Plant growth regulators are synthetic or naturally extracted compounds from microorganisms that regulate the growth and development of plants, possessing chemical properties similar to plant hormones. Based on their roles in agricultural production, plant growth regulators can be classified into five categories:
Plant Growth Promoters: These regulators promote cell division, differentiation, and elongation in plants. They include auxins, gibberellins, cytokinins, and ethylene.
Plant Growth Inhibitors: These regulators inhibit plant growth and include abscisic acid, chlormequat chloride, and maleic hydrazide.
Plant Growth Retardants: These regulators slow down plant growth, such as paclobutrazol and uniconazole.
Preservatives: These regulators are primarily used to extend the shelf life of fruits and vegetables.
Anti-Drought Agents: These regulators enhance the drought resistance of plants.