氮肥运筹对华北平原限水灌溉冬小麦产量和水氮利用效率的影响

为了解不同氮肥运筹处理对华北平原限水灌溉条件下冬小麦产量、水分和氮素利用效率的影响,在中国农业大学吴桥试验站限水灌溉(播种前灌充足底墒水,春浇拔节水和开花水)条件下,开展了6个不同氮肥运筹处理(157.5 kg N/ha全部做基肥;基肥88.5 kg N/ha 追肥69 kg N/ha;基肥157.5 kg N/ha 追肥69 kg N/ha;基施88.5 kg N/ha 追施138 kg/ha;226.5 kg N/ha全部做基肥;基肥157.5 kg N/ha 追肥138 kg N/ha)的大田试验。结果表明,限水灌溉条件下,不同氮肥运筹处理的冬小麦经济产量和产量构成因素(有效穗数、穗粒数和千粒重)间无显著差异。冬小麦水分利用效率(1.78~1.87 kg/m3)和氮素生理利用效率(39.65~44.42 kg/kgN)随氮肥施用量加大呈下降趋势,而氮肥生产力则随施氮量增加而显著降低。冬小麦氮素转运量及其对籽粒的贡献率(%)均表现为叶片>茎鞘>穗颖。氮肥一次性基施处理的氮素转运量及其对籽粒的贡献率(%)在各氮肥运筹处理中均较高。在华北平原地区,施氮水平在157.5 kg N/ha且一次性基施,是限水灌溉冬小麦高产、高效、简化的适宜施肥方式。

Effect of Nitrogen Fertilizer Applications on Yield,Water and Nitrogen Use Efficiency under Limited Irrigation of Winter Wheat in North China Plain

To understanding the effect on winter wheat yield,water and nitrogen use efficiency of nitrogen fertilizer applications under limited irrigation in north china plain,experiments with 2 water treatments of the sufficient basis soil moisture content and two-irrigation(elongation stage,flowering stage) in spring,and six nitrogen fertilizer applications of N157.5 0(157.5 kg N/ha,all applied as base fertilizer),N88.5 69(88.5 kg N /ha applied as base fertilizer 69 kg N /ha additional fertilizer applied at elongation stage),N157.5 69(157.5 kg N/ha applied as base fertilizer 69 kg N /ha additional fertilizer applied at elongation stage),N88.5 138(88.5 kg N /ha applied as base fertilizer 138Kg N /ha additional fertilizer applied at elongation stage),N226.5 0(226.5 kg N/ha,all applied as base fertilizer)and N157.5 138(157.5 kg N/ha applied as base fertilizer 138 kg N /ha additional fertilizer applied at elongation stage were carried out at Wuqiao experimental station of China Agricultural University.A randomized complete block design was used with three replications with wheat cultivar Shijiazhuang 8.The results indicated that there was no significant difference in grain yield and yield elements of winter wheat between different nitrogen fertilizer applications under limited irrigation.Water use efficiency and nitrogen fertilizer use efficiency have a decrease tendency along with the increase of N application on the basis of 157.5 kgN/ha,and the nitrogen fertilizer productivity significantly decreased with the increase of N applied rates.Nitrogen transport amount and the contribution ratio(%) of nitrogen have the same tendency(leaf >stem and leaf sheath>glume) in winter wheat.The treatment of whole nitrogen applied as base fertilizer relatively has higher value compared with other treatment(base fertilizer plus additional fertilizer applied at elongation stage)under limited irrigation.Therefore,the treatment of 157.5 kgN/ha applied as base fertilizer was a simple,high-yield and high efficiency application way for winter wheat under limited irrigation in north China plain.