Brassinolide, also known as brassinolide, Yifengsu, and Tianfengsu, is a new type of sterol endogenous plant hormone, which can significantly increase plant vegetative growth and promote fertilization at very low concentrations. Brassinolide is recognized internationally as a highly effective, broad-spectrum, non-toxic plant growth regulator with the highest activity. It has the dual functions of dividing and extending plant cells, promoting the development of roots, enhancing photosynthesis, and increasing the chlorophyll content of crops. Promote the effective absorption of fertilizers by crops, assist the good growth of the disadvantaged parts of crops, promote roots and strong seedlings, preserve flowers and fruits; improve the resistance of crops to cold, drought, and salt-alkali resistance, and significantly reduce the occurrence of diseases; It can alleviate the occurrence of phytotoxicity. After the phytotoxicity occurs, it can be used to detoxify, so that the crop can quickly resume growth, and can eliminate disease spots; brassinolide can also significantly increase the yield and improve the quality of the crop.

The research on the application of brassinolide in agriculture has been carried out for nearly ten years, and the result has attracted widespread attention from all over the world.

1. Wheat: After being treated with brassinolide, there is a significant increase in yield. The brassinolide of 0.05～0.5mg/L can significantly promote the root system (including root length and root number) and plant height of wheat seed soaking for 24 hours. The effect of foliar spraying at this concentration during the tillering stage was obvious. Two weeks after the treatment, the chlorophyll content of the flag leaves was higher than that of the control, and the number of ears, ear weight, and 1000-grain weight increased significantly, and the yield was generally increased by 7% to 15%. The wheat seedlings treated with brassinolide are more resistant to winter low temperature. In addition, the functional leaves of the lower part of the plant grow well, which increases the resistance of wheat and reduces the chance of infection by diseases such as bacterial wilt.
2. Maize: Kernel abortion (i.e. baldness) at the top of the ear of corn is an important factor that affects the increase in yield. In corn fields, spraying the whole plant with 5ml of 0.01% brassinolide EC plus 50L of 0.01mg/L brassinolide with water can significantly reduce the abortion rate of the top kernel of the corn ear and increase the yield by about 20%. The effect of treatment before tasseling is better than spraying after spinning. The increase in the frequency of spraying corn ears can reduce the abortion rate, but the effect is not as good as spraying the whole plant. After the treatment, the leaf color of the corn plant becomes darker, the leaves become thicker, the dry leaf weight and chlorophyll content increase, and the photosynthesis rate increases. The activity of the grain at the top of the ear is increased (ie, the relative conductivity is decreased). In addition, the post-spinning treatment also has the effect of increasing the thousand-grain weight. Shanghai Institute of Plant Physiology, Chinese Academy of Sciences, Shanghai Institute of Materia Medica, and Japanese scientists conducted BR production increase experiments. The results show that the treatment of wheat with 0.01mg/L epibrassinolide can increase the seed setting rate and thousand-grain weight of wheat ears, thereby increasing the wheat by 10%. Treating corn ears with the same concentration can increase corn yield by 9.8% to 18.4%.