Influence of different N,P and K fertilizer rates based on "3415" design on the chemical components in tobacco

Through the field experiment and indoor chemical analysis,the influence of different N,P, K fertilizer rates on nitrogen,potassium,calcium,magnesium,total sugar,reducing sugar and starch content in tobacco was researched. The results showed that when the P2 O5 varied from 0 to 112. 5 kg· ha -1 ,phosphorus had no obvious effect on the absorption of calcium,when the application of P2 O5 was over 112. 5 kg·ha -1 ,phosphorus could inhibit tobacco absorption of calcium elements. When the K2 O varied from 0 to 270 kg·ha -1 ,potassium could promote the accumulation of nitrogen element in tobacco leaf,but when the application of K2 O was over 270 kg·ha -1 ,Potassium would restrain the nitrogen element accumulation. As the nitrogen fertilizer varied from 0 ～ 112. 5 kg·ha -1 ,nitrogen had no obvious effect on the accumulation of total sugar and reducing sugar,when the application of nitrogen was over 112. 5 kg·ha -1 ,nitrogen would reduce the total sugar and reducing sugar accumulation. So it can be concluded that nitrogen fertilizer has obvious effect on the accumulation nitrogen,potassium and calcium content of tobacco leaf,and P and K have different functions in different fertilization range. Nitrogen has obvious effect on the accumulation of sugar in leaves,and the application of P and K fertilizers has obvious effect on the accumulation of carbohydrates.