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Most of the central and southwestern regions are small and medium-sized arch sheds, and most of the northern regions such as North China are solar greenhouses. The main fertilization problems are as follows: First, excessive fertilization is common, nitrogen and phosphorus fertilizers are used at a high level, and soil nitrogen and phosphorus nutrients are accumulated. Second, the proportion of nutrient input is unreasonable, and there are obstacles in the supply of elements such as calcium, magnesium and boron in non-calcium soil. Third, excessive irrigation leads to serious nutrient losses. Fourth, continuous cropping obstacles lead to serious deterioration of soil quality, decreased nutrient absorption efficiency, and decreased vegetable quality.
2. Fertilization principle
(1) Rational application of organic fertilizer, reduction of the amount of nitrogen and phosphorus fertilizer, increase of potassium fertilizer, non-calcium soil and acid soil need to supplement calcium, magnesium, boron and other trace elements.
(2) According to crop yield, sorghum and soil fertility conditions, rational allocation of chemical fertilizers, most of the phosphorus fertilizer application, nitrogen and potassium fertilizers; early spring growth should not be frequent top dressing, pay attention to post-flowering and late-stage topdressing.
(3) Combine with high-yield cultivation techniques and adopt the principle of “small number of times†to rationally fertilize.
(4) The old shed with soil degradation needs to return to the field or apply high organic fertilizer with high C/N ratio, reduce the amount of fertilized manure, increase the number of rotations, and achieve the purpose of desalting and reducing continuous cropping obstacles.
3. Fertilization amount and proportion
(1) The seedling fertilizer is added with decomposed organic fertilizer, supplemented with phosphate fertilizer, 60~100 kg of decomposed poultry manure per 0.5 m2 seedbed, 0.5~1 kg of calcium magnesium phosphate fertilizer, 0.5 kg of potassium sulfate, sprayed according to the seedling condition 0.5 %~0.1% urea solution 1~2 times.
(2) Applying high-quality organic fertilizer to the base fertilizer for 2~3 square meters/mu.
(3) The production level is 4000~6000 kg/mu: nitrogen fertilizer (N) 15~20 kg/mu, phosphate fertilizer (P2O5) 8~10 kg/mu, potash fertilizer (K2O) 20~25 kg/mu; production level 6000~8000 Kg/mu: nitrogen fertilizer (N) 20~30 kg/mu, phosphate fertilizer (P2O5) 10~15 kg/mu, potash fertilizer (K2O) 30~35 kg/mu; production level 8000~10000 kg/mu: nitrogen fertilizer (N) 30~38 kg/mu, phosphate fertilizer (P2O5) 15~20 kg/mu, potash fertilizer (K2O) 35~40 kg/mu.
More than 70% of the phosphate fertilizer is used as the base fertilizer (point), and the rest is applied with the compound fertilizer, 20%~30% of the nitrogen and potassium fertilizer base, 70%~80% after the flowering to the ear expansion period, 3~10 times with the water. Shi, each time the application of nitrogen fertilizer (N) does not exceed 5-7 kg / mu.
(4) When the soil pH of the vegetable field is less than 6, the calcium, magnesium and boron are easily deficient, and the calcium fertilizer (Ca) is 50-75 kg/mu, and the magnesium fertilizer (Mg) is 4-6 kg/mu. 2 to 3 times of 0.1% concentration of boron fertilizer.
Facility tomato fertilization technology
1. Major problem
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