Analysis of Key Technical Points for Soybean Sowing

1. What key techniques should be mastered for soybean sowing?

1. Land selection. Soybean plots should not be planted continuously, otherwise pests and diseases are likely to occur. After the land is selected, it should be harrowed until the topsoil is loose and the surface is level.

2. Seed selection. Varieties suitable for planting in Tiandong include: Beijing bean, Yishan Liula, Guidou No. 1, Aijiao bean, Binyang Xiaoqing bean, local yellow soybean, etc. Each area can choose according to local conditions. Before sowing, select seeds of uniform size that are large and plump, and sun-dry the seeds.

3. Sowing. Early yellow soybean is sown from late February to mid-March, and late yellow soybean is sown between “Start of Autumn” and “End of Heat”.

4. Reasonable close planting. In principle, early-maturing varieties, lean land, and later sowing all require denser planting; otherwise, plant more sparsely. For dense planting, use 30,000-35,000 plants per mu; for sparse planting, use 20,000-30,000 plants per mu. Drilling or dibbling may be used. For dibbling, place 3-5 seeds per hole.

5. Base fertilizer. Generally, apply 500 kg of farmyard manure mixed with 30 kg of calcium magnesium phosphate fertilizer per mu.

6. Seeding rate. Generally 4-6 kg per mu.

2. How should field management of soybean be carried out well?

1. Check seedlings, fill gaps, and thin to a stand. After soybean seedlings emerge, check and fill gaps promptly. Thinning to a stand should be done when the first compound leaf appears. For dibbling, keep 2 plants per hole; for drilling with 40 cm row spacing, for a planned density of 25,000 plants, keep 15 seedlings per meter; for 15,000 plants, keep 9 per meter; for 35,000 plants, keep 24 per meter.

2. Scientific topdressing. Improper topdressing of soybean can cause excessive vegetative growth, lodging, and reduced yield. The principle of topdressing is to apply phosphorus and potassium fertilizer early and appropriate nitrogen fertilizer later. Generally, after thinning to a stand, apply 10 kg per mu of compound fertilizer with 45% content. At the late flowering stage (pod-setting stage), apply 5 kg of urea per mu. If the seedlings are growing vigorously, the first topdressing may be reduced or omitted.

3. Pest and disease control. The pod-setting stage of spring soybean occurs in hot, rainy weather, making soybean purple seed stain and downy mildew likely to occur. The main insect pest of spring soybean is the soybean pod borer, so inspection should be strengthened and control carried out promptly. Use 90% crystalline trichlorfon, or 50% fenitrothion combined with chemicals such as Duofeng, chlorothalonil, or Ridomil (use according to the instructions).