What causes soybean flower and pod drop?

1. Poor ventilation and light penetration. Sunlight is not only the main energy source for the production and accumulation of organic nutrients, but also the main factor that promotes rapid plant development and inhibits excessive vegetative growth. Good ventilation and light penetration in soybeans can make the climate between plants consistent with the climate above the plants, reduce humidity between plants, increase light and temperature, accelerate transpiration from the leaf area, and speed up the transport of nutrients.

2. Imbalanced nutrient supply. Plants on poor, thin soil drop more flowers and pods than those on fertile soil. Soybeans with excessive vegetative growth and shaded branches and leaves drop more flowers and pods than soybeans with normal growth and good ventilation and light penetration; flowers and pods formed later are more likely to drop than those formed earlier.

3. Unreasonable water supply

During the flowering and pod-setting stage of soybeans, high humidity, many cloudy days and frequent rain, and excessive soil moisture not only reduce the number of sunshine hours, but also lower the soil temperature, increase relative humidity, cause excessive vegetative growth, increase the degree of shading, and weaken photosynthesis, affecting the synthesis and transport of organic nutrients and increasing flower and pod drop.