A Study On The Relationship Between Different Ratio Of Nitrogen And Potassium Fertilizer In Topdressing And Reducing Nitrogen Content And Improving The Quality Of Cured-Upper-Leaf

By using the best regression of two factors of Nitrogen and Potassium fertilizer, studied on the relation between the quality, main chemical components, armor and taste of the upper leaf and the ratio of Nitrogen and Potassium in topdressing period of flue-cured tobacco (K326). The results indicated that the changing trend of the average price was similar to this of the high-class leaf proportion. In the first topdressing process, they both performed the trend of increasing firstly and then declining with increasing the amount of Nitrogen and Potassium fertilizer. The effect of Nitrogen fertilizer to the Nitrogen Compounds such as total Nitrogen, nicotine, protein was more tremendous than this of Potassium fertilizer. They all performed the trend that increased firstly and then declined with increasing the amount of Nitrogen fertilizer. But the effect to reducing sugar and Potassium ion was opposite. The effect of different ratio of Nitrogen and Potassium fertilizer in topdressing to the petroleum ether extract and armor and taste of cured leaf was more tremendous. They both performed the trend that declined firstly and then increased with increasing the amount of Nitrogen fertilizer.So far as to improve the usability of upper leaf, in the first topdressing, the application of Nitrogen fertilizer should be controlled in 13.0～15.0 kg/hm~2 and which of Potassium fertilizer should be 58.6～76.4 kg/hm~2 in order to improve the appearance quality. In order to improve the armor and taste, the application of Nitrogen fertilizer should be controlled in 0～3.0 kg/hm~2 and which of Potassium fertilizer should be 121.5～135.0 kg/hm~2. To improve the Potassium content and reduce the Nitrogen content, the application of Nitrogen fertilizer should be controlled in 27.0～30.0 kg/hm~2 and which of Potassium fertilizer should be 121.5～135.0 kg/hm~2. In order to reducing the nicotine content and improving the quality, the application of Nitrogen fertilizer should be controlled in 0～3.0 kg/hm~2 and which of Potassium fertilizer should be 94.1 kg/hm~2.