Abstract: To provide the theoretical basis for rational nitrogen application in the high yield region of North Henan Province,the field experiments were carried out during 2011-2013 using Zhoumai 18 and Jimai 22 as materials.Under the condition of corn straw returning,7 nitrogen fertilizer levels were arranged:N₀ (no nitrogen application in whole growth stage),and N₁,N₂,N₃,N₄,N₅ and N₆,of which 0,60,100,140,180 and 210 kg/ha nitrogen were topdressed respectively at jointing stage under the condition of 120 kg/ha nitrogen as basic fertilizer.The dynamic change of nitrogen content in soil and wheat plants,the amount of nitrogen absorption in wheat plants,the nitrogen utilization efficiency in wheat and soil system and the grain yield under different fertilizer treatments were analyzed.The results showed that nitrogen accumulation of wheat plants and grain yield changed as a single peak curve with the increase of topdressing amount.For the treatments N₃ and N₄,nitrogen accumulation in Zhoumai 18 plants was higher,and the grain yields was higher simultaneously,while Jimai 22 showed higher nitrogen accumulation and higher grain yields in N₁ and N₂ treatments. With the adding of nitrogen amount,nitrogen loss in wheat and soil system tended to rise first and then fall.Nitrogen partial factor productivity (NPFP) and nitrogen agronomic efficiency could be improved significantly with straw returning and proper nitrogen fertilizer application,but they tended to be lower with the continuous increase of nitrogen.In consideration of both nitrogen fertilizer efficiency and grain yield,the appropriate nitrogen application of Zhoumai 18 and Jimai 22 was 220-260 kg/ha and 120-180 kg/ha respectively under the condition of straw returning in wheat and corn double cropping area.

Key words: Winter wheat, Straw returning, Nitrogen application rate, Nitrogen content, Yield

CLC Number: 

• S512.1

• S311