As an important nutritional organ of soybean, the root system directly determines the absorption and transformation capacity of soybean, and also plays a vital role in the growth and development of soybean.
The minimum temperature for soybean germination is 10~12℃, the optimum temperature is 18~20℃, the soil moisture content is 20%~24%, and the seedlings can generally emerge in 10 days.
However, in high-latitude areas, low temperatures often prolong the germination process of spring-sown soybeans, delay germination, and reduce the germination rate. At the same time, low temperatures will increase the susceptibility of soybean seedlings, reduce the survival of seedlings, and cause uneven populations.
Plant growth regulators can effectively regulate the endogenous hormone system of soybeans, enhance their cold resistance, and accelerate the occurrence of lateral root primordia, increase the number of lateral root primordia, shorten the occurrence time of lateral root primordia, and improve the emergence rate.
Commonly used plant growth regulators in production are:
1. Sodium nitrophenolate (ATONIK)
Use 1.8% ATONIK to prepare 6000 times liquid, soak soybean seeds for 3 hours, have a good root promotion effect, improve the quality of seedlings
2. Gibberellic acid
Use 3.5mg/L gibberellin solution to soak seeds, effectively accelerate the initial germination speed of spring-sown soybeans at 10~15℃, significantly accelerate the growth rate of young roots, and increase the fresh weight and dry weight of young roots. Especially at 10℃, the promotion effect is greater than 15℃, while there is no obvious promotion effect at 25℃.
3. Triacontanol
Triacontanol milk powder can be used for seed soaking. Soaking seeds with a concentration of 0.5mg/L liquid for 4 hours can improve the germination rate and germination potential, increase three-kernel pods, reduce single-kernel pods, and increase the number of beans.
