基于15N示踪的施肥量与氮素含量变化规律的研究

【研究目的】本文研究水稻叶片全氮含量、15N丰度的变化以及与施氮水平之间的关系；【方法】以临稻11，圣稻13和阳光200三个水稻品种为材料，进行盆栽实验；【结果】结果表明，不同生育期水稻叶片全氮含量和15N丰度均随施氮水平逐渐增加。顶1叶片全氮含量和施肥量仅在拔节期极显著相关性，但是3个叶位15N丰度在全生育期与施氮量均达到0.01水平极显著相关。三个水稻品种不同叶位全氮含量随着施氮水平的提高总体呈现增加趋势；15N示踪表明拔节期低氮素水平下位叶片15N丰度较上位高；在高氮素水平上位叶片15N丰度增加；孕穗期上位叶的氮素大量转移到穗部，导致孕穗期上位叶的15N丰度明显小于下叶位；抽穗期和灌浆期由于氮素营养的运转，下叶位15N丰度明显小于上叶位。【结论】叶片15N丰度的变化更能反映出肥料供应的差异状况。和叶片全氮含量比较，叶片15N丰度与施氮肥量的相关性更能说明施氮肥量和叶片氮素营养的关系。

The Varieties between the Fertilizer and Rice Leaf Nitrogen Concentration Based On ~(15)N Tracer

Based on the ~(15)N tracer method,a series of greenhouse potted experiments were conducted with three rice cultivars(Lindao11,Shengdao13 and Yangguang200) to investigate the relationships between rates of fertilization and leaf nitrogen concentration(including ~(15)N abundance and total nitrogen).The results showed that leaf nitrogen concentration and ~(15)N abundance were sensitive to increased nitrogen supply.The relationships between leaf nitrogen concentrations and the rates of fertilization indicated t...