控释尿素对云南旱地玉米产量和氮肥利用率的影响
Effects of controlled-release urea on yield and nitrogen utilization rate of maize in arid area of Yunnan

【目的】研究控释尿素对云南旱区玉米产量和氮肥利用率的影响，为该地区玉米生产中氮肥的合理施用提供科学依据。【方法】2011-2012年，在云南省玉米主产旱区采用田间试验，以不施用氮肥为对照（CK），研究单独施用100%，75%，50%控释尿素（CU）和普通尿素(U)，普通尿素分批施用，以及普通尿素与控释尿素共同施用对玉米产量、农艺性状和氮肥利用率的影响。【结果】不同施肥处理对收获期玉米农艺性状的影响有差异，2年试验中均以CK玉米的农艺性状最差；2011年单独施用100%控释尿素处理（CU100%）和40%普通尿素+60%控释尿素作基肥共同施用处理（U40%+CU60%）玉米的农艺性状较优，2012年单独施用100%控释尿素（CU100%）和75%控释尿素处理（CU75%）以及U40%+CU60%处理玉米的农艺性状较优。2011年，CU100%处理玉米产量最高，CK产量最低；2012年，CU75%处理玉米产量最高，其次为CU100%和U40%+CU60%处理，CK产量最低。当氮肥用量相同时，所有CU处理的氮肥利用率均高于U处理。一次性施用普通尿素处理的氮肥利用率为22.2%～33.5%，一次性施用控释尿素的氮肥利用率为32.7%～46.5%，高于一次性施用普通尿素处理。当氮肥用量相同时，所有CU处理的氮肥农学利用率均高于U处理。一次性施用U的处理中，氮肥农学利用率为3.1～8.6 kg/kg；一次性施用CU处理的氮肥农学利用率为7.7～12.7 kg/kg，均高于一次性施用U的处理。普通尿素和控释尿素共同施用处理的玉米产量、农艺性状和氮肥利用率均高于普通尿素处理。分批施用普通尿素处理的玉米产量和氮肥利用率低于控释尿素处理或普通尿素与控释尿素共同施用的处理。【结论】云南旱区玉米种植中，施用比常规施肥氮用量少的控释肥可提高玉米产量和肥料利用率，在研究地内，氮用量为105.0～157.5 kg/hm2的控释尿素处理较佳。
【Objective】Effects of the application of controlled-release urea (CU) on yield and N (nitrogen) use efficiency of maize were studied in the arid area of Yunnan,in order to provide scientific basis for the optimal application of N fertilizer.【Method】The field experiments were conducted in the major maize-growing area of Yunnan from 2011 to 2012 to investigate the effects of CU and common urea (U) on yield,agronomic traits,and N use efficiency of maize.Treatments included CK (with no application of N),U100%,CU100%,U75%,CU75%,U50%,CU50%,U40%B+U60%T (U40% for base fertilizer and surplus U60% for top dressing),and U40%+CU60% (U40% and CU60% for base fertilizer).【Result】The agronomic traits had significant difference among treatments,with the worst traits in CK during the 2-year test period.In 2011,CU100% and U40%+CU60% had better traits.In 2012,CU100%,CU75% and U40%+CU60% had better traits.In 2011,CU100% had the highest yield and CK had the lowest yield.In 2012,CU75% had the highest yield followed by CU100% and U40%+CU60%,while CK had the lowest yield.When the same amounts of nitrogen were applied,all the treatments with CU had higher N use efficiency than those with U.The N use efficiency of the one application of U was 22.2%-33.5% and that of the one application of CU was 32.7%-46.5%.When the same amounts of nitrogen were applied,all the treatments with CU had higher agronomic N use efficiency than those with U.The agronomic N use efficiency of one application of U was 3.1-8.6 kg/kg and that of one application of CU was 7.7-12.7 kg/kg.Yield,agronomic traits and nitrogen use efficiency of maize with U40%+CU60% were all higher than those with U.Yield and nitrogen use efficiency of maize with U40%B+U60%T were lower than those with CU or