文冠果新梢发育过程中不同部位矿质元素的变化特性

为探明文冠果Xanthoceras sorbifolia新梢发育过程中矿质元素的变化特性，找出新梢发育过程中影响各部位发育的关键营养元素，以文冠果为研究对象，通过连续流动分析仪和原子吸收仪测定了新梢生长发育过程中不同部位矿质元素（氮、磷、钾、铁、锰、铜、锌、钙、镁、钠）的质量分数，明确各元素在文冠果新梢内不同部位的分布规律与年动态变化趋势。结果显示:①文冠果新梢发育过程中不同部位氮、磷、钾、铜、铁、锌等质量分数下降，而钙、镁、锰、钠等质量分数则上升。②茎尖矿质元素质量分数接近于幼嫩叶片，并始终高于幼嫩叶片。③除了5月7日外，各时期叶片中的氮、磷、铁、锰等质量分数均高于茎段；各时期内茎尖、茎段、叶片中的钠质量分数差异均不显著。④在新梢生长初期叶片中的镁、锌、铜等质量分数高于茎段，生长后期叶片低于茎段；在新梢生长初期茎段中钾、钙元素质量分数高于叶片，生长后期茎段低于叶片。⑤因子分析结果显示:磷、氮、钾、铜、铁等质量分数对文冠果新梢的发育有重要影响；其中磷、氮、铜是影响茎尖发育的主要矿质元素，磷、氮、钾是影响茎段发育的主要矿质元素，磷、铜是影响叶片发育的主要矿质元素。⑥相关分析表明:氮、磷、钾、铜、锌这5种矿质营养元素之间的吸收与积累呈显著正相关（P < 0.05），而钙、镁、锰、钠等元素与氮、磷、钾、铜、锌等元素呈显著负相关（P < 0.05）。磷、氮、钾、铜、铁等对文冠果新梢的发育有着重要影响，在施肥时应该注意补充磷、氮、钾、铜、铁等影响较大的矿质元素。同时合理搭配其他必需的矿质元素，注意用量的协调，保证文冠果树体营养均衡、植株健康，使文冠果树施肥达到合理化和规范化。

Mineral elements for new shoot development in Xanthoceras sorbifolia new shoots

To clarify the variable characteristics of mineral elements in the development of Xanthoceras sorbifolia shoots, key nutrient elements influencing the development of various parts were used. Mineral elements (N, P, K, Fe, Mn, Cu, Zn, Ca, Mg, and Na) in different parts of the shoots were measured using Autoanalyzer and atomic absorption spectrometers with new shoots of X. sorbifolia from different growth periods. Distribution regularities and dynamic change trendencies of different mineral elements in different parts of the new shoots of X. sorbifolia were then clarified using a factor analysis and correlation analysis. Results showed that:(1) N, P, K, Cu, Fe, and Zn in the shoots decreased during shoots development, and Ca, Mg, Na, and Mn in the shoots increased. (2) Mineral elements in stem tips close to young leaves was always higher than young leaves. (3) Except on May 7th, N, P, Fe, and Mn in leaves were higher than stems. No significant differences were found for Na among stem tips, stems, and leaves. (4) Contents of Mg, Zn, and Cu in leaves at the early stage of shoot growth were higher than in stems, but at the later growing stage were lower. At the early stage, K and Ca content in stems were higher than in leaves, and at the later stage were lower than in leaves. (5) The factor analysis showed that the contents of P, N, K, Cu, and Fe had important effects on the development of X. sorbifolia shoots. The main mineral elements affecting stem tip development were P, N, and Cu; affecting stem development were P, N, and K; and affecting leaf development were P and Cu. (6) The correlation analysis for uptake and accumlation of mineral elements showed significant positive correlations of N, P, K, Cu, and Zn (P < 0.05); whileas, Ca, Mg, Mn, and Na had significant negative correlations (P < 0.05). Also, P, N, K, Cu, and Fe had an important effect on the development of X. sorbifolia shoots. To ensure a nutritional balance and plant health, additions of P, N, K, Cu, Fe and other necessary mineral elements should be coordinated and reasonably applied as fertilizer, to achieve a rational and standardized fertilization program for X. sorbifolia.