Characteristics of Tomato Fertilizer requirement

The nutrient uptake of tomato was different in different growth stages, and the nutrient uptake increased with the growth and development of the plant. Nitrogen was mainly absorbed in the seedling stage, and the demand for phosphorus and potassium increased with the thickening and growth of the stem.

At the beginning of the result, nitrogen accounted for 50% of the three main nutrient elements (nitrogen, phosphorus, potassium). Potassium accounts for only 32%. When entering the peak period of fruit and the beginning of harvest, nitrogen accounts for 36% and potassium accounts for 50%. It was analyzed that the ratio of nitrogen, phosphorus and potassium in the whole tomato plant was 1: 0.4 / 2, while the absorption of nitrogen and potassium by tomato was 40% 50% of the amount of fertilizer applied, and the absorption of phosphorus was only about 20% of the amount of fertilizer applied, which was twice as much as that of nitrogen and potassium. Therefore, the proportion of nitrogen, phosphorus and potassium fertilizer application rate of tomato should be 1:1:2. From the experimental results (Table 11-3), it can also be seen that compared with the single application of nitrogen fertilizer, the application of phosphorus and potassium fertilizer has obvious yield-increasing effect.

Deformed fruits often appear in production practice. The appearance of deformed fruit is directly related to the low temperature encountered in tomato flower bud differentiation, but excessive nitrogen fertilizer, prosperous plant growth, especially excessive fertilizer, wet and thick stem growth during seedling growth are also the inducements to produce abnormal fruit. The application of too much nitrogen fertilizer in the growing season will also cause non-viral "curling leaves" in the parietal leaves, which is similar to tomato virus symptoms, but not tomato virus disease. However, due to too much nitrogen fertilizer, it is easy to get infected with virus disease after rolling leaves. In addition, the "navel rot" of fruit in high temperature and drought season is closely related to calcium deficiency.