Experts teach you about balanced fertilization - rice

Rice First, technical brief Balanced fertilization must master the principles of set production with soil, nitrogen production, deficiency due to deficiency, organic-inorganic combination, balanced application of nitrogen, phosphorus and potassium. The method is: First, soil testing. Soil testing is the premise of balanced fertilization. Through analysis and determination of soil nutrients, the soil fertility can be accurately grasped to provide scientific basis for balanced fertilization. Based on the analysis of soil nutrient investigation results of some rice crops in recent years, after the second general soil survey carried out in the 1980s, the content of alkali-hydrolyzable N and available P increased significantly, the content of available K decreased, and soil N supply and phosphorus supply decreased. Better performance, more severe potassium deficiency; second is formula. Formulation is the key to balanced fertilization. On the basis of soil testing, according to soil characteristics, climate characteristics, cultivation habits, production levels and other conditions, determine the target yield, put forward the most suitable amount of nitrogen fertilizer and the best ratio of nitrogen, phosphorus and potassium. The required fertilizer for rice is to absorb 2.0-2.4 kg of nitrogen, 0.9-1.4 kg of phosphorus pentoxide, 2.5-3.8 kg of potassium oxide per 100 kg of rice, and the ratio of nitrogen, phosphorus and potassium is about 1:0.5:1.3; The third is with fertilizer (fertilizer). Select high-quality, high-efficiency single fertilizer or special fertilizer, compound fertilizer, organic-inorganic compound fertilizer and other fertilizer varieties; Fourth, fertilization model. According to the soil type, the crop's fertility characteristics and fertilizer requirements, formulate the corresponding fertilization mode.
Second, the operating procedures According to the fertilizer characteristics of rice soil and fertilizer requirements of rice and production of underwater and other factors, 400-500 kg per mu rice balanced fertilization technical operating procedures are as follows:
1. Organic Fertilizer Dosage: According to the research, to make the soil organic matter be supplemented and updated, at least 2000 kilograms of organic fertilizer should be applied per acre per year. Therefore, to re-apply organic fertilizer, organic fertilizer accounts for about 50% of the total amount of fertilizer. Generally, the early rice uses 1500-2500 kilograms of fresh green manure or 1,000-1,500 kilograms of manure or 60-80 kilograms of commodity organic fertilizer per hectare. The late rice still returns 200-250 kilograms of dry straw or 1,000-1,500 kilograms of manure or 80-100 grams of organic manure per acre. kg.
2. The ratio of NPK: The rice yield is 400-500 kilograms per mu, requiring a total of 10-12 kilograms of pure nitrogen, 4.5-5.5 kilograms of phosphorus pentoxide, 13-16 kilograms of potassium oxide, and the ratio of nitrogen, phosphorus, and potassium is 1:0.4:1.3.
3. Fertilizer varieties selection: choose high-quality and high-efficiency urea, ammonium bicarbonate, calcium magnesium phosphate, or superphosphate; potassium sulfate or potassium chloride and other simple fertilizers or rice-specific fertilizers, compound fertilizers.
4, application period:
(1) Base fertilizer: organic fertilizer and phosphate fertilizer are all used as base fertilizer, and organic fertilizer is applied before plowing. When paddy field, 35-40 kg of calcium magnesium phosphate fertilizer and 15-20 kg ammonium bicarbonate are applied per mu, and potassium sulfate is 8- 10 kg or potassium chloride 6-8 kg.
(2) Dressing: Top dressing should be divided into two applications. The first top dressing is applied about 7 days after transplanting. Urea urea 7.5-9 kg, potassium sulfate 6-7.5 kg or potassium chloride 5-6 kg; The second top dressing is applied about 15 days after transplanting, with 8-10 kg of urea per mu, 10-12 kg of potassium sulfate or 8-10 kg of potassium chloride.
(3) Panicle fertilizer: young panicle differentiation period (about 25 days after early rice transplanting and 30 days after late rice transplanting). If the leaf color turns yellow, apply 2-2.5 kg of urea and 3-4 kg of potassium chloride per mu. .
(4) Spraying foliar fertilizer: spraying potassium dihydrogen phosphate or rice leaf foliar fertilizer at the booting stage and mature stage.