Scientific fertilization of Maize requires skill

First, principles. In fertilization, we should master the combined application of nitrogen, phosphorus, potassium and trace elements, balanced fertilization, deep application of fertilizer, stage-by-stage topdressing, combination of water and fertilizer to improve fertilizer efficiency. In terms of fertilizer application rate, various factors such as fertilizer absorption law, yield level, soil fertilizer supply capacity, fertilizer nutrient content and utilization rate of corn should be comprehensively considered.

Second, base fertilizer. The fertilizer applied before sowing is called base fertilizer. Generally, organic fertilizer, compound fertilizer or part of nitrogen fertilizer, potash fertilizer and micro-fertilizer are mixed and applied in ditch. If it is too late to apply it, it can be used as seedling fertilizer at once.

Third, grow fertilizer. When sowing, the fertilizer applied next to or along with the seed is seed fertilizer. It can meet the nutrient needs of maize at the initial stage of growth, and can promote the development of root system and the growth of seedlings. General per mu with diammonium phosphate or compound fertilizer, urea 3 kg, should do column fertilizer, fertilizer isolation, to prevent damage to seedlings.

Fourth, topdressing. The fertilizer applied in the growth period of corn is topdressing. The period, times and quantity of topdressing should reach the peak according to the law of fertilizer absorption, yield level, geographical basis and demand of corn. At this time, if the nutrient supply is insufficient, there will be falling flowers and fruits. Malnutrition will also affect the normal development of floral organs and fruits, such as small pollen and uneven style, which can not be pollinated normally and fall off.

Second, measures to prevent tomato from falling flowers and fruits. In order to prevent tomato from falling flowers and fruits, the following work should be done on the basis of timely sowing, cultivating strong seedlings, reasonable close planting, scientific fertilization and enhancing the stress resistance of plants. The main results are as follows: (1) to improve the amount of warm and wet strip fertilization in tomato flower and fruit stage.

1. The period and function of topdressing. (1) Seedling fertilizer: generally applied after seedling setting and before jointing, seedling fertilizer and jointing fertilizer can be applied at one time. It has the functions of promoting roots, strong seedlings, promoting leaves and strong culms, and lays a good foundation for many species and large ones. (2) seed fertilizer: when applied in the big trumpet mouth stage of corn, the most fertilizer is needed in this period, which is the key period to determine the size of fruit seed and the number of grains. It can promote large species and many grains. (3) Grain fertilizer: it is generally applied at the flowering stage. It can ensure the full supply of inorganic nutrients, prolong the functional period of green leaves, increase the accumulation of light and products, and promote grain number and grain weight to obtain high yield.

2. Classified topdressing. The main results are as follows: (1) High-yield fields: the foundation of soil fertility is good and the amount of topdressing is large, so it is best to adopt the three-attack topdressing method of light topdressing seedling fertilizer, heavy seed fertilizer and topdressing grain fertilizer. The amount of topdressing at seedling stage accounts for about 30% of the total topdressing, 50% for seed fertilizer and 20% for grain fertilizer. (2) Middle-yield fields: better soil fertility, more topdressing, it is appropriate to apply sufficient seedling fertilizer, heavy seed fertilizer twice topdressing method, seedling fertilizer accounts for about 40% of the total topdressing amount, seed fertilizer accounts for about 60%. (3) low yield: the soil fertility is poor, topdressing should adopt the method of heavy seedling fertilizer and light seed fertilizer, seedling fertilizer accounts for about 60%, seed fertilizer accounts for about 40%.

3. The method of topdressing. The depth of topdressing is generally about 10cm, the distance of topdressing at seedling stage is 10-12cm from maize plant, and the distance from seed fertilizer and grain fertilizer is 15-20cm. Only in this way can we give full play to the efficiency of fertilizer and improve the utilization rate of fertilizer.