When is the best time to fertilize rice? What kind of fertilizer do you use for topdressing? How much compound fertilizer should be applied to one mu of land?

The growth of any crop is inseparable from fertilization, rice is especially important, so how to apply fertilizer for high yield of rice? When is the best time to fertilize? What kind of fertilizer do you use for topdressing? How much compound fertilizer should be applied to one mu of land?

When is the best time to fertilize rice?

1. Amount of fertilizer applied. The amount of fertilizer applied to rice can be calculated according to the expected yield, the nutrient requirement of rice, the supply of soil nutrients, and the nutrient content and utilization rate of fertilizers applied.

2. Fertilizer application period. It can be divided into four stages: basal fertilizer, tiller fertilizer, panicle fertilizer and grain fertilizer (depending on the growth potential of rice). The fertilization time and distribution ratio in each period are as follows.

(1) base fertilizer. Rice was applied to the soil before transplanting, and the base fertilizer accounted for 40% of the total chemical fertilizer, combined with the last rake application. On the basis of applying farm manure, the application of soil per mu is generally more than one set of soil.

(2) Tillering fertilizer. The tillering stage is an important period to increase the number of plants, which is applied half a month after transplanting or transplanting seedlings. One barrel of fruit per mu is flushed with water, and foliar spraying of flower and fruit doctor fruit can supplement multi-elements and promote tillering.

(3) ear fertilizer. It is divided into flower-promoting fertilizer and flower-protecting fertilizer. The flower-promoting fertilizer was applied from the panicle axis differentiation stage to the spikelet differentiation stage, and nitrogen application could increase the number of spikelets per panicle. Flower-protecting fertilizer is applied before the meiosis of pollen cells, which can prevent spikelet degeneration and increase the accumulation of stem and sheath storage. There is more soil per mu than one set per mu.

(4) grain fertilizer. Grain fertilizer can prolong leaf function, increase photosynthetic intensity, increase grain weight and reduce empty grain. Especially for rice fields with small population and varieties with large panicle type and long filling period, it is recommended to apply a small amount of urea, but not partial nitrogen, so as to avoid greedy green and late ripening. 10-15 kg of drip fertilizer per mu.

Main fertilization methods for rice

The main results are as follows: 1. The method of pre-light-medium-heavy-back supplement: adequate application of basal fertilizer and tiller fertilizer, reasonable application of panicle fertilizer and grain fertilizer to achieve early growth and stable growth, not crazy in the early stage, flower promotion in the middle stage, and no premature senescence in the later stage. On the basis of ensuring enough panicles, this method also attacks large panicles and grain weight. This fertilization method is often used in single-cropping late rice and late-maturing middle rice in South China.

2. The former stable method to attack the middle method: this method saves fertilizer, stable yield and high yield. It is mainly to improve the effective tillering rate, attack the big ear to increase the seed setting rate, and increase the grain weight to compete for high yield. Characteristics: strong plant large tiller small population, early tiller control; official stalk strong root, middle attack big ear, middle attack seed setting rate and ear weight.

3. The method of pre-promotion, middle control and post-supplement. This method is similar to the "V" type fertilizer application method, with heavy application of base fertilizer (more than 80% of the total) and heavy application of tiller fertilizer and grain fertilizer to meet the requirements of "sensational success in the early stage, stable in the middle stage, and healthy and strong in the later stage". This fertilizer application method is mostly used in northeast rice region, most of southern early rice and wheat stubble rice in North China. The disadvantage is that the early growth is too prosperous, which is easy to cause field depression and serious diseases and insect pests.

4. The method of promoting fertilizer application before. On the basis of sufficient basal fertilizer, early and heavy application of tiller fertilizer, especially nitrogen fertilizer, in order to promote the early growth and rapid development of tillers and ensure the increase of tillers and panicles. The base fertilizer accounts for 70% of the total fertilizer (nitrogen fertilizer accounts for 60%-80% of the total nitrogen), and the remaining 30% fertilizer is applied after transplanting and turning green. This method is suitable for rice areas where rainfall is concentrated, fertilizer is easy to be lost, and low temperature and light often occur during rice growth. Farm manure is the main base fertilizer.

5. the method of clearing and applying fertilizer together with base fertilizer. During the whole field, all the fertilizers are applied at one time, so that the soil fertilizer is fully mixed, which is suitable for the paddy fields with strong fertility, such as clay and heavy loam, and the fertilizer source is sufficient. By using this method, the nitrogen absorption rate of rice plants with base fertilizer plus tillering fertilizer and base fertilizer plus panicle fertilizer increased, the tillers were faster, the panicles formed more, the light transmittance between rows was higher, and the yield was increased by 3.6% to 17.9%.

6. Soil testing formula fertilizer application method. The purpose of soil testing and formula fertilization is to coordinate the relationship between crop yield, agricultural product quality, soil fertility and crop environment, according to the law of crop fertilizer demand, soil fertilizer supply characteristics and fertilizer effect, a set of fertilization technology system which combines organic fertilizer with inorganic fertilizer, proper proportion of essential nutrient elements and trace elements, and adopts corresponding fertilizer application methods. According to the determination results of soil nutrients and the amount of various nutrients needed by crops in their lifetime, this method can scientifically match the proportion and application amount of various nutrients, supply reasonably, meet the nutrients needed in crop life, achieve the purpose of increasing production and efficiency, and reduce unnecessary fertilization. reduce the cost, reduce the pollution to the environment, reduce the soil consolidation and diseases and insect pests.

What kind of fertilizer is used for topdressing rice

Topdressing is mainly nitrogen fertilizer. If the total amount of topdressing does not exceed 30 kg of ammonium sulfate per 667m2, the general fertilizer distribution is as follows: ① flour fertilizer. When raking the field before transplanting, 3 kg of ammonium sulfate should be applied every 667 square meters. ② tiller fertilizer. 10-15 days after transplanting, 5-10 kg of ammonium sulfate was applied every 667 square meters. ③ spike fertilizer. At the early stage of jointing, 8kg of ammonium sulfate was applied every 667 square meters. ④ grain fertilizer. Seven days before heading, 3kg of ammonium sulfate was applied every 667 square meters.

How much fertilizer does one mu of rice need?

The growth period of single-cropping rice is longer and the yield is higher. Generally, it takes 90-120 days to grow, and the yield per mu is more than 500 kg. Therefore, the amount of fertilizer application is relatively high, but the proportion of basal fertilizer nitrogen is relatively low, accounting for about 50%, and equal attention is paid to tillering fertilizer and panicle fertilizer. The specific fertilization scheme is: urea 8kg / mu or ammonium bicarbonate 20kg / mu, potassium chloride 8kg / mu. You can also apply compound fertilizer, 30kg to 40kg per mu. Base fertilizer is applied during soil preparation before transplanting. Topdressing was divided into two stages, tillering fertilizer was applied 10-15 days after transplanting, urea 8-10 kg per mu, panicle fertilizer 35-40 days after transplanting, urea 10-12 kg or ammonium bicarbonate 25-35 kg per mu.

Double cropping rice is divided into early rice and late rice. Two points should be paid attention to in fertilization: one is to take the two crops as a whole, giving phosphate fertilizer mainly to the previous crop and potash fertilizer mainly to the following crop. Second, compared with single-cropping rice, the growth period of double-cropping rice is shorter, generally less than 90 days, the yield is lower, and the yield per mu is 400-500 kg. Therefore, the amount of fertilizer application is less than that of single cropping rice. Because the growth period is short, the nutrient absorption peak is relatively concentrated and in advance, so it is necessary to re-apply base fertilizer and early topdressing. Booting fertilizer can be applied less, or only some foliar fertilizer can be sprayed. The specific plan is: urea 10kg / mu, or ammonium bicarbonate 30kg / mu, calcium superphosphate or calcium magnesium phosphate fertilizer 20kg / mu, potassium chloride 8kg / mu. 10-15 days after transplanting, tiller fertilizer was applied, urea 5kg / mu or ammonium bicarbonate 15kg / mu. 30-35 days after transplanting, pregnant ear fertilizer should be applied as appropriate, urea 3-5kg per mu, or foliar fertilizer should be sprayed twice. the concentration of foliar fertilizer: urea 0.5% to 1%, potassium dihydrogen phosphate 0.2% 0.3%.