Plant growth regulators have been used in China for nearly 50 years. Although the time is not very long, it has developed rapidly. At present, it has been widely used in field crops, cash crops, fruit trees, trees, vegetables, flowers and so on. Many research results have been widely used in production and achieved remarkable economic benefits, which has played a certain role in promoting agricultural production. One of the characteristics of plant growth regulators is that they can regulate the growth, development and metabolism of plants as long as they are used at very low concentrations. Some problems that are difficult to solve by cultivation measures can be solved. Such as breaking dormancy, regulating sex ratio, promoting flowering, chemical pruning, preventing shedding, etc.

There are two kinds of plant growth regulators: one is growth promoter, such as naphthylacetic acid to promote growth and rooting, gibberellin to break dormancy, and 6- benzylaminopurine to prevent aging; The other is growth inhibitor, such as chlormequat to prevent cotton and wheat from growing wildly, and bud inhibitor to prevent garlic and onion from sprouting. However, this classification is not absolute, because the same plant growth regulator can be used as a growth promoter at low concentration and a growth inhibitor at high concentration. For example, 2,4-D can promote rooting, growth, flower protection and fruit protection when treated at low concentration. At high concentration, it will inhibit plant growth; If the concentration is increased, dicotyledonous plants will be killed and have the effect of herbicide.

Proper and reasonable application of plant growth regulators can make plants develop in the direction people need, enhance the resistance of plants to pests and diseases, and eliminate weeds in the field. To sum up, the main functions of plant growth regulators can be divided into the following 2 1 aspects.

Main functions of plant growth regulators

The main functions of plant growth regulators are to promote germination of gibberellin, naphthylacetic acid, indoleacetic acid, indolebutyric acid, 2,4-d, 6- benzylaminopurine to promote growth of gibberellin, Zengchanling, Zengchansu, 6- benzylaminopurine to promote flowering of gibberellin, ethephon, naphthylacetic acid, 2,4-d to promote maturity of ethephon, ethyldiphosphonic acid, hydrazide and glyphosate. , plastic alcohol, chlorfenapyr, paclobutrazol, butyrhydrazide for thinning flowers and fruits, naphthylacetic acid, ethephon, carbaryl, inda, plastic alcohol for protecting flowers and fruits, 4- chlorophenoxyacetic acid, 2, 4-D, naphthylacetic acid, butyryl hydrazine, naphthoxyacetic acid with regulated ethephon, gibberellin with chemical ethephon killing effect, Ya Dan, methyl arsenate with improved quality, butyryl hydrazine, inda, glyphosate, gibberellin with enhanced resistance, paclobutrazol, S4-D, Ya Dan, 4- chlorophenoxyacetic acid, gibberellin defoliant ethephon and defoliant phosphorus.

Plant growth regulators enter plants and affect their growth, development and metabolism. These plant growth substances, including plant growth regulators and plant hormones, have different modes of action and complex mechanisms in regulating plant growth and development. Some can affect the permeability of cell membrane; Some can promote the release of bound substrates, thus accelerating the speed of enzymatic reaction; More through a series of physiological and biochemical reactions, the species and content of active enzymes in plants are finally adjusted, thus affecting metabolism and regulating plant growth and development.