The Effect Of Different Nitrogen (N) And Potassium (K) Levels In Base Fertilization On The Yield And Quality Of Tomato In Greenhouse

This experiment took Jing Peng Yi Hao Tomato as materials and studied the yield as well as quality characters of tomato in Yang Zhou area under different Nitrogen (N) and Potassium(K) fertilization levels separately. This experiment observed the main yield and quality characters of tomato including the height of the plant, the stem diameter, the chlorophyll content, the leaf numbers and the yield characters as well as the content of Vitamin C, the soluble sugar, the titrable acid, the soluble solid, the nitrate content and the content of K⁺, Ca²⁺, Mg²⁺.The results indicated:1. N75 was the best Nitrogen (N) fertilization level among 7 different levels in the facet of the height of the plant, the stem diameter, while the content of Potassium (K) fertilization and Phosphor (P) fertilization had been fixed. N75 played well in terms of the fruit numbers and average single fruit weight of the third spike; the maximum yield of per plant had been reached under the level of N75, which had no significant difference with N50. In the experiment, N50 had the best performance on early yield of per plant, average single fruit weight and the content of Vitamin C, the soluble sugar, the soluble solid of tomato as well as the soluble sugar to titrable acid ratio, which reached the significant difference compared with other levels. As the Nitrogen (N) fertilization level went up in the subsoil, the titrable acid content droped first with the bottom at N50 then rised quickly and the nitrate content went up directly. The content of K+ had no significant difference under 7 levels while the content of Ca²⁺ and Mg²⁺ had differences under some levels without any visible trend. Generally, given the better performance on main yield and quality characters of tomato, N50 (carbamide content: 8.33kg/667m2) was the ideal Nitrogen (N) fertilization level in the experiment area of Yang Zhou.2. K150 was the best Potassium (K) level in the facet of improving the yield and the quality as well as the flavor and nutritional value of Jin peng yi hao while the content of Nitrogen (N) fertilizer and Phosphor (P) fertilizer had been fixed. K150 had the most significant difference from other 3 Potassium (K) fertilization levels in the yield and quality characters and had best results in height of the plant, the stem diameter as well as the content of Vitamin C, the soluble sugar, the soluble solid and the soluble sugar to titrable acid ratio. The titrable acid, the nitrate content and the Ca²⁺ content droped with the bottom at K150 as the Potassium (K) fertilization level went up in the subsoil, while the Mg²⁺ had the contrary trend. The K+ content had no significant difference under each levels. As a conclusion, K150(KCl content: 12.52kg/667m2)was the best Potassium(K) fertilization level to get the tomatoes with high yield and better quality in experiment area of Yangzhou.3. The results above indicated that 50% reduction or the Nitrogen (N) fertilization level could also reach the goal of ensuring spring-cultivated tomatoes in greenhouse with high yield and better quality. Increasing the content of Potassium (K) fertilization helped to improve the yield and quality of tomatoes given the insufficient use in production at present. Further studies were required to find ideal Potassium (K) fertilization level.