Field experiments were carried out with different nitrogen application to study the responses of winter wheat in grain yield, nitrogen absorption and utilization, soil inorganic nitrogen accumulation, SPAD value in leaves and canopy vegetation index NDVI value using Hengguan 35 as material under the high-yield system at Qibin District, Hebi City, Henan Province from 2008 to 2010. At the same time, appropriate nitrogen fertilizer application of high-yield winter wheat producted and the feasibility of nitroge...