Four key points to master in rice fertilization

First, pay attention to applying sufficient organic fertilizer. Organic fertilizer contains various nutrients, can improve soil aeration and its characteristics of absorbing fertilizer and retaining water, promote robust growth of rice plants, and achieve high yield and good quality. Organic fertilizer is mainly used as base fertilizer, applying 30-40 loads of decomposed farmyard manure per mu, or 30-40 kg of cake fertilizer, and 40-50 loads of human and livestock manure can also be applied after plowing and before flooding.

Second, pay attention to controlling nitrogen fertilizer. Excessive application of nitrogen fertilizer to rice will not only cause an increase in ineffective tillering, greening, lodging, and intensified pests and diseases, leading to more empty and shriveled grains, a decline in the seed-setting rate, and affecting rice yield. Nitrogen fertilizer is mainly used as topdressing. The first time, after rice transplanting, apply 6-7 kg of urea per mu; the second time, 13-15 days after transplanting, combined with weeding, apply 4-5 kg of urea per mu to promote tillering and strong stems. In the mid-term, pay attention to drainage and fertilizer control, and only apply some balanced fertilizer as appropriate to the weaker second- and third-grade seedlings. In the later stage, according to the seedlings, supplement 3-4 kg of grain fertilizer as topdressing.

Third, pay attention to emphasizing the application of phosphorus and potassium fertilizers. Phosphorus and potassium fertilizers can enhance plant vitality, promote nutrient synthesis and transport, strengthen photosynthesis, prolong the functional period of leaves, make grains full and plump, and increase yield. Phosphorus fertilizer is suitable as base fertilizer, while potassium fertilizer is better as topdressing. In fields with sufficient organic fertilizer, apply 20-40 kg of phosphorus fertilizer per mu as base fertilizer, and before tillering, 3.5-5 kg of potassium chloride can be applied per mu as topdressing. Spraying phosphorus and potassium fertilizers on rice in the later stage can promote grain filling and seed setting. Spray once each at the late heading and flowering stage and at the grain-filling stage, using 50-100 g of phosphorus and potassium fertilizer per mu each time, diluted with 50-60 kg of water, and sprayed in the evening.

Fourth, pay attention to increasing the application of trace element fertilizers. Zinc fertilizer and silicon fertilizer can not only improve the oxygen supply to rice roots, enhance the stress resistance and lodging resistance of rice plants, improve the disease resistance of plants, promote root development in the later stage, prolong the functional period of leaves, and prevent premature aging; they can also accelerate flower development, increase the number of pollen grains, promote pollen germination, and help increase the ear-bearing rate of rice; moreover, they can promote larger ears and more grains, improve the seed-setting rate and grain plumpness, and increase rice yield.