Cotton plant growth regulators are classified into categories such as stress resistance, rooting, inhibition and promotion of growth, drying and defoliation, and synergists. They are used both alone and in combination.

Thidiazuron (TDZ) is a compound with special plant growth regulating effects.Thidiazuron (TDZ) is used for cotton defoliation and ripening. It is absorbed through cotton leaves, affecting the three main plant hormones in plants - ethylene, auxin and cytokinin, promoting the formation of natural abscission layer between stems and petioles of cotton, leading to cotton leaf fall.

The first is to promote crop growth, such as Gibberellic Acid GA3, Naphthalene acetic acid (NAA), etc. can stimulate the growth of plant stems and leaves, early bolting and flowering, promote the development of crop seeds, roots, stems, etc., stimulate fruit growth, and increase fruiting rate.
The second is to inhibit crop growth, such as Chlormequat Chloride (CCC), Paclobutrazol (Paclo), etc., which can inhibit crop leggy growth, promote tillering and root development, resist lodging and salt-alkali resistance, etc.

Biostimulant has many effects on crop growth. Although it is not a fertilizer or pesticide, it has certain functions to promote the effectiveness of fertilizers or pesticides. It plays an important role in promoting crop growth and enhancing the ability of crops to resist adverse stress. The target of Biostimulant is the crop itself. A small amount of application can achieve the effect of promoting plant growth and development, and this promotion effect is difficult to achieve with traditional nutrients.