Auxin is indole-3-acetic acid, with the molecular formula C10H9NO2. It is the earliest hormone discovered to promote plant growth. The English word comes from the Greek word auxein (to grow). The pure product of indole-3-acetic acid is white crystal and is insoluble in water. Easily soluble in organic solvents such as ethanol and ether. It is easily oxidized and turns into rose red under light, and its physiological activity is also reduced. Indole-3-acetic acid in plants may be in a free state or in a bound (bound) state.

Difference in activity: 24-epibrassinolide is 97% active, while 28-homobrassinolide is 87% active. This indicates that 24-epibrassinolide has higher activity among chemically synthesized brassinolides.

Prohexadione calcium is a highly active plant growth regulator that can be used to control the growth and development of many crops and is often used in agricultural production.

How Brassinolide works
Brassinolide is a plant growth regulator that promotes plant growth and flowering and fruiting. Its principle of action is: Brassinolide can stimulate plant cell division and elongation, accelerate cell differentiation and tissue growth.