Detailed Explanation of Key Points of Standardized Fertilization Technology for Rice
I. Fertilization Principles
1. Implement balanced fertilization According to the nutrient requirements of each crop, the soil nutrient supply status and the fertilizer effect, determine the corresponding fertilization amount and fertilization method. Based on the principle of combining organic fertilizer with inorganic fertilizer, and combining base fertilizer with topdressing, achieve balanced fertilization.
2. Implement harmless treatment of organic fertilizer Organic fertilizer produced and used by farmers themselves must undergo decomposition and fermentation, harmless treatment, and kill pathogenic microorganisms, insect eggs and weed seeds. It is prohibited to use industrial waste, urban garbage and sludge, as well as farmyard manure that does not meet the harmless treatment indicators.
3. Implement compounding and specialization of inorganic fertilizers The fertilizer types selected shall comply with the fertilizer varieties and quality requirements specified in the fertilizer quality standard (ny/t394), and organic-inorganic compound fertilizers and compound fertilizers specialized for various crops shall be selected as far as possible.
II. Standardized Fertilization Technology for Rice
Fertilization should emphasize heavy application of base fertilizer, early topdressing of tillering fertilizer, skillful use of panicle fertilizer, and supplementary application of grain fertilizer. The fertilization amount is based on nitrogen fertilizer as the standard, and the nitrogen-phosphorus-potassium ratio method is used to determine the amounts of phosphorus and potassium fertilizers. Apply 225-300 kg of urea per hectare. After the nitrogen fertilizer amount is determined, determine the amounts of phosphorus and potassium fertilizers according to nitrogen:phosphorus:potassium = 1:0.5:0.3-0.5.
1. Seedbed soil preparation For each square meter of seedbed soil, apply 10-15 kg of high-quality decomposed farmyard manure and 0.125 kg of strong seedling nutrient agent, mix evenly with the prepared sieved seedbed soil, with a seedbed soil thickness of about 10 cm and a pH value of 4.5-5.5.
2. Seedbed topdressing When seedlings show nutrient deficiency at the 2.5-leaf stage, use 1.5 g-2 g of ammonium sulfate and 0.25 g of zinc sulfate per square meter, dilute 100 times and spray on the leaves, and promptly rinse the leaf surfaces with clean water after spraying. Six days before lifting the seedlings, broadcast 150 g of diammonium phosphate per square meter, and spray clean water to wash the seedlings after topdressing.
3. Fertilization in the main field Increase the application of farmyard manure and reduce the application of chemical fertilizers. Apply 30 tons of decomposed organic fertilizer per hectare, incorporated in combination with dry harrowing; apply 112.5-150 kg of diammonium phosphate and 75 kg of potassium sulfate per hectare, incorporated into the whole layer in combination with water land preparation.
4. Topdressing Principles of rice topdressing: sufficient tillering fertilizer, steady panicle fertilizer, and light grain fertilizer.
(1) Tillering fertilizer From after transplanting to before tillering, apply 50-75 kg of urea per hectare.
(2) Panicle fertilizer Apply at the early jointing stage, 50-75 kg of urea and 50-75 kg of potassium sulfate per hectare. Increasing potassium fertilizer can improve the seed setting rate and 1000-grain weight, promote early maturity, and enhance disease resistance and lodging resistance.
(3) Grain fertilizer Apply before heading, 15-22.5 kg of urea per hectare. Although nitrogen uptake decreases after heading, if soil nitrogen supply is insufficient, the photosynthetic efficiency of leaves will be reduced. Appropriate topdressing of grain fertilizer can prevent premature senescence of roots and leaves.
(4) Foliar topdressing If zinc fertilizer was not applied as base fertilizer, 50-100 g of zinc sulfate can be formulated into a 0.2% aqueous solution for foliar supplementary application at the tillering stage. Liquid fertilizers containing silicon and selenium (use the concentration according to the instructions) can be sprayed on the leaves, which can enhance the disease resistance of rice, promote early maturity, improve the eating quality and nutritional quality of rice, and increase commodity value. Spraying liquid fertilizers such as 0.2%-0.3% potassium dihydrogen phosphate at the full heading to grain filling stage can prolong the survival rate of functional leaves at the late growth stage, accelerate the grain filling speed, reduce the empty grain rate, increase the 1000-grain weight, and have a certain effect on preventing delayed-type cold damage.