氮素营养对园林植物根系生长与生理特性影响的研究

Study on the Influence of Nitrogen Nutrition on Garden Plants' Root Growth and Physiological Properties

以落叶松、橡胶树等园林植物和大田作物为基础,阐述了园林植物根系在氮素营养条件下发生的一系列形态与生理变化。在一定施氮浓度下,随着施氮浓度的增加,园林植物根鲜重、干重逐渐增加,根系总表面积、侧根数、根冠比增大,根系变细变长;不同施氮时期的影响也较为显著,其中早施氮肥对根系生长有利;对根系而言,硝态氮效应比其他形态的氮素效果好;同时,一定的施氮量可以明显增加根系吸水量和根系活力,增加根系分泌物质量,促进碳氮代谢,减少根系内游离氨基酸的数量,维持根系内氮素代谢的平衡。

Based on larch, rubber tree and other garden plants and field crops, this paper describes a series of morphological and physiological changes of the root system of garden plants under the nitrogen nutrition conditions. In a certain nitrogen concentration, as nitrogen concentration increases, the fresh weight and dry weight of garden plants＇ roots gradually increase, the total root surface area, lateral root number, root/shoot ratio increase, too, and the roots get longer and thinner; the influence of different periods of nitrogen application is more obvious, the early application of nitrogen fertilizer is beneficial to root growth; the nitric nitrogen effect is better than that of other forms of nitrogen for the roots; at the same time, a certain amount of nitrogen can significantly increase the water absorbing capacity and activity of the roots, increase the quality of secretory materials of the roots, promote carbon and nitrogen metabolism, reduce the number of free amino acids within the roots to maintain the balance of nitrogen metabolism in roots.