Pesticide is a commonly used chemical substance in agricultural production, which is used to prevent and control diseases, insects and other harmful organisms that endanger agriculture and forestry and to purposefully regulate plant growth.
According to the source of raw materials, it can be divided into inorganic pesticides, organic pesticides and biological pesticides.
Among them, biological pesticides are divided into plant-derived pesticides, animal-derived pesticides and microbial pesticides, and hormone pesticides belong to this category.
Hormone drugs are mostly plant growth regulators, which are synthetic substances with plant hormone characteristics and can regulate plant growth and development.
What are the hormone drugs? First of all, auxin
It is synthetic, and its function is similar to auxin, gibberellin, cytokinin and so on. It can promote the division and elongation of plant cells, the differentiation and formation of new organs, prevent fruit from falling off and induce the occurrence of adventitious roots.
Such as 2.4-D, indoleacetic acid, indolebutyric acid, naphthylacetic acid, naphthoxyacetic acid, bufalin, bufalin and tetrandrine.
Second, gibberellin.
Promote cell division and elongation, promote stem and leaf growth, increase plant height, increase yield, break dormancy, promote germination, improve seed germination rate and germination speed, promote seed setting and induce parthenocarpy.
The common one is 920, which is gibberellin.
Third, cytokinin.
Cytokinins mainly expand the volume of plant cells without elongation, inhibit senescence, preserve freshness, induce flower differentiation and promote lateral bud growth.
Such as kinetin, 6- benzylaminopurine, etc.
Fourthly, abscisic acid
It can inhibit the division and elongation of plant cells, promote the formation of abscission layer, cause the abscission of leaves, fruits, flowers and other organs, promote aging and maturity, promote the dormancy of seeds and buds, inhibit germination and improve drought resistance.
Fifth, ethylene and ethylene releasing agent.
Ethylene is a natural or endogenous substance from plants, which can promote fruit ripening, inhibit growth, shorten and thicken stems, and promote senescence and shedding.
Ethylene releasing agent is a synthetic compound that releases ethylene, such as ethephon, which can be absorbed by plant stems, leaves, flowers and fruits, and then gradually releases ethylene. It is mainly used for fruit ripening, promoting leaf abscission, and controlling the sex of crops such as flowers and melons.
Ethephon is stable at pH below 4. When the pH value in plants reaches 5-6, it will slowly degrade and release ethylene gas.
Sixth, brassinolide.
Its main function is to promote growth, protect flowers and fruits, promote the expansion of flowers and fruits, improve the cold and disease resistance of crops, delay senescence and improve quality.
Such as brassinolide.
Seventh, growth inhibitors and retarders
Inhibitors and retarders have different functions. Inhibitors mainly inhibit cell division in apical meristem, resulting in the loss of apical dominance, the increase of lateral buds and the decrease of leaves.
It cannot be reversed by gibberellin, that is to say, once the drug is damaged by excessive inhibitor, it is ineffective to save it with gibberellin.
Such as Yiyadan, triiodobenzoic acid, plastic (chloromethyl Dan), glyphosate, etc.
Retarders mainly prevent the synthesis of gibberellin in plants, inhibit the cell division and elongation growth in the lower part of the top of the stem, lead to slower plant growth, shorter and shorter internodes, and promote flowering, but have relatively no effect on the size, number, number of nodes and top advantage of leaves.
Such as chlormequat chloride D, chlormequat chloride, paclobutrazol, etc.
Eighth, other plant growth regulators
Such as triacontanol, sodium bisulfite and compound potassium nitrate.
To sum up, no matter what kind of regulator we are familiar with, there are mainly chlormequat chloride, aminoethyl ester, 6- benzylamino adenine, 2.4-D, gibberellin, paclobutrazol, sodium nitrophenolate, chlorfenuron, choline chloride, naphthylacetic acid, triacontanol, sodium cyclamate, uniconazole, ethephon, chlorpyrifos and chlorfenuron.
These hormonal drugs can be dipped, sprayed, smeared and poured. However, it should be noted that attention should be paid to ring conditions, cultivation measures, plant growth and development, use period, concentration and methods. Otherwise, it is easy to cause phytotoxicity.