Joke Collection Website - Bulletin headlines - What kind of fertilizer is needed to grow soybeans?

What kind of fertilizer is needed to grow soybeans?

For soybean planting, nitrogen, phosphorus, and potassium should be used together, and nitrogen fertilizer should be applied sparingly.

1. Principles of fertilization

1. Improve fertilization technology. Fertilization of soybeans should be a combination of nitrogen, phosphorus and potassium. Nitrogen fertilizer should be applied sparingly and top dressing should focus on the early flowering period;

2. Pay attention to the lack of medium and trace elements such as calcium, sulfur and molybdenum, and can take measures such as foliar fertilization and micro-fertilizer seed dressing to solve the problem;

3. Promote mixed seed dressing with rhizobia agents , to improve the nodulation efficiency; pay attention to the problem of soybean heavy cropping and its relationship with fertilization.

4. For plots where heavy stubble is serious and unavoidable, the amount of nitrogen fertilizer application can be appropriately increased or a general-purpose compound fertilizer can be used to make up for the reduced nitrogen fixation capacity caused by heavy soybean stubble. However, the amount of nitrogen applied should not be too much, otherwise it will inhibit nitrogen fixation.

5. Strengthen comprehensive management and promote the application of organic fertilizers in combination with deep plowing and land preparation. Spring soybeans can be plowed deeply (about 20 cm) after the previous autumn harvest and sown in spring; summer soybeans can be plowed deeply before wheat planting and shallow plowing before beans are planted; Northeast spring soybeans and summer soybeans in the Huang-Huai-Hai region should be planted according to the local climate and soil. and mechanized conditions, and adopt different management modes of tillage, sowing, fertilization, etc. Unless layered fertilization is carried out by mechanization, an appropriate amount of nitrogen fertilizer should be applied in the early flowering stage; cultivating soil and weeding should be carried out in the seedling stage; proper irrigation should be carried out in the flowering and pod stage in case of drought; through Comprehensive measures such as agricultural control, biological control and chemical control are used to prevent and control downy mildew, viral diseases, bean hornworms, heartworms, bridge-building insects, aphids, dodder and other diseases, insect pests and weeds.

2. Characteristics of fertilizer requirements

1. The flowering and pod stage is the peak period of nutrient absorption. The flowering and pod stage is not only the peak period of dry matter accumulation, but also the peak period of nitrogen, phosphorus and potassium nutrient absorption. stage, for example, from the end of branching to the early stage of seeding, the cumulative amounts of dry matter, nitrogen (N), and phosphorus (P2O5) account for 58.7 and 60.8 of the total in the entire growth period respectively, so the first flowering is the critical period for top dressing.

2. Soybeans require a large amount of nitrogen, but the root nodules can fix nitrogen. Soybeans require a large amount of nitrogen, which is 4.5 to 5 times the phosphorus requirement; because the root nodules can fix nitrogen, they can meet 40 to 60% of their own needs. Therefore, less nitrogen fertilizer can be applied. But it cannot be ignored because the root nodules lack the ability to fix nitrogen before they grow. It should be noted that the amount of nitrogen applied should not be too large, otherwise it will inhibit biological nitrogen fixation.

3. Soybeans require a large amount of calcium, like sulfur, and are sensitive to molybdenum deficiency. The calcium content in their grains is more than 10 times that of wheat grains. Soybeans like sulfur, so potassium sulfate is used. Compared with potassium chloride, it can improve the quality of soybeans; molybdenum helps the formation of root nodules and improves nitrogen fixation. Soybeans are sensitive to molybdenum deficiency. Therefore, attention should be paid to the lack of trace elements such as calcium, sulfur, and molybdenum and corrective fertilization.

4. Intercropping with grass crops can prevent iron deficiency. Taking the intercropping of legumes and corn as an example, soybean root nodules can fix nitrogen and can also supply corn in addition to self-use. The root systems of corn and other grass crops can secrete maggenic acid and have a strong ability to activate insoluble iron in the soil. Not only are they not deficient in iron, soybeans whose roots are weak in activating iron in the soil will also benefit.

5. Avoid heavy cropping. Heavy cropping inhibits nitrogen fixation in root nodules and causes abnormal absorption of soil nutrients. Coupled with the autotoxicity of root exudates (i.e., allelopathy), it is easy for soybeans to Nutrient deficiencies and infection with pests and diseases. These problems are particularly prominent in soybean-producing areas such as Heilongjiang Province.