How to choose the right spring corn fertilization plan for you?
Seed treatment When planting spring corn, use seed coating agents such as carbosulfan, imidacloprid, chlorpyrifos, etc. for seed dressing to prevent underground pests from damaging the sown corn seeds. When applying pesticide and sowing, evenly broadcast diazinon granules, or chlorpyrifos granules, or phoxim granules around the corn seeds, 6~... per mu.
There are two types of fertilization plans for planting spring corn in northern China this year. Plan One uses compound fertilizer with an appropriate ratio of nitrogen, phosphorus, and potassium, plus urea, diammonium phosphate, and potassium chloride, through the "old three-stage" fertilization method, that is, compound fertilizer as base fertilizer applied deep, diammonium phosphate as seed fertilizer applied shallowly below the seeds and separated, and urea as topdressing applied at the corn jointing stage. The advantage of the "old three-stage" fertilization method is that it can stably achieve high yields in different years, generally reaching a yield level of 600~800 kg per mu, with a high fertilization safety factor and relatively high utilization rate. However, the disadvantage of Plan One is that it is labor-intensive, and farmers are increasingly unwilling to accept it. In recent years, the fertilization methods in the main spring corn production areas of northern China have changed greatly. With the modern development of agricultural production, a trend toward simplification has emerged in cultivation and soil tillage. Although for many years agricultural science and technology extension has consistently advocated principles such as deep application of nitrogen base fertilizer, split and delayed application of nitrogen topdressing, and layered application of phosphorus base fertilizer and seed fertilizer, some new simplified fertilization plans have still developed rapidly, such as Plan Two, which uses the "one-shot" or "single application" fertilization method with high-nitrogen compound fertilizer. The so-called "single application" means applying all the fertilizer needed for the entire growth period of spring corn as base fertilizer at one time, with no further fertilization afterward. The advantage of this fertilization method is that it is simple and saves labor, but its effect varies by location and time. According to a survey in the black calcium soil region of Northeast China, about 60% of spring corn using one-time fertilization showed increased yield, 28% remained the same, and 10% showed decreased yield. However, survey results from alluvial soil areas show that the probability of increased yield decreased, and the possibility of reduced yield increased. These surveys indicate that the effect of this fertilization method is still unstable. In addition, the fertilization method of Plan Two has a relatively low safety factor, and farmers report more fertilization accidents.
The suitability of "single application" needs to be understood
Therefore, it is necessary to analyze the suitability of this fertilization method. First, it depends on the grower's requirements for yield goals and indicators of safe and stable production. Even under normal years and with the same nutrient input, one-time fertilization cannot be better than split fertilization, as shown by the fact that the yield level of spring corn generally does not exceed 500~600 kg per mu.
This is because the effect of one-time fertilization is controlled by many factors, such as fertilizer composition, quality, application position, sowing period, temperature, and hydrothermal conditions. In some situations, it is not suitable to adopt "one-shot" or "single application."
Taking everything into consideration, the suitable conditions for one-time fertilization are mainly in the arid and low-rainfall areas of the west, while many places are unsuitable. For example, in irrigated land in North China, it can cause corn seedlings to fail to establish properly in the early stage and then suffer from fertilizer deficiency in the later stage, making yield difficult to guarantee; another example is Central China and South China, where annual rainfall is high. If all chemical fertilizer is applied at once for corn fertilization, it will cause excessive vegetative growth in the early stage and fertilizer deficiency during grain filling, thus leading to reduced yield.