Abstract:A field experiment was conducted to study the effects of nitrogen application rate on the protein components and processing quality of wheat grain using two high-quality cultivars,Yannong 15(YN15) and Jimai 19(JM19).Four nitrogen application rates,0(CK)、120(LO)、240(MD) and 360(HI) kg/hm2 of N(urea) were used,and field plots were arranged in a randomized complete block design with three replications.Results showed that N fertilization markedly increased both albumin and globulin contents at early period of grain filling,but this response was weakened stepwise afterward.Till the maturity,there was no significant difference in albumin and globulin content under different N levels.N application could significantly increase both gliadin and glutenin,especially the latter,consequently the ratio of glutenin to gliadin content increased.N application could also increased wet gluten content of flour and prolonged dough development time,stability time and breakdown time.Comprehensive analysis indicated that both the content of gliadin and glutenin and the gliadin/glutenin ratio were important factors determining the processing quality of wheat grain,and it could be used as the indexes to evaluate the parents-offspring selection in wheat quality breeding and cultivation techniques in wheat production.