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利用~(15)N示踪技术在温室中研究了无渗漏（长期淹水）和渗漏条件下氮肥施用量对水稻生长和氮肥利用率的影响。氮肥对水稻地上部和根的生长起重要作用。水稻不同生育阶段各器官干物质积累随施肥量增加而提高。土壤的渗漏状况也强烈影响水稻各部分的生长及氮肥利用率。长期淹水条件下，水稻的根系生长受到抑制，地上部积累量下降，氮肥利用率为18．66％～35．67％；在渗漏条件下，水稻的生长状况相对较好，氮肥利用率达42．0％～65．8％。水稻对氮肥的利用率随氮肥用量的增加而减少，作为基肥施用~(15)N回收率比追施低。长期淹水条件下氮肥的激发效应为18％，高于渗漏条件下的5．1％。0～80cm土壤剖面中残留的肥料氮低于总施用量的10％。
The effects of nitrogen application rates on rice growth and nitrogen use efficiency under non-seepage (prolonged flooding) and seepage conditions were studied in greenhouse using ~ (15) N tracer technique. Nitrogen fertilizer plays an important role in the growth of rice shoots and roots. The dry matter accumulation of various organs at different stages of rice increased with the increase of fertilizer application. Soil leakage also strongly affected the growth and nitrogen use efficiency of various parts of rice. Under long-term flooding, the root growth of rice was inhibited and the accumulation of above-ground parts decreased, and the utilization rate of nitrogen fertilizer was 18.66% -35.67%. Under the condition of seepage, the growth of rice was relatively good. The nitrogen use efficiency Up to 42.0% ~ 65.8%. The nitrogen use efficiency of rice decreased with the increase of N application rate, and the recoveries of ~ (15) N as basal fertilizer were lower than those of topdressing. Under long-term flooding conditions, the stimulating effect of nitrogen fertilizer was 18%, higher than the 5.1% under the leakage condition. The residual nitrogen in 0-80 cm soil profiles is less than 10% of the total application.