Latest Rice Fertilizer Requirement Patterns and Fertilization Techniques Tutorial

Rice Fertilizer Requirement Patterns

Rice is one of the crops with relatively high fertilizer requirements. Generally, producing 100 kg of rice grain requires 1.6-2.5 kg of nitrogen (N), 0.8-1.2 kg of phosphorus (P2O5), and 2.1-3.0 kg of potassium (K2O). The fertilizer requirement ratio of nitrogen, phosphorus, and potassium is approximately 2:1:3.

Rice's absorption of nitrogen peaks during the vigorous tillering stage and the heading and flowering stage. Applying nitrogen fertilizer can increase starch production, and starch production is positively correlated with rice grain size, yield level, and grain quality. If nitrogen supply is insufficient before heading, it will cause reduced grain nutrition, insufficient grain filling, and lower rice quality.

Rice's absorption of phosphorus shows little difference across growth stages, with the period of greatest absorption being from tillering to young panicle differentiation. Phosphorus fertilizer can promote root development and nutrient absorption, enhance tillering, increase starch synthesis, and promote grain filling.

Rice's absorption of potassium occurs mainly from panicle differentiation to heading and flowering, followed by tillering to panicle differentiation. Potassium is an essential nutrient for the synthesis and internal transport of starch and cellulose. It can improve root vitality, delay leaf senescence, and enhance resistance to pests and diseases.

In addition, two micronutrient fertilizers, silicon and zinc, have a relatively large impact on rice yield and quality. Rice stems and leaves contain 10%-20% silicon dioxide. Applying silicon fertilizer can enhance rice's resistance to pests and diseases and lodging, play a role in increasing yield, and improve rice quality; zinc fertilizer can increase the number of effective panicles, grains per panicle, and 1000-grain weight of rice, reduce the empty grain rate, and play a role in increasing yield, with a more obvious effect on calcareous soils. The application of silicon and zinc fertilizers is more effective in newly converted paddy fields, acidic soils, and cold waterlogged fields.

Rice Fertilization Techniques

1. Seedling bed fertilization

For seedling bed base fertilizer, high-quality organic fertilizer should be heavily applied. Organic fertilizer has long-lasting fertilizer effects, complete nutrients, and contains large amounts of nutrient elements essential for rice growth. Generally, apply 500-1000 kg per mu, and at the same time apply 3-5 kg of urea, 8-15 kg of diammonium phosphate, 7-8 kg of potassium chloride per mu, or apply 20-30 kg of compound fertilizer per mu, to achieve the purpose of uniform fertilizer supply and promote strong and uniform seedlings. 4-5 days before transplanting, apply 6-7 kg of urea or 8-10 kg of high-nitrogen compound fertilizer per mu as a send-off fertilizer, so that seedlings can quickly turn green and resume growth after transplanting.

2. Apply sufficient base fertilizer in the main field: The main field base fertilizer should also emphasize the application of organic fertilizer. Generally, apply 10-15 kg of Defuer drip irrigation flush fertilizer per mu. And apply one set of Chongzhidao soil-matching ratio plus. In addition, increase the application of 6-8 kg of silicon fertilizer and 1-1.5 kg of zinc sulfate per mu. The main field base fertilizer should be applied before transplanting in combination with plowing and harrowing the paddy field, and should be deeply applied into the soil at 12-20 cm, so that ammonium remains stable in a low-oxygen environment and is prevented from loss.

3. Topdressing

(1) Apply tillering fertilizer early. Apply tillering fertilizer as early as possible after transplanting and turning green, to promote the growth of low-node tillers and play a role in increasing panicles. Tillering fertilizer is generally applied in two applications, each time applying 10 kg of Defuer drip irrigation flush fertilizer per mu, ensuring uniform growth across the entire field and playing a role in preserving tillers to form panicles.

(2) Skillfully apply panicle fertilizer. When the penultimate leaf of rice begins to emerge and the young panicle is about 1 cm long, this is the foundational period for panicle formation and grain development, and ineffective tillering should be controlled. At this time, apply one bucket of Jiuguo per mu as topdressing, to ensure that sufficient nutrients in the middle stage turn toward reproductive growth, increase the number of spikelets, prevent spikelet degeneration, promote large panicles and heavy grains, and at the same time have the effects of nourishing roots, strengthening leaves, strengthening stems, and preventing lodging. For plots with too small a population, it can be applied earlier at the panicle differentiation stage.

(3) Supplement with grain fertilizer. From heading to maturity, the main focus is to increase the seed-setting rate, ensure full maturity, and increase 1000-grain weight. Topdressing should depend on the growth condition of the rice, and it is better to apply less rather than more. Generally, spray 50-60 kg per mu of a 0.2%-0.3% potassium dihydrogen phosphate solution mixed with Saisheng seaweed acid iodine; after zinc deficiency symptoms appear, spray 50-60 kg per mu of a 0.1%-0.3% zinc sulfate solution mixed with Huaguo Doctor fruit multi-element; for plots where leaves turn chlorotic and yellow before heading, apply one set of Chongzhidao soil-matching ratio plus per mu. Supplementing with grain fertilizer can effectively enhance the plant's stress resistance and disease resistance; extend the functional period of leaves and prevent premature senescence; improve the oxygen supply to rice roots and increase root vitality; accelerate grain filling, promote maturity and full grains, thereby increasing rice yield and improving rice quality. It should be noted that for fields with sufficient early-stage fertilizer, excessive and vigorous mid-stage tillering, dark green leaf color, poor light-receiving posture among the population, and a tendency toward delayed maturity with green leaves, grain fertilizer should not be applied as topdressing.

In addition, saline-alkali land should be drained and washed of salt before fertilization. About 3-4 days before fertilization, pay attention to irrigating during the day and draining at night, to prevent temporary salt accumulation from affecting the fertilizer effect.