Basal fertilizer is a fertilizer applied in combination with soil tillage before sowing or transplanting and planting crops. The purpose is to create good soil nutrient conditions for the growth and development of spring crops to meet the basic requirements for soil nutrients throughout the crop growth period. To this end, basal fertilizer application should have the following three characteristics:
Fertilizer sources are diverse and integrated, and fertilizer seasons are better than those of Changchun crops. Since the basal fertilizer can be combined with deep ploughing, organic fertilizers and chemical fertilizers are applied to the soil at the same time, not only providing crop nutrition, but also fertilizing the soil and realizing the combination of land-cultivation for the purpose of sustaining production increase. Actually, in addition to the large-scale application of organic fertilizers to economic crops such as vegetables and fruits, field grain crops and even cotton use only chemical fertilizers as base fertilizers. Fertilizers used as base fertilizers can be either compound fertilizers or single fertilizers. The proportion of compound fertilizers used as base fertilizers is now rising year by year, and the selection of medium-high and special-purpose compound fertilizers is increasing year by year. In the nutrient ratio of compound fertilizers, general-purpose and medium-nitrogen-phosphorus medium-potassium types are more suitable as base fertilizers, while high-nitrogen, low-phosphorus, and low-potassium compound fertilizers are not suitable as base fertilizers.
Larger application rates determine the amount of basal fertilizer to be sufficient. However, the total amount of recommendations is still based on soil test results and the law of crop fattening. The so-called large amount of application is relative to seed fertilizer and topdressing, not blind increase. For the three elements of nitrogen, phosphorus and potassium, the proportion of basal fertilizer is different. The ratio of basal fertilizer of phosphorus and potassium accounts for 80% to 90% of the total recommended amount of the crop, which means that both phosphorus and potassium are basically used in basal fertilizer. However, nitrogen fertilizers are different, requiring up to half of the nitrogen fertilizers to be used as base fertilizers, and half or more of the nitrogen fertilizers should be used as top dressings with high fertilization efficiency.
The application method must be done in the right fertilizer location. The application amount of base fertilizer should be combined with the mechanical tillage operation. The fertilizer can be applied to the appropriate depth and the position is in the root zone of the crop. This results in high efficiency of fertilization. Therefore, the basic fertilizer is used together with roots. Layer farming is performed simultaneously and closely. In particular, when organic fertilizers, compound fertilizers, and nitrogen, phosphorus, and potassium fertilizers are used in combination, a large amount of fertilizer is applied to a certain depth and mixed with the soil by plowing or rotary tillage; tillage and basal fertilization of spring sowing crops in most parts of the north are currently conducted. Rotary ploughs are mainly used. Rotary ploughs can be used to complete the three operations of plows, rakes and flats. However, rotary cultivator operation depth is shallow, generally 10 to 12 centimeters. Particular attention should be paid to the fact that the amount of fertilizers, especially nitrogen fertilizers, is too large and there is a risk.
The position and distribution of basal application should be seen from both horizontal and vertical directions. Spreading is to evenly spread the organic fertilizer and compound fertilizer on the surface of the soil, and then use a ploughshare to turn the fertilizer into the soil. This method is suitable for dense planting crops. The application is to apply fertiliser (including compound fertilizer and single fertilizer) strips of fertiliser with a width of about 5 centimeters to the soil surface, and then plow into the soil with a plough. This results in a limited mix of fertilizer and soil. The distribution of fertilizer is narrower than the application and matches the strip planting line. Looking from the vertical direction, pay attention to the depth and level of fertilizer application. The depth of basal fertilizer is different for different types of crops, such as 10-15 cm vegetables, 15-20 cm corn and 20 cm cotton. Stratified fertilization is mainly for phosphorus fertilizer, because of the small mobility of phosphate fertilizer, it is generally divided into two layers, the depth of the base fertilizer depth, shallow about 10 centimeters, if all the phosphorus concentrate in the deep, will cause seedling phosphorus deficiency symptoms. It depends on the characteristics of different fertilizers and the distribution characteristics of crop types and root systems. Special attention should be paid to the fact that excessive concentration of urea and high-nitrogen compound fertilizers will lead to burning roots and inhibiting seedlings. This will inevitably result in a reduction in crop production, waste of nutrients, and environmental pollution.
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