Detailed Explanation of New Techniques for High-Quality, High-Yield Soybean Cultivation

Soybean is one of the crops with a relatively short growth period. Unfavorable conditions such as drought, waterlogging, lodging, and excessive vegetative growth during the growth period can all cause significant reductions in soybean yield. To develop soybean production, it is essential to take the promotion of new high-yield, high-quality, disease-resistant varieties as the foundation, and to center on assembling advanced scientific new technologies, following the path of increasing per-unit yield and benefits. In recent years, various regions have carried out a series of innovative studies on how to increase per-unit yield and benefits, achieving good results. The relevant high-quality and high-efficiency cultivation technical measures are now compiled and excerpted here and recommended to the broad community of farmers.

1. Seedling raising and transplanting. When soybean sowing time is affected by disasters, such as continuous drought or rainy weather that prevents sowing, raising seedlings and transplanting can shorten the vegetative growth time and ensure sufficient growth period in the soybean field. For summer soybean, seedlings can be raised 15 days before wheat harvest.

2. Root cutting cultivation. Soybean is a taproot crop with relatively deep penetration into the soil but few lateral roots. Cutting the soybean main root at the right time can promote the growth of lateral roots, increase nutrient absorption, and enhance the nitrogen-fixing capacity of rhizobia. Root cutting should be carried out 10-11 days after sowing. The method is to insert a thin iron shovel diagonally about 5 cm deep into the soil beneath the soybean seedling to cut the main root. It is strictly forbidden to displace the soybean seedling or damage the lateral roots.

3. Pinching. For soybean with a tendency toward excessive vegetative growth or late maturity due to excessive greenness, the terminal bud should be removed, which can promote branching, dwarf the plant and strengthen the stem, prevent lodging, and direct more photosynthetic products into flowers and pods, helping to increase flowers and preserve pods and raise yield. Generally, yield can be increased by more than 15%. Usually, 1-3 cm is removed from the top of the main stem at the early flowering stage or full flowering stage.

4. Chemical regulation. Lodging is a major problem in high-yield soybean fields. During soybean growth, adopting chemical regulation techniques can promote strong growth, suppress excessive vigor, increase flowers and preserve pods, and raise yield. The main methods of soybean chemical regulation are as follows:

(1) Spraying paclobutrazol. From soybean branching to early flowering, spray 20-30 kg of 100-200 mL/kg paclobutrazol solution per mu, which can dwarf soybean plants, prolong the functional period of leaves, help ventilation and light penetration in the soybean field, improve the microclimate, prevent lodging, and promote high yield. The concentration and number of applications should be determined according to soybean growth conditions.

(2) Spraying triiodobenzoic acid. At the flowering stage of soybean, spray a 100 mL/kg triiodobenzoic acid solution, then after an interval of 5-7 days spray a 200 mL/kg triiodobenzoic acid solution again, with 50 kg used each time per mu. This can inhibit the apical growth dominance of soybean plants, promote axillary bud development, increase branching, dwarf the plants, control excessive vigor and prevent lodging, increase flowering, reduce pod drop, and promote early maturity and increased yield.

(3) Spraying sodium bisulfite. At the early flowering stage and full flowering stage, spray 50 kg of 15-17% sodium bisulfite solution per mu once each time, which can reduce respiration intensity and decrease pod drop. During the soybean flowering and podding stage, use 50 kg of 20-30 mL/kg yield-increasing spirit solution, spraying once every week for 2 consecutive times. This can reduce pod drop by 10% and increase yield by 10-15%.

5. Supplementing trace elements. The trace element fertilizers required for soybean growth mainly include molybdenum, manganese, zinc, boron, magnesium, and others. These elements are present at very low levels in soybean plants, but their roles in various physiological functions are extremely important. Trace elements can promote normal soybean growth and development, increase soybean yield, and improve quality. Appropriately supplementing trace elements is an economical and effective method of increasing yield. For example, ammonium molybdate is a commonly used trace element for soybean. Applying molybdenum can increase yield by 5-20% (except on alluvial soil), with the most significant yield increase on albic soil, followed by black soil, sandy soil, and loess soil. However, excessive application can easily cause plant toxicity. In production, generally by soil testing and balanced fertilization, using seed coating agents containing trace elements for seed coating, or seed dressing with micro-fertilizers and foliar spraying, trace element deficiency symptoms can all be effectively prevented.

Preventing boron deficiency: apply about 1 kg of borax or boric acid solution per mu as base fertilizer, or spray 50 kg of 0.1-0.2% borax or boric acid solution at the soybean branching stage.

Preventing molybdenum deficiency: seed dressing with ammonium molybdate or foliar spraying can both prevent molybdenum deficiency. For example, 1 g of ammonium molybdate plus 40 g of water can be used to dress 1 kg of soybean seed, or at the soybean branching stage, 25-30 kg of 0.01-0.1% ammonium molybdate solution per mu can be used for foliar spraying.

Preventing zinc deficiency: first, zinc sulfate seed dressing, using 2-4 g per 1 kg of seed, and before dressing the seed, first dissolve the zinc sulfate with a small amount of water; second, basal application, applying zinc sulfate below or beside the seed, with 1 kg of zinc sulfate applied per mu of soybean field; third, foliar spraying, which can be carried out before the branching stage, using 50 kg of 0.01-0.05% zinc sulfate solution.

Preventing manganese deficiency: first, manganese sulfate seed dressing, using 4-8 kg per kg of seed; second, basal application, with manganese sulfate used at 2 kg per mu; third, foliar spraying. This can be carried out before the branching stage, using 50 kg of 0.05-0.1% manganese sulfate solution.

The above foliar spray amounts are all per mu.