Effects Of Types And Application Rate Of Nitrogen Fertilizer On The Growth And Quality Of Flue-cured Tobacco

In order to explore the effect of different nitrogen forms ratio and the amount of nitrogen fertilizer on the growth, development and quality of flue-cured tobacco variety K326,field experiment was conducted on Qiubei County of Yunnan province. Through the analysis on the variation of tobacco plant agronomic traits, physiological indicators and the chemical constituents of flue-cured tobacco, we can draw conclusions as follows:1 Effects of different nitrogen forms ratio on growth and development and nitrogen use efficiency of flue-cured tobaccoThe results showed that,there was significant difference among the treatments and contrast after transplanted 60 days on,besides, the T3 (50%nitrate nitrogen and 50% ammonium nitrogen) treatment showed best in the aspect of index of plant agronomic traits. In the aspect of tobacco’s physiological activity, as time goes on the physiological properties performance for first increased and then decreased subsequently, and the ammonium nitrogen and nitrate nitrogen at the same ratio of fertilizer maybe can improve tobacco root absorption capacity and carbon and nitrogen metabolism.Over-ground part biomass and nitrogen content of flue-cured tobacco was mainly accumulated in leaves, there was smaller in stems. And the effect of nitrogen forms on nitrogen use efficiency was more sensitive to biomass and nitrogen content.2 The effect of different nitrogen forms on the chemical quality of flue-cured tobacco leavesDifferent nitrogen forms of flue-cured tobacco leaves total nitrogen, nicotine in tobacco, protein content showed opposite to two sugar content, and the nitrate nitrogen was advantage to carbon catabolite accumulation, the ammonium nitrogen was more conducive to the accumulation of metabolic products. Comprehensive the chemical index 50% ammonium nitrogen +50%nitrate nitrogen more coordination on chemical composition, more in line with the quality of tobacco production standards.3 Effects of nitrogen fertilizer on growth and development and nitrogen use efficiency of flue-cured tobaccoThe experiments results showed that, the plant agronomic traits, activity of physiological properties, the over-ground part biomass and nitrogen content increased with the amount of nitrogen increased. But nitrogen use efficiency decreased with the amount of nitrogen increased, and there was significant difference among all the treatments. Comprehensive all of the indexes, conventional nitrogen fertilizer is the best for tobacco’s growth and development.4 The effect of nitrogen fertilizer on the chemical quality of flue-cured tobacco leavesThe flue-cured tobacco’s total sugar and reducing sugar content decreased with the amount of nitrogen increased. But the total nitrogen, nicotine in tobacco, protein content increased with the amount of nitrogen increased. The flue-cured tobacco leaves’ Total sugar/Nicotine decreased with the amount of nitrogen increased. The highest content of potassium was T3.