Influence of applying phosphorus on soil nitrate N and nutrient uptake and yield of summer maize | 施磷对夏玉米土壤硝态氮、吸氮特性及产量的影响

Chinese. 研究不同施磷水平对夏玉米生长期土壤硝态氮时空分布、累积量及玉米籽粒产量的影响，为夏玉米合理施肥提供参考依据。采用田间小区试验, 在施磷水平分别为0，60，120和180 kg/hm2时，研究施磷对夏玉米产量及土壤氮素吸收累积的影响。在0～110 cm土层，随土壤剖面深度的增加，土壤硝态氮含量逐渐降低，0～30 cm土层明显高于30～110 cm土层且变幅较大，施磷肥能显著降低土壤硝态氮含量。随夏玉米生育期推进，0～110 cm土层硝态氮累积量呈先降低后升高的趋势，于灌浆期达到最低值；当施磷水平为120 kg/hm2时，成熟期0～110 cm土层硝态氮累积量低于施磷60和180 kg/hm2的处理；施磷肥能显著增加玉米籽粒产量、籽粒吸氮量及氮收获指数，均以施磷水平为120 kg/hm2时最高。在施氮基础上施用磷肥，有利于提高玉米籽粒产量,促进作物对氮素的吸收累积，减少土壤中硝态氮的累积及向更深土层中的运移量。

English. A field experiment was carried out to study the influence of applying phosphorus (P) fertilizer on soil nitrate N (NO-3-N) distribution and accumulation amounts in soil profile, grain yield of summer maize to provide theoretical direction for applying P fertilizer (APF) to maize. Different levels of P fertilizer were used in maize field, 0, 60, 120, 180 kg/hm2 respectively. Soil nitrate N concentration decreased obviously with the increase of soil depth in 0C110 cm layer, and NO-3-N concentration in 0C30 cm layer had a larger variation range than that did in 30C110 cm layer. Applying N mixed with P decreased the amount of NO-3-N significantly in soil depth. Firstly there was a decrease and then increase on NO-3-N accumulation amounts in 0C110 cm layer following maize growth stages, and it reached lowest in stem elongation stage. NO-3-N accumulation amounts of APF were lower than that of treatment of 60 and 180 kg/hm2 at 120 kg/hm2 during harvest stage in 0C110 cm layer. APF could improve sharply grain yield and amount of N taken by grain and N Harvest Index, which were the highest under the 120 kg/hm2 of PFA treatment. Based on applying N fertilizer, APF can increase yield clearly, and promote N absorption by crops, reduce the NO-3-N accumulation amounts and translocation of NO-3-N in deep soil.