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First, the principle of fertilization. The so-called broccoli formula fertilization technology is a fertilization technique that is scientifically quantified by traditional empirical fertilization methods in broccoli cultivation. According to the fertilizer requirement of broccoli crops, the soil fertilization performance and fertilizer effect put forward the rational ratio, dosage and corresponding fertilization techniques of organic fertilizer, NPK fertilizer and various micro-fertilizers before crop sowing.
1. Characteristics of fertilizer requirement: Due to the long growing period of broccoli, the demand for nutrients is large, and the most needed amount is nitrogen and potassium. In addition, the demand for boron, magnesium, calcium and molybdenum is also large. According to research, broccoli requires about 7.70-180 kg of pure nitrogen, 2.10-3.20 kg of phosphorus pentoxide, and 9.20-12 kg of potassium oxide for every 1000 kg of flower bulb produced. Before the bud, the nutrient absorption is less, and the demand for nutrients gradually increases after the bud, until the flower ball is inflated, the nutrients need the most, and the absorption rate is the fastest. Therefore, in the process of flower bud differentiation and flower ball development, phosphorus should be guaranteed. , the full supply of potassium nutrition.
2. Requirements for soil: The soil grown by broccoli is rich in organic matter, and the pH value is 5.50-6.60. The sandy loam and loam with strong water and fertilizer retention capacity are the optimum soil. The soil moisture requirement is 70%-80%, and the air relative humidity is 80-90%.
3, fertilization technology: 1 base fertilizer: early maturing varieties short and rapid growth period, high nutrient requirements in the early stage, organic fertilizer mainly livestock and poultry manure, and with NPK compound fertilizer; middle and late maturity varieties instead of compost, manure With phosphorus and potassium fertilizer. The amount of per mu is 1000-2000 kg for human and animal manure or 3000-5000 kg for manure, and 20-25 kg for 45% compound fertilizer. 2 Top dressing: In the seedling stage, combined with watering, the first application of ammonium sulfate 15 kg / mu, 20 days after the second top dressing, applying dried manure or chicken manure 400-500 kg / mu and watering, flower bud diameter of 2-3 When the centimeter is the third top dressing, apply 45% compound fertilizer 20-25 kg. In the later stage, 0.20% potassium dihydrogen phosphate and 0.20% borax were sprayed on the foliar surface.
Second, the principle of fertilization 1, mainly organic fertilizer, supplemented by chemical fertilizer: broccoli field single application of chemical fertilizer is higher than nitrate residue in single application of organic fertilizer. Therefore, the fertilizer for the production of pollution-free broccoli must be based on organic fertilizer, supplemented by mineral chemical fertilizers and trace element fertilizers, and vigorously strengthen the formula fertilization.
2. Limited use of nitrogen fertilizer: Nitrogen fertilizer is a variety that is used in the production of broccoli and is essential throughout the growth period. When the nitrogen fertilizer is sufficient, the plants grow vigorously, the leaves are dark green and high in yield. In the absence of nitrogen fertilizer, the stems and leaves of the plants are narrow, the leaves are yellow, and the yield and quality are reduced. However, excessive application of nitrogen fertilizer can also cause a sharp increase in nitrate content in vegetables, which is prone to pests and diseases.
3. Promote balanced fertilization: In the cultivation of broccoli, the focus of broccoli on the demand of various elements in different sowing dates is different. The nitrogen fertilizer is used as the leaf fertilizer, the phosphate fertilizer is used as the fruit fertilizer, and the potassium fertilizer is used as the root fertilizer. If a fertilizer is simply applied, The overall growth of broccoli has an adverse effect.
4. It is forbidden to list the broccoli immediately after the application of nitrogen fertilizer: After the last application of nitrogen fertilizer in broccoli, there must be a safe interval between the products and the product harvesting. It should be listed on the 8th day after the last application of nitrogen fertilizer.
5, vigorously promote root dressing, plants rely mainly on the roots to absorb nutrients, leaves and tender stems can also directly absorb nutrients from the solution sprayed on its surface. Therefore, it should be strongly advocated. Urea and superphosphate and potassium dihydrogen phosphate, as well as some trace elements, are suitable as top dressings.
6. Determine the fertilization period according to the physiological characteristics of broccoli. Cauliflower requires less nutrients during seedling stage, and requires more nutrients during vigorous growth and product formation. Organic fertilizer and phosphate fertilizer are generally used as base fertilizer before broccoli sowing and planting, and quick-acting nitrogen and potassium fertilizer can be used as top dressing in the middle of broccoli. The number of top dressings can be determined according to the growth and development of broccoli, usually 1-2 times every 15-20 days.
Third, broccoli uses fertilizer types. In the production of pollution-free broccoli, the fertilizers allowed for broccoli are basically divided into 4 categories:
(1) Organic fertilizer: including human and animal excrement, compost, manure, biogas fertilizer, green manure, crop straw, mud fertilizer, cake fertilizer, grass ash, slag, etc. All the plants except ash and slag should be fully decomposed before application. (After high-temperature fermentation, organic manure can kill 100% of pathogenic microorganisms such as E. coli, which can reduce volume and weight by 1/2-1/3, which is convenient for field transportation. In addition, the unfertilized organic fertilizer is applied to the field. Fermentation, easy to burn vegetable roots.) (2) Biological fertilizer: including humic acid fertilizer, rhizobial fertilizer, phosphorus bacterial fertilizer, compound microbial fertilizer. (3) Inorganic fertilizers: such as ammonium sulfate, urea, superphosphate, potassium sulfate, etc., NPK fertilizers that contain neither chlorine nor nitrate nitrogen, and special broccoli fertilizers produced everywhere. (4) Trace element fertilizer: It is a fertilizer formulated mainly from trace elements such as copper, iron, boron, zinc and molybdenum and beneficial elements.
The general principle of broccoli formula fertilization is according to the need of fertilization during the growth process, what nutrients are lacking, what fertilizer is applied; how much fertilizer is applied, how much fertilizer is applied; broccoli formula fertilization technology should be promoted everywhere, and broccoli special fertilizer is advocated. This not only can coordinate the contradiction between soil and crop nutrient supply and demand, reduce the waste caused by blind application of excessive nitrogen fertilizer, but also avoid the accumulation of phosphorus in the soil and the excessive consumption of potassium, which is conducive to maintaining soil nutrient balance and thus improving soil fertility. To lay the foundation for the sustainable development of broccoli production.
Source: Ningbo Agricultural Economic Net
Non-polluted cauliflower formula fertilization technology
As the main variety of the production and development of pollution-free vegetables in our county in recent years, broccoli production has attracted more and more attention. Improve the quality of broccoli, comply with the strict requirements of market standardization on the quality of broccoli, prevent and control the heavy metals such as nitrate, nitrite, cadmium and chromium in broccoli due to improper fertilization measures, and the product quality can not meet the requirements. Therefore, in order to make the broccoli high-quality and high-yield, the balanced formula fertilization is implemented, and the economic and effective fertilizer effect is fully exerted, and the yield of broccoli caused by the customary experience of fertilization is high and unstable. This formula has been developed to apply fertilizer.
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