The experiment was carried out in the testing farm of Renqiu city of Hebei province. It's mainly including two groups: The first one adopts two factors splitting plot designed to study the effect on the yield and protein components of strong gluten wheat of different nitrogen applications.The second one was designed by the random arrangement of 3 levels and 3 factors in order to study the effect on the yield and protein components of Jimai20 of the different levels of nitrogen, phosphorus and pot...