氮素形态和弱光胁迫对茶树生长代谢的影响  

Effects of Nitrogen Form and Weak Light Stress on Tea Plant Growth and Metabolism

作　　者：申瑞寒 马立锋[1] 杨向德 方丽[1] SHEN Ruihan;MA Lifeng;YANG Xiangde;FANG Li(Tea Research Institute,Chinese Academy of Agriculture Sciences,Key Laboratory of Tea Biology and Resources Utilization,Ministry of Agriculture,Hangzhou 310008,China;Graduate School of Chinese Academy of Agriculture Sciences,Beijing 100081,China)

机构地区：[1]中国农业科学院茶叶研究所/农业农村部茶树生物学与资源利用重点实验室,浙江杭州310008 [2]中国农业科学院研究生院,北京100081

出　　处：《茶叶科学》2023年第3期349-355,共7页Journal of Tea Science

基　　金：国家自然科学基金(32172634);国家重点研究计划项目(2021YFD1601103);浙江省“三农六方”科技协作项目(2021SNLF032);中国农业科学院基本科研业务费项目(Y2022LM26)。

摘　　要：为解析氮(N)素形态和弱光胁迫对茶树生长代谢的影响,以2年生龙井43扦插苗为试验材料,通过溶液培养分别供给NH_(4)^(+)-N和NO_(3)^(-)-N 2种不同形态N源,以及正常光照和弱光2种光照强度。结果表明:(1)茶苗净光合速率主要受N素形态影响,正常光照条件下,NH_(4)^(+)-N处理明显高于NO_(3)^(-)-N处理;相同氮素条件下,与正常光照相比,弱光胁迫有减弱茶苗净光合速率的趋势。(2)茶苗新梢叶绿素含量主要受氮素形态和光照共同影响,弱光胁迫有助于提高叶绿素含量。正常光照时NH_(4)^(+)-N处理的茶苗新梢叶绿素含量显著高于NO_(3)^(-)-N处理,但叶绿素a(Chl a)和叶绿素b(Chl b)含量的比值(Chl a/b)基本不变,弱光胁迫后新梢叶绿素含量增加,但NH_(4)^(+)-N处理的新梢Chl a/b值明显提高,而NO_(3)^(-)-N处理的Chl a/b值略有下降,茶树施用NO_(3)^(-)-N比施用NH_(4)^(+)-N更具有耐荫性。(3)茶苗N素吸收主要受N素形态和光照共同影响,弱光胁迫有助于提高茶苗新梢N素的累积。正常光照时NH_(4)^(+)-N处理的茶苗新梢N含量要明显高于NO_(3)^(-)-N处理,弱光胁迫明显增加茶树地上部N含量。(4)新梢品质成分变化主要受到光照影响,但酚氨比的变化受光照和氮源的共同作用影响。正常光照下NH_(4)^(+)-N处理新梢游离氨基酸总量和咖啡碱含量明显高于NO_(3)^(-)-N处理,而酚氨比则低于NO_(3)^(-)-N处理。弱光胁迫后新梢中游离氨基酸和咖啡碱含量进一步升高,而茶多酚含量和酚氨比降低,NO_(3)^(-)-N处理新梢中游离氨基酸总量增加速率和茶多酚含量、酚氨比下降速率更快。研究结果为解析其机制提供理论依据。In order to analyze the effects of N form and weak light stress on the tea plant growth and metabolism,the two-year-old cutting seedlings of‘Longjing 43’were taken as experimental materials,and two different forms of N sources (NH_(4)^(+)-N and NO_(3)^(-)-N) and two light intensities (normal light and weak light) were supplied under solution culture.The results show that:(1) the net photosynthetic rate of tea seedlings was mainly affected by the N form under normal light intensity.The net photosynthetic rate of tea seedlings treated with NH_(4)^(+)-N was significantly higher than that treated with NO_(3)^(-)-N.Under the same nitrogen conditions,compared to normal light,weak light stress had a tendency to reduce the net photosynthetic rate of tea seedlings.(2) Under normal light intensity,the chlorophyll content in young shoots treated with NH_(4)^(+)-N was significantly higher than that treated with NO_(3)^(-)-N,but the chlorophyll a (Chl a)/chlorophyll b (Chl b) ratio was basically unchanged.The chlorophyll content increased significantly after weak light stress,but Chl a/b ratio under NH_(4)^(+)-N treatment was significantly increased,while Chl a/b ratio under NO_(3)^(-)-N treatment was slightly decreased.NO_(3)^(-)-N treated tea plants showed better shade tolerance than that treated with NH_(4)^(+)-N.(3) N uptake by tea seedlings was mainly influenced by both N form and light,and weak light stress helped to improve the accumulation of N in new shoots of tea seedlings.The N content of NH_(4)^(+)-N treated tea seedlings was significantly higher than that treated with NO_(3)^(-)-N under normal light.Weak light stress significantly increased the above-ground N content in tea plants.(4) Under normal light intensity,the contents of free amino acids and caffeine in young shoots treated with NH_(4)^(+)-N were significantly higher than those treated with NO_(3)^(-)-N,while the ratio of tea polyphenol to free amino acids was lower.After weak light stress,the contents of free amino acid and caffeine in shoots further

关 键 词：茶树 铵态氮 硝态氮 光照强度 光合作用 品质成分 

分 类 号：S571.1[农业科学—茶叶生产加工]