以黑龙江省三江平原大豆主栽品种“合丰50”为试验材料,研究不同时期叶面施氮对大豆叶片叶绿素含量及干物质积累的影响。结果表明,在施肥量为N 5.0kg·hm~(-2)条件下,五叶期(V5期)叶面施氮后叶绿素含量SPAD值为56.4,无籽粒干物重为26.4g,始粒期(R5期)叶面施氮后籽粒干物重为25.0g,均高于其它处理。“合丰50”在R5期施肥量为N 5.0kg·hm~(-2)条件下产量最高。 The main soybean variety Hefei 50 in Sanjiang Plain of Heilongjiang Province was used as experimental material to study the effects of leaf nitrogen fertilizer application on chlorophyll content and dry matter accumulation of soybean leaves at different periods. The results showed that under the condition of N 5.0kg · hm -2, the SPAD value of leaf chlorophyll was 56.4 and the dry matter weight of seedless kernel was 26.4g in the leaf stage at five leaf stage (V5) (R5 phase) after the nitrogen fertilizer leaves dry weight of 25.0g, were higher than other treatments. “Hefeng 50 ” had the highest yield under the condition of N 5.0kg · hm -2 fertilization in R5 stage.