Through the study of plant endogenous hormones, some phytohormone active analogues for agricultural production have also been artificially synthesized, which is a plant growth regulator. Plant growth regulators have more physiological and targeted effects than endogenous hormones. It is divided into the following major categories.
According to the role of plant growth regulators in agricultural production, plant growth regulators can be divided into five categories: plant growth promoters, plant growth inhibitors, plant growth retardants, preservatives and drought-resistant agents.