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 sheathglume) 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.