Effect of Nitrogen Fertilizer Rate on Quality of Greenhouse Cucumber

[Objective] The aim of the research was to study the effect of nitrogen fertilizer rate on quality of greenhouse cucumber.[Method] The change of the content of Vc,polysaccharide and nitrate in cucumber were studied with greenhouse cucumber in Dengzhuang town,Hengshui city,Hebei province as tested materials.[Result] When nitrogen fertilizer rate was lower than 225 kg/hm2,the contents of Vc and polysaccharide in cucumber were increased with increasing the nitrogen fertilizer rate,and they reached the highest when it was 225 kg/hm2,but they were reduced by applying excessive use of nitrogenous fertilizers.The nitrate content was positively correlated with nitrogen fertilizer rate,and the optimum regression equation was Y=1.502X+24.407(R2=0.979 2).The nitrate content in all of the samples was lower than that of in national standard.[Conclusion] The optimum nitrogen fertilizer rate was 225 kg/hm2 in this research.More or less were bad for yield and quality of cucumber.