：国家自然科学基金(31460622);甘肃省财政厅项目"外源氮素供应对紫花苜蓿产量和品质形成影响研究"资助

摘　　要：在完全营养液条件下,采用砂培法,研究了2种氮素形态(NO-3-N,NH+4-N)和5个氮素水平(0、105、210、315、420mg/L)对紫花苜蓿品种"甘农3号"和"陇东苜蓿"幼苗各部位氮含量的影响。结果表明:施氮处理下各部位NO-3-N含量、NH+4-N含量和全氮含量均显著高于CK(P<0.05)。"甘农3号"和"陇东苜蓿"2个品种的各部位氮含量变化一致,均随施氮水平的升高呈先增加后降低的趋势,但峰值表现不一。同一氮素形态及水平下,不同部位NO-3-N、NH+4-N及全氮含量表现为:叶>根>茎。"甘农3号"在NO-3-210处理下叶、茎、根中NO-3-N含量最优,分别为490,385和463μg/g;"陇东苜蓿"分别为473,355和447μg/g。"甘农3号"在NH+4-210处理下叶、茎、根中NH+4-N含量最优,分别为212,182和194μg/g;"陇东苜蓿"茎和根中含量分别为177μg/g、178μg/g,叶却在NH+4-315处理最大,为189μg/g。"甘农3号"在NH+4-315处理下叶、茎、根中全氮含量最优,分别为4.25%,1.7%和3.47%;"陇东苜蓿"叶和根中含量分别为4.01%、3.08%,茎却在NH+4-210处理最大,为2.33%。对于同一部位除"陇东苜蓿"茎全氮含量高于"甘农3号"外,其他部位的NO-3-N、NH+4-N和全氮含量均表现为"甘农3号"优于"陇东苜蓿"。Under the condition of complete nutrient solution,the effect of two kinds of nitrogen forms （ni-trate nitrogen and ammonium nitrogen）and five nitrogen levels （0,105,210,315,420 mg/L）on content of ni-trogen in different parts of Medicago sativa L.cv.Gannong No.3 and Medicago sativa L.cv.Longdong were studied at seedling stage by sand culture method.The results showed that the content of NO3^- -N,the content of NH4^＋ -N and total nitrogen content in different parts of alfalfa under nitrogen treatments were significantly high-er than that of CK（P 〈0.05）.Gannong No.3 and Longdong had same variation of nitrogen content in different parts.The variation showed a trend of increased first and then decreased with the increase of nitrogen level,but the maximum were not the same.Under the same nitrogen form and level,the content of NO3^- -N,the content of NH4^＋ -N and total nitrogen content in different parts of alfalfa showed：leaf 〉 root 〉 stem.Under the best treatment with NO3^- -210 to ‘Gannon No.3’,the content of NO3^- -N in leave,stem,root were 490 μg/g,385 μg/g,463 μg/g,respectively.they were 473 μg/g,355 μg/g,447 μg/g in alfalfa of ‘Longdong’.Under the best treatment with NH4^＋ -210 to ‘Gannon No.3’,the content of NH4^＋ -N in leave,stem,root were 212 μg/g,182 μg/g,1 94 μg/g.The content of NH4^＋ -N in stem and root of ‘Longdong’were 177 μg/g and 178 μg/g,but the best treatment in leaf was NH4^＋ -315,it was 189 μg/g.Besides,under the best treatment with NH4^＋ -315 to ‘Gannon No.3’,the total nitrogen content in leave,stem,root were 4.25%,1.7%,3.47%,repectively.The total nitrogen content in leaf and root of ‘Longdong’were 4.01% and 3.08%,but the best treatment in stem was NH4^＋ -210, it was 2.33%.For the same part,the nitrogen content of ‘Longdong’was higher than ‘Gannon No.3’in stem, but the content of NO3^- -N,NH4^＋ -N and total nitrogen in the other parts of ‘Gannon No.3’were higher than that of ‘Longdong’.

关 键 词：紫花苜蓿 氮素形态 不同部位 氮含量 

分 类 号：S143[农业科学—肥料学] S541[农业科学—农业基础科学]