The author is an agricultural technician who often hears farmers' friends reflect that there are no shortages of chemical fertilizers every year, and they are all brand-name products, which are always less effective than Others. In fact, fertilization should also take into account the time and place, and may wish to find the reasons from the following aspects. Fertilization does not look at the thickness of the soil. Fertilizer can not be applied blindly, it should be applied by soil. For example, if nitrogen fertilizer is applied in the fertilizer field, the economic benefit is not high, and even there are side effects, if it is applied in the middle and low yield field, the yield increase effect is 2 to 3 times higher than that in the fertilizer field. Phosphorus fertilizer is applied in the phosphorus-deficient soil. The yield is about 3 times higher than that of the soil without phosphorus deficiency. In addition, considering the difference in soil texture, the sandy soil should be treated with organic fertilizers such as soil-fertilizers, and straw should be returned to the field to gradually improve the soil structure; clay soils generally have poor permeability and low fertilizer efficiency. Therefore, application of organic fertilizers must be sufficient. After maturity, application of chemical fertilizers should be advanced, and should "eat more and keep less," and avoid excessive nitrogen fertilizer in the later period; Loam texture is good, suitable for all types of crop growth, generally according to the output requirements and crop growth, timely and appropriate fertilization. Fertilizer should be combined with long-acting fertilizer and short-acting fertilizer, and organic fertilizer and chemical fertilizer should be used in combination to fertilize the soil and combine with fertilizer. Fertilizer does not look at the weather. The fertilization time in the low-temperature season should be appropriately advanced. When organic fertilizer is used as the basal fertilizer, it should be fully brewed and decomposed; the high-temperature weather fertilizer should be deepened to prevent the fertilizer from dispersing and burning. The soil is too wet, the chemical fertilizer should be applied shallowly, and the soil should be deeper than the dry soil. When the drought is low, the soil moisture content is low. After the chemical fertilizer is applied, the crop is difficult to absorb and use. It should be combined with irrigation or drizzle rain to fertilize; do not apply fertilizer before heavy rain or heavy rain to prevent fertilizer loss and leakage loss. Fertilizer has no look at crop species. For root and tuber crops, phosphorus and potassium fertilizers are mainly used, with nitrogenous fertilizer; leafy crops should be treated with more nitrogen fertilizer, and phosphorus fertilizers should be used appropriately; rice, corn, wheat and other crops need more nitrogen, and at the same time, phosphorus should be used. Potassium fertilizers; sugar cane, hemp, potato crops need nitrogen fertilizer, but also need potassium; legume crops rhizobia, with the ability to fix nitrogen in the air, the demand for nitrogen is less, so the main application of phosphate fertilizer . Fertilizer has no look at the mouthwash. For chillies, such as sweet potatoes, rice, cabbage, radish, because after the glutinous crops need to spend the winter and spring cold season, should be more sheep, donkey feces and other hot fertilizers; enthalpy, such as the former wolfberry is wheat, potatoes, etc. , There is sufficient time for leisure and sunburn. It is recommended to apply more cold-fertilizers such as pigs and cow dung that contain more moisture; for soft-cockroaches, such as peanuts and soybean meal, the soil is soft and there are more nitrogen fertilizers left, and more phosphorus should be applied. Potash fertilizers; For hard earthworms, such as corn, sorghum, and cotton pods, the soil should be hardened and organic fertilizer should be applied. Fertilizer does not look at the crop growth. Different growth stages of crops have different physiological characteristics, and the absorption and absorption time of fertilizers are also different. In the development stages of roots, stems and leaves, generally more nitrogen fertilizer is needed. For example, early rice has a short growing season, and the peak of nitrogen uptake appears during the period from greening to tillering after transplanting (15 to 20 days). Therefore, it is necessary to reapply manure, stable panicle fertilizer and grain fertilizer. The early growth of hemp crops is fast. The growth of plants and the formation of fibroblasts are almost simultaneously. Therefore, in addition to satisfying the requirement of nitrogen fertilizer, potassium fertilizer must be applied at the same time to meet the demand for nutrients. Fertilizer does not look at the nature of fertilizers. Fertilizers with relatively stable chemical properties, such as urea, diammonium phosphate and superphosphate, should be used as basal or seed fertilizers, or applied to the root layer in advance; chemically unstable and volatile fertilizers such as ammonia, ammonium phosphate, etc. Ammonium sulfate, ammonium nitrate and other fertilizers should be deep-sealed to reduce nutrient losses. Individual crops or fields need special fertilizers. For example, paddy fields should not be applied with nitrate nitrogen fertilizers, and ammonium nitrogen fertilizers should be applied. Sweet potato, potato, tobacco and other crops should not be chlorine, and ammonium chloride, potassium chloride and other chlorine-containing fertilizers should not be used.
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