In order to clarify the effects of interaction between water and nitrogen on nitrogen utilization efficiency and economic yield of spring wheat in dryland region,the total nitrogen content in stalks,leaves,ears without grains and grains of spring wheat during key growth periods as well as economic yield were studied by pot-culture method.The results showed that the total nitrogen content in stalks,leaves and ears without grains of spring wheat was generally decreased with the growth process under the circum...