【作者】 杜旭华；

【导师】 彭方仁；

【作者基本信息】 南京林业大学 ， 森林培育， 2009， 博士

【摘要】 氮素形态影响植物生长生理研究是栽培学的重要基础研究内容。本文研究了不同形态氮素配比施肥对茶树个体生长、有效化学成分、主要矿质元素、氮代谢和光合生理的影响;探讨了茶树喜铵的生理生化基础。主要结论如下:1.氮素形态对茶树高生长和持嫩性影响显著,对粗生长影响相对较小。增加铵态氮会提高茶树叶片Pn、Gs、Tr和GS活性,过高则明显降低光合能力和GS活性,对GOGAT影响较小;多数处理的Pn日变化呈双峰型,纯硝和硝铵比7:3呈单峰型;各处理的酶活性年动态相似。2.不同处理根系St、Sa、氮素吸收效率以及根系吸收动力学主要参数差异显著,氮素运转效率、比面积和Sa/St差异小;硝铵比5:5的氮素吸收较优。氮素形态对茶树全氮含量影响很大,高铵比例明显较低;对全磷和全钾影响不显著。3.铵态氮比例的增加会降低茶多酚含量、增加游离氨基酸和咖啡碱含量,硝铵比7:3和5:5处理时均较高,高铵比例时大幅下降;处理间年动态变化较一致;酚氨比差别小。4.氮素形态影响茶树生长生理表现在适中硝铵比施肥会大幅改变茶树根系对无机氮的吸收动力学特性和叶片氮素代谢,改善茶树根系活力,明显改变叶片的全氮含量,提高光合能力,改善个体生长和春稍持嫩性,优化春芽主要成分组成。高铵比例明显不利于生长。更多还原

【Abstract】 It was a hot focus that the effect of different forms nitrogen application on the growth physiology. The effect of nitrogen form on growth of plant spring shoots, main chemical components, content of mineral elements, nitrogen metabolism and photosynthetic physiology were studied in plot experiment, with four different tea varieties. The physiology and biochemical bases for the reason that tea prefers to using ammonium was discussed. The main results were concluded as follows:1. The height growth of tea plant and time of keeping tenderness were greatly affected by nitrogen form, comparing the little effect on girth growth. The photosynthetic capacity, such as Pn, Gs and Tr, and GS activity were enhanced when the proportion of ammonium nitrogen was high. But when the ammonium proportion was higher than 70%, the capacity and GS activity reduced obviously.The diurnal variations of Pn with pure nitrate and NO3--N:NH4+-N7:3 application were one peak type, and others were double peaks. The annual dynamic of GS and GOGAT activity with different treatment were similarly.2. The total absorption area (St), active absorption area (Sa), the kinetics of ammonium and nitrate uptake in root and efficiency of nitrogen usage were affected by nitrogen form significantly, comparing the effect on ratio of Sa/St, specific surface area, and nitrogen transportation ratio was small. And the comprensive ability of nitrogen absorbing and utilization was relatively better with NO3--N:NH4+ -N5:5 application. The effect of nitrogen form on total nitrogen (TN) was significant. And the effect on TP and TK was relatively small.3. The increment of ammonium nitrogen in plot experiment will lead to the increasing of free amino acids and caffeine content, and the decrement of tea polyphenol content. These contents were high under the NO3--N:NH4+-N7:3 or 5:5 treating. But the contents were low when the proportion of NH4+-N exceeding 70%. The annual dynamic of chemical components was similar among different treatments. And the tea polyphenol/free amino acids had small difference.4. The effect of nitrogen form on physiological mechanism of tea grow manifested at the comprehensive influence on tea plant. When the NH4+-N proportion was increasing, the kinetics of ammonium and nitrate uptake was changed greatly. The root activity was promoted. The activity of key enzymes in ammonium assimilation progress in leaves were affected, especially the GS activity was affected larger than GOGAT activity. TN in leaves was also changed greatly with nitrogen form treating. Both the enzymes and the mineral content in leave, with the moderating mixed nitrogen application, were all better than pure nitrogen using. And the photosynthetic capacity was promoted greatly when the ratio of different nitrogen was suitable. Then, the individual and spring shoot growth was improved. But when the proportion of ammonium was too high, the growth and physiology of these plants was not very googd. These effects on tea plant might be related to the NO3- played as a signal role to regulating these physiological mechanisms.更多还原