氮素形态和氮水平对烟草氮、磷、钾、氯积累分配的影响

Effect of Nitrogen Form and Concentration on Distribution of Nitrogen,Phosphorus,Potassium and Chlorine in Different Organs of Tobacco

为了解不同氮素形态和氮水平对烟草吸收矿质元素的影响,开展了营养液栽培试验。结果表明:纯硝态氮供应的叶片氮、磷含量随氮质量浓度增加而降低;有铵参与供氮的叶片氮、磷含量随氮质量浓度的增加而增加;叶片钾含量随总氮供应变化的规律不同于氮、磷,其在铵硝比5∶5之前随氮质量浓度的增加而降低,在铵硝比达到7∶3之后随氮质量浓度增加而增加,以铵硝比0∶10并氮质量浓度35 mg/L时取得叶片最高钾含量(6.32%),在铵硝比10∶0并氮质量浓度为35 mg/L时取得最低钾含量(3.19%);叶片氯含量有随铵硝比增大而提高的趋势。随铵硝比增加,叶片氮、磷、钾、氯和茎中氮、磷、钾积累量降低,铵硝比相同时,随氮质量浓度增加,钾积累量增加,叶片钾积累量在铵硝比0∶10并氮质量浓度140 mg/L时取得最高积累量1 543.57 mg/株;根氮、磷积累量在铵硝比7∶3及以下,随氮质量浓度增加而增加,根钾积累量随供氮改变没有明显变化规律。叶片中氮、磷、钾含量和积累量均高于茎、根中氮、磷、钾含量和积累量。研究认为:铵态氮有利于叶片磷、氯积累,不利于叶片钾积累;硝态氮有利于叶片钾积累,不利于叶片磷、氯积累,在较高氮质量浓度下不利于叶片氮积累。

For understanding the effect of two forms of nitrogen（N） and nitrogen concentration on absorption of main mineral elements by different organs in tobacco,outdoor hydroponics were carried out.The conclusions were as follows.In leafs,N and phosphorus（P） content increased with N concentration decreasing at only nitrate-N,and increased with both ammonium and nitrate supplement.The trend of potassium（K） content changing with N were different with N and P.The content of K decreased with N rising below the ratio of 5∶5,and achieved the highest content of 6.32% at 0∶10 of ammonium/nitrate ratio simultaneously at 35mg/L of N,the lowest K content of 3.19% was achieved at ratio of 10∶0 and 35mg/L.whereas increased with N at ratio of 7∶3 and after that.The chlorine（Cl） content had a trend of increase with ratio of NH4＋/NO3-rising,its accumulation increased with N level rising at the same NH4＋/NO3-.The amount of accumulation of N,P,K and Cl in leaf,and N,P,K in stem,decreased with the rising of ratio of NH4＋/NO3-.K accumulation attained the highest amount of 1543.57mg per individual plant at ratio of 0∶10 and 140mg/L N simultaneously.The content of N,P and K in leaf were higher then that of stem and root.In this experiments,it was sure that ammonium-N enhenced the P,Cl accumulation and inhibited K accumulation in leaf;on the contrary,Nitrate increased K accumulation and decreased P,Cl accumulation in leaf,and made N accumulation decreased in high N level.Lower ratio of ammonium to nitrate and lower level of nitrate-N was in favor of K content in leaf.