1, germination period
Germination stage is the first growth stage of soybean, which refers to the period from sowing to spreading the first real leaf. It usually takes about 4 ~ 6 days, and the specific time varies with varieties, sowing, climate and management. For example, seeds can germinate 2-3 days before sowing.
2. Seedling stage
Seedling stage is the second growth stage of soybean, which refers to the period from the first true leaf of soybean seedling to flower bud. Generally, it takes about 20 to 25 days, accounting for 1/5 of the whole growth period. During this period, soybean mainly grows in nutrition, so it is necessary to provide enough nutrition to accelerate the growth of plants.
3. Flowering and pod setting period
Flower bud differentiation stage is the third growth stage of soybean, which refers to the period from flower bud to pod setting, usually about 30 ~ 40 days. During this period, vegetative growth and reproductive growth are carried out simultaneously. At this time, soybean needs a lot of nutrients, and nitrogen, phosphorus and potassium fertilizers are applied every 10 ~ 15 days.
4. Expansion stage
The seed filling stage is the fourth growth stage of soybean, which refers to the period from pod growth to pod expansion, generally about 15 ~ 20 days. During this period, soybean gradually changed from vegetative growth to reproductive growth, and seeds began to accumulate nutrients. After the grain filling stage, the water content of seeds is as high as 90%.
Step 5 mature
Maturity is the fifth growth stage of soybean, which refers to the period from complete expansion of pods to complete maturity, generally about 25 ~ 30 days. During this period, soybean mainly grew by reproduction, and the water content of seeds gradually decreased and showed the inherent physical form of varieties, with a slight noise when shaking pods.
Brief introduction of soybean
Soybean (scientific name: Glycine max? (Linn。 Merr) is a panicum miliaceum of Leguminosae, with a height of 30-90 cm. The protein content of soybean is 35% ~ 40%. Stems stout, erect, densely covered with brown bristles. Leaves usually 3-foliolate; Stipules and yellow pilose; Petiole 2-20 cm long; Leaflets broadly ovate, papery; Racemes are short, few flowers, long and many flowers.
Refer to the above content: Baidu Encyclopedia-Soybean