The Best Fertilization Timing for Rice and the Amount of Compound Fertilizer to Apply per Mu as Topdressing
The growth of any crop cannot be separated from fertilization, and rice is especially important, so how do you fertilize for high rice yields? What time is best for fertilizing? What fertilizer to use for topdressing? How much compound fertilizer is needed per 1 mu of land?
What time is best for fertilizing rice
1. Fertilization amount. The fertilization amount for rice can be calculated based on the expected yield, the rice's nutrient requirements, the soil's nutrient supply, and the nutrient content and utilization rate of the fertilizer applied.
2. Fertilization stages. It can be divided into 4 stages: base fertilizer, tillering fertilizer, ear fertilizer, and grain fertilizer (chosen according to the growth vigor of the rice). The fertilization time and distribution ratio for each stage are as follows.
(1) Base fertilizer. Applied to the soil before rice transplanting, the base fertilizer accounts for 40% of the total chemical fertilizer and is applied together with the final harrowing of the field. On the basis of applying farmyard manure, generally apply one set of Chongzhidao with tubi jia per mu by flushing.
(2) Tillering fertilizer. The tillering stage is an important period for increasing the number of plants, and it is applied half a month after transplanting or seedling planting. Apply one bucket of Jiuguo per mu by flushing with water, and spray Huaguo Yisheng Guoneng multi-element on the leaves to supplement trace elements and promote tillering.
(3) Ear fertilizer. It is divided into flower-promoting fertilizer and flower-preserving fertilizer. Flower-promoting fertilizer is applied from the rachis differentiation stage to the spikelet differentiation stage; applying nitrogen at this stage can increase the number of spikelets per ear. Flower-preserving fertilizer is applied slightly before the pollen mother cell meiosis stage and has the effect of preventing spikelet degeneration and increasing the accumulation of storage materials in the stem and sheath. Apply one set of Chongzhidao with tubi jia per mu by flushing.
(4) Grain fertilizer. Grain fertilizer has the effect of extending leaf function, increasing photosynthetic intensity, increasing grain weight, and reducing empty and shriveled grains. Especially for rice fields with a relatively small population and varieties with large ears and a long grain-filling period, it is recommended to apply a small amount of urea, but nitrogen must not be excessive, so as to avoid delayed maturity due to excessive vegetative growth. Apply 10-15 kg of Defuer drip irrigation fertilizer per mu by flushing.
Main fertilization methods for rice
1. Light early - heavy middle - supplementary late method: Apply sufficient and appropriate base fertilizer and tillering fertilizer, reasonably apply ear fertilizer, and apply grain fertilizer as appropriate, so as to achieve early growth and steady growth, no excessive growth in the early stage, flower promotion in the middle stage, and no premature aging in the late stage. On the basis of ensuring sufficient ears, this method also aims at large ears and grain weight. This fertilization method is mostly used for single-season late rice and late-maturing middle rice in the south.
2. Stable early - attack middle method: This method saves fertilizer and gives stable, high yields. It mainly improves the effective tillering rate, attacks large ears to increase the seed-setting rate, and increases grain weight to strive for high yield. Characteristics: strong plants with large tillers and a small population, controlling tillering in the early stage; strong stems and roots, attacking large ears in the middle stage, and attacking the seed-setting rate and ear weight in the middle-late stage.
3. Promote early - control middle - supplement late method. This method is similar to the “V”-shaped fertilization method, heavily applying base fertilizer (accounting for more than 80% of the total) and heavily applying tillering fertilizer, and applying grain fertilizer as appropriate, so as to achieve the requirements of “bursting up in the early stage, remaining stable in the middle stage, and being healthy and strong in the late stage.” This fertilization method is mostly used in the Northeast rice region, most of the early rice in the south, and wheat stubble rice in North China. Its drawback is that excessive early growth easily causes field shading and relatively severe pests and diseases.
4. Promote early fertilization method. On the basis of applying sufficient basal fertilizer, apply tillering fertilizer early and heavily, especially nitrogen fertilizer, to promote early and rapid tillering and ensure more tillers and more ears. Basal fertilizer accounts for 70% of the total fertilizer amount (nitrogen fertilizer accounts for 60%-80% of the total nitrogen), and the remaining 30% of the fertilizer is all applied after transplanting and greening. This method is suitable for rice areas where rainfall is concentrated during the rice growth period, fertilizer is easily lost, and low temperature and insufficient sunlight often occur. Basal fertilizer is mainly farmyard manure.
5. One-time clear basal fertilization method. Apply all fertilizer at once when preparing the field, so that soil and fertilizer are fully mixed. It is suitable for rice fields with strong fertilizer retention such as clay and heavy loam, and with sufficient fertilizer sources. With this method, compared with basal fertilizer plus tillering fertilizer and basal fertilizer plus ear fertilizer, the nitrogen uptake rate of rice plants increases, tillering is fast, more ears are formed, the light transmittance between rows is high, and the yield increases by 3.6%-17.9%.
6. Soil testing and formula fertilization method. Soil testing and formula fertilization is a fertilization technical system that coordinates the interrelationships among crop yield, agricultural product quality, soil fertility, and the crop environment. According to the crop's fertilizer requirement patterns, soil fertilizer supply characteristics, and fertilizer effects, it combines organic fertilizers with inorganic fertilizers, appropriately proportions essential nutrient elements and trace elements, and adopts corresponding fertilizer application methods. This method can scientifically match the ratios and application amounts of various nutrients according to the soil nutrient test results and the amounts of various nutrients required throughout the crop's life, supply them reasonably, and meet the nutrient needs throughout the crop's life, so as to achieve the goals of increasing yield and efficiency; reduce unnecessary fertilization, lower costs, reduce environmental pollution, and alleviate soil compaction and pests and diseases.
What fertilizer to use for rice topdressing
Topdressing is mainly nitrogen fertilizer. If the total topdressing amount per 667 sq m does not exceed 30 kg of ammonium sulfate, the approximate fertilizer distribution is as follows: ① Surface fertilizer. Applied when harrowing the field before transplanting, 3-5 kg of ammonium sulfate per 667 sq m. ② Tillering fertilizer. Applied 10-15 days after transplanting, 5-10 kg of ammonium sulfate per 667 sq m. ③ Ear fertilizer. Applied at the early jointing stage, 8-10 kg of ammonium sulfate per 667 sq m. ④ Grain fertilizer. Applied 7 days before heading, 3-5 kg of ammonium sulfate per 667 sq m.
How much fertilizer does one mu of rice need
Single-season rice has a longer growth period and higher yield, generally growing for 90-120 days, with a yield of more than 500 kg per mu. Therefore, the fertilization amount is relatively high, but the proportion of basal nitrogen is relatively low, accounting for about 50%, and tillering fertilizer and booting fertilizer are equally important. The specific fertilization plan is: apply 8-12 kg of urea or 20-30 kg of ammonium bicarbonate per mu as basal fertilizer, and 8-10 kg of potassium chloride. Compound fertilizer can also be applied, 30-40 kg per mu. Basal fertilizer is applied when preparing the land before transplanting. Topdressing is divided into two applications: apply tillering fertilizer 10-15 days after transplanting, 8-10 kg of urea per mu; apply booting fertilizer 35-40 days after transplanting, 10-12 kg of urea or 25-35 kg of ammonium bicarbonate per mu.
Double-season rice is further divided into previous-crop early rice and subsequent-crop late rice. Two points should be noted in fertilization: First, treat the two crops as a whole, giving phosphorus fertilizer mainly to the previous crop and potassium fertilizer mainly to the subsequent crop. Second, compared with single-season rice, double-season rice has a shorter growth period, generally not exceeding 90 days, and lower yield, mostly 400-500 kg per mu. Therefore, the fertilization amount is less than that of single-season rice. Because the growth period is short, the nutrient absorption peak is relatively concentrated and advanced, so base fertilizer and early topdressing should be applied heavily. Booting fertilizer can be applied appropriately less, or only some foliar fertilizer can be sprayed. The specific plan is: apply 10-15 kg of urea per mu as basal fertilizer, or 30-40 kg of ammonium bicarbonate, 20-25 kg of superphosphate or calcium magnesium phosphate, and 8-12 kg of potassium chloride. Apply tillering fertilizer 10-15 days after transplanting, 5-10 kg of urea or 15-25 kg of ammonium bicarbonate per mu. Apply booting fertilizer as appropriate 30-35 days after transplanting, 3-5 kg of urea per mu, or spray foliar fertilizer twice. Foliar fertilizer concentration: urea 0.5% to 1%, potassium dihydrogen phosphate 0.2%-0.3%.