Full process fertilization plan for soybeans

Soybeans are native to China and are cultivated in various regions, as well as widely around the world. Soybean is one of the important grain crops in China, with a cultivation history of 5000 years. It was formerly known as Shu and is mainly produced in Northeast China, with Heilongjiang being the most famous. It is a crop with seeds rich in plant protein. Soybeans are most commonly used to make various soy products, extract soy oil, brew soy sauce, and extract protein.

1、 The law of soybean fertilizer requirement

(1) Classification of soybean growth stages

The life of soybeans involves processes such as seed germination, emergence, seedling growth, branching, flowering, podding, bulging, and maturation. It can be divided into 6 reproductive periods.

(2) The demand for fertilizer (NPK) throughout the entire growth period

The seedling stage of soybeans is a period of transition from seed nutrition to relying on their own root system to absorb nutrients. Sufficient phosphorus should be supplied and a small amount of nitrogen fertilizer should be applied. The flowering and pod setting period of soybeans is the most vigorous period for their nutritional and reproductive growth, as well as the period with the fastest nitrogen absorption. After the bulging stage, the root system's ability to absorb nutrients decreases, and the amount of absorption significantly decreases. Molybdenum and boron are essential trace elements for the growth and development of soybeans.

Soybean is a crop that requires a lot of fertilizer, as the formation of nutrients such as protein and fat requires a large amount of nutrients, especially nitrogen, phosphorus, and potassium. The fertilizer requirement of soybeans: For every 100kg of soybeans produced, it is necessary to absorb 6.5kg of pure nitrogen, 3.5kg of available phosphorus, and 3.2kg of available potassium, with a rough ratio of 2:1:1, which is higher than that of wheat and corn.

(3) The peak absorption and utilization of fertilizers (NPK) at various growth stages

1) The peak period of nitrogen absorption: the absorption of nitrogen during the seedling stage accounts for about 4% of the total amount; Flowering and pod setting period: 19%; From pod setting to grain filling stage: 70%, this stage is a critical period for soybean nutritional growth and reproductive growth, so it requires a large amount of fertilizer.

2) The peak period of phosphorus absorption: from the seedling stage to the early flowering stage, phosphorus absorption accounts for about 15% of the total amount; The flowering and pod setting period accounts for 60%.

3) The peak period of potassium absorption: from flowering to grain filling, the absorption of potassium accounts for 62% of the total amount, and during this period, the absorption of potassium is higher than that of nitrogen and phosphorus.

2、 Soybean fertilization technology (taking high-yield fields as an example)

(1) Basal fertilizer

Applying basal fertilizer is the foundation for high yield of soybeans, especially spring sown soybeans, which have a longer growth period. Basic fertilizer should include organic fertilizer, phosphorus fertilizer, and nitrogen fertilizer, and potassium fertilizer should be applied to potassium deficient plots. Adequate organic fertilizer can meet the needs of soybeans for various elements, especially potassium and trace elements. Suggested fertilization: Apply 2000-3000kg of decomposed farmyard manure per mu of base fertilizer, and 20-30kg of Stanley universal compound fertilizer (18-18-18, 16-16-16).

(2) Seed fertilizer

Fertilization should meet the nutrient requirements during the seedling stage. Due to the small number of roots during the seedling stage, the ability to absorb nutrients is weak, and sufficient nutrients should be supplied. Seed fertilizer can be furrowed and applied near the seeds to promote the formation of soybean rhizobia, increase the number of nodules, and fix nitrogen early and more. Rhizobial inoculants can be used for seed mixing, with 200-250g per acre of rhizobial inoculants used. The yield increase effect is significant. Suggested fertilization: When sowing, apply 5-10kg of Stanley universal compound fertilizer (same as base fertilizer) per mu, with a spacing of 6-8cm between seeds and fertilizer. Avoid direct contact between seeds and fertilizer.

(3) Topdressing

When applying sufficient base and seed fertilizers, soybean seedlings generally do not require topdressing. During the flowering and pod setting period, due to the vigorous growth of plants, a large amount of nutrients are needed. In order to meet the needs of soybean growth and development, increase flowers and pods, and improve soybean yield, topdressing should be carried out during this period. The timing should be controlled before flowering or the first flowering period. For fertile and strong growing plots, the amount of fertilizer should be applied less or not, and for plots with low fertility and weak growth, early and more fertilizer should be applied. Suggest fertilization; Apply 10-15kg of Stanley compound fertilizer (15-20-10) per mu, apply in furrows and strips, or spray 0.5% urea and 0.2% potassium dihydrogen phosphate solution on the leaves.

3、 Key management techniques

Sowing technology: 1) Select high-yield and disease resistant varieties; 2) Seed processing; 3) Timely and precise sowing; 4) Sowing with sufficient soil moisture; 5) Suitable sowing depth of 5 cm; 6) Post broadcast suppression.

Field management: 1) Check and replant seedlings, and determine seedlings through thinning; 2) Middle cultivation and soil cultivation; 3) Prevent lodging; 4) Prevent excessive growth; 5) Prevent premature aging; 6) Drought prevention; 7) Prevent diseases and pests.