Extensive application of organic fertilizers. Corn is a high-yield crop, and its yield level is closely related to the level of soil fertility. In high-yield fertilization measures for corn, the first step is to apply organic fertilizers extensively to improve soil fertility. Generally, the input amount of organic fertilizer per acre should not be less than 4000 kg.
Apply nitrogen fertilizer steadily. For spring corn, apply a good base fertilizer and regulate the amount of topdressing, and for summer corn, apply a good topdressing. In high-yield fields with a yield of more than 500 kg, nitrogen application per mu should be stable at 9-12 kg; for medium-yield fields with a yield of 300-500 kg, nitrogen application per mu should be stabilized at 7-10 kg; and in low-yield fields with a yield of less than 300 kg , Nitrogen application per mu should be stable at 6-8 kg. At the same time, reasonably adjust the application period and method to improve the effect of nitrogen fertilizer utilization.
Control the application of phosphate fertilizers. At present, the role of phosphate fertilizer has been widely recognized, but the application of phosphate fertilizer should be determined and controlled reasonably according to the effective phosphorus content of the soil. In fields with high, medium and low yields, the appropriate phosphorus application rate per mu should be controlled within the range of 7 kg, 6 kg and 5 kg respectively. Phosphate fertilizers for spring maize are generally used as basal fertilizers, and for summer maize, they can be applied with the application of nitrogen fertilizers. Phosphate fertilizer application should emphasize deep application and early application.
Increase the application of potash fertilizer. As the soil potassium decreases year by year, the area of potassium deficiency continues to expand. In order to meet the potassium demand for corn growth, it is necessary to increase the application of potassium fertilizer. The appropriate potassium fertilizer application rate in high-yield fields is about 8 kg per mu, middle-yield fields are about 7 kg, and low-yield fields are about 6 kg. The application ratio of nitrogen, phosphorus, and potassium should be 1:0.5:0.6.
Apply micro-fertilizers. Due to the improvement of maize varieties, the reform of farming system and the change of fertilization structure, the symptoms of microelement deficiency in the soil have become more and more obvious, especially the symptoms of zinc deficiency in maize have appeared on a large scale. Supplemental application of zinc fertilizer for corn can be applied in corn seed soaking, coating, etc., and 1-2 kg of zinc sulfate can be generally applied during corn sowing or topdressing at seedling stage. It can also be used in special fertilizer for corn or corn seedling. Foliar spray, zinc fertilizer is added to the spray fertilizer.