Effect of Different Nitrogen Application Rate and Nitrogen, Phosphorous and Potassium Ratio on the Yield and Quality of Flue-cured Tobacco

In order to get the suitable nitrogen application rate and the ratio of nitrogen and potassium in tobacco area of Chaling,an area comparison test is carried out to compare the different applying of nitrogen and the ratio of different nitrogen and potassium in Fuchong country in Yaopo town.The result showed that: the different amount of nitrogen fertilizer has a significant effect on the growth of flue-cured tobacco;the yield and quality of tobacco are optimum when nitrogen fertilizer is 180 kg/hm2,and the ratio of nitrogen,Phosphorous and Potassium is1∶0.8∶3;the stem,height,good leaf number,leaf waist width,and yield of the tobacco plant rise with the increasing of the nitrogen fertilizer and ratio of nitrogen and potassium;when the nitrogen fertilizer is higher than 180 kg/hm2,and the ratio of nitrogen and potassium is higher than 3,the yield of the flue-cured tobacco,first class and secondary class tobacco’s proportion,and the coordination of intrinsic chemical composition all declined.