For high yields in rice of the grass family, what fertilizer application rates and methods should be used?

Rice is the most important and longest-cultivated grain species in the genus Oryza, and is a direct cash crop. For growers, how to fertilize rice to achieve high yields is of great concern, so what is the fertilizer application rate for rice? And what are the methods? In fact, to achieve high yields you need to pay attention to “nutrition”, which means fertilizing well. When fertilizing, you need to pay attention to the application rate and methods.

Fertilizer application rate for rice

The fertilizer requirement of rice over its whole life is that for every 100 kg of rice grain, it needs to absorb 2.0~2.4 kg of nitrogen, 0.9~1.4 kg of phosphorus pentoxide, and 2.5~2.9 kg of potassium oxide. The fertilizer application rate for rice should be determined based on factors such as the soil's nutrient supply capacity, the target rice yield, fertilizer use efficiency, and the properties of various fertilizers. The soil's fertilizer supply can be estimated at about 60% of the total fertilizer requirement of rice; fertilizer use efficiency varies somewhat with the season: nitrogen fertilizer use efficiency is 30%~40%, potassium fertilizer use efficiency is about 40%, superphosphate is about 30%, and organic fertilizer use efficiency is about 20%. Taking into comprehensive account factors such as soil supply capacity, fertilizer use efficiency, and production level, under medium soil nutrient conditions, a rice yield of 500 kg per mu requires the application of about 12 kg of nitrogen fertilizer (N), 5.5 kg of phosphate fertilizer (P2O5), and 10 kg of potassium fertilizer (K2O).

Fertilization over the life of rice can generally be divided into base fertilizer, tillering fertilizer, and panicle fertilizer.

1. Base fertilizer is the fertilizer applied to the soil before rice transplanting. Try as much as possible to combine organic fertilizer with inorganic fertilizer. Base fertilizer should account for about 50% of the total nitrogen fertilizer, and is generally applied in combination with the last harrowing before transplanting.

2. Tillering fertilizer should be applied early, generally accounting for about 30% of the total nitrogen fertilizer, and applied within 1 week after transplanting or seedling transplanting.

3. Panicle fertilizer can be divided into flower-promoting fertilizer and flower-preserving fertilizer according to the timing of the topdressing and the role of the fertilizer applied, but in production practice, panicle fertilizer is generally not divided into flower-promoting fertilizer and flower-preserving fertilizer, and is applied 40~50 days after transplanting, generally accounting for about 20% of the total nitrogen fertilizer.

4. After heading and flowering, determine the application of grain fertilizer according to the variety type and growth conditions. Generally, it can be sprayed once each in the late heading and flowering stage and the grain-filling stage, using 150 grams of potassium dihydrogen phosphate per mu each time, diluted in 50~60 kg of water and sprayed in the evening, to increase grain weight and reduce empty and shriveled grains.

Fertilization methods for rice

1. Value chemical fertilizers and combine them with organic fertilizers. The combined application of organic and inorganic fertilizers has a very significant effect on improving and enriching the soil. It can increase the soil's organic matter reserves, improve the composition of soil organic matter, increase the content of nitrogen, phosphorus, potassium, and trace elements in the soil, strengthen the soil's fertilizer retention and supply capacity, and improve the soil's physical properties and moisture conditions.

2. Combined application of nitrogen and phosphorus fertilizers, or nitrogen, phosphorus, and potassium. Under high-yield cultivation conditions, rice is prone to excessive vegetative growth, lodging, and rice blast, with an increase in the empty and shriveled grain rate. Therefore, in fertilization, one must insist on the combined application of nitrogen, phosphorus, and potassium.

3. Appropriate application rates and formula fertilization. Under high-yield cultivation, the fertilizer application rate must be appropriate and the ratio reasonable. Different application rates should be determined according to plots with different fertility levels, so as to achieve formula fertilization and ensure high yields.

Finally, note that to achieve high rice yields, you must also prevent and control diseases and insect pests well.

1. The control target must be clear: according to the different types of diseases and insect pests in the field, adopt corresponding pesticide control. When mixing pesticides, their content must be clearly understood, especially for the control of panicle neck blast; tricyclazole has 2 dosage forms, and you must not get them mixed up.

2. Do not arbitrarily increase the amount of pesticide used.

3. Select disease-resistant varieties and fertilize reasonably.