When it comes to plant growth regulators, you might say. Isn't this hormone? Yes, it is a hormone, but it is a synthetic substance with phytohormone activity, which can regulate the growth and development of plants.
Let's first understand what phytohormones are.
First of all, plant hormones
The so-called plant hormones, also known as endogenous hormones or natural hormones, are organic compounds produced by plants themselves, that is, they are innate substances of plants themselves and are not transferred by human will.
Plant hormones are transported from the produced parts or tissues to other organs. These substances are very few in plants, but they play a great role and are indispensable substances in plant life activities.
In order to obtain useful parts of fruits, flowers, stems and other plants, human beings cracked the code of this special substance and produced plant hormones through artificial synthesis, which were named "plant growth regulators".
So what is the role of plant growth regulators? What factors will affect its function? How to use it safely? What are the precautions? This article will answer them one by one.
Second, the role of plant growth regulators
1, which can promote growth.
Synthetic auxin, gibberellin, cytokinin and other substances can promote cell division and elongation, differentiation and the formation of new organs, and prevent fruit from falling off.
These substances mainly include 2.4-D, indoleacetic acid, indolebutyric acid, naphthylacetic acid, Zengchanling, gibberellin, 6-BA, PBA, zeatin and clofenurea.
2. Delay or inhibit action
Retarders and inhibitors in plant growth regulators are two different substances. Retarder is a substance that inhibits the growth rate of the top and lower parts of plants, slows down cell division and elongation, shortens the length of internodes and achieves dwarfing. It can promote flowering, but has little effect on leaf size and number, node number and tip advantage.
Such as chlormequat chloride, Bijiu, paclobutrazol, uniconazole, auxin, etc. , which belongs to the category of retarder.
However, unlike retarders, growth inhibitors can make plants lose their apical advantages, shrink their leaves and increase the number of side branches. Its main function is to inhibit cell division of plant apical meristem.
Such as plastic, Zhiyadan, triiodobenzoic acid, etc. Are growth inhibitors.
3, the role of promoting fruit ripening
Plants contain ethylene, whose function is to promote fruit ripening. In order to accelerate fruit ripening, people synthesized ethephon, which can promote fruit ripening as soon as possible after use, so as to obtain greater profits.
4, the role of defoliation and drying
For example, calcium cyanamide and doxorubicin can make the leaves of plants fall off as soon as possible and go into dormancy. For example, oxadiazon and pentachlorophenol can rapidly lose water in plants and promote cell death. Most of these substances are herbicides.
Third, the application method of plant growth regulators
Plant growth regulators can be used for seed soaking, root soaking, spraying, soil pouring and daubing. It depends on the situation and the variety of plant growth regulators.
Fourth, the factors affecting plant growth regulators
There are many factors that affect the function of plant growth regulators, such as environmental conditions such as temperature, humidity and light, as well as plant cultivation measures such as water, fertilizer and light, otherwise the stamina will be insufficient and premature aging will not be achieved. There are also the growth and development of plants, the concentration of growth regulators and the use methods, which will affect the role of regulators.
Verb (abbreviation of verb) Precautions in using regulator
This is the focus of this article. I am going to knock on the blackboard. Ha, pay attention!
First, master the concentration, usage and location.
For example, ethephon can promote the growth of main vines and open female flowers early, but the use period must be paid attention to, and it must be in 4? Six tablets are used in the true leaf stage, which is easy to be harmed in the early stage. Shall we all use 2.4? It can prevent falling flowers and fruits and improve the fruit setting rate, but it will cause phytotoxicity if it is used on eggplant, tomato and other eggplant vegetables. Therefore, we should pay attention to the concentration, and adjust it according to the growth and temperature of plants when using it.
Second, it is better to rely on others than on yourself. The concentration should be determined after testing, and then promoted in a large area.
The effect of plant growth regulator is closely related to its concentration. Too low concentration can not achieve the expected effect, but too high concentration will be great, which will destroy the normal physiological activities of plants and even cause phytotoxicity.
Third, pay attention to the climatic conditions when using.
At present, most of us spray regulators on leaves. If the temperature is too low, the absorption speed of leaves is too slow, and the effect is not good. But if the temperature is too high, the water in the liquid medicine will evaporate quickly, leaving only pure medicine on the leaves, which will destroy the leaves. Therefore, when spraying the regulator under dry conditions, the concentration should be reduced, on the contrary, the concentration should be increased in rainy season. Spraying time should be before 10 in the morning, preferably after 4 pm.
In windy weather and rainy days, it is not suitable to take medicine for the time being, but it can be supplemented or sprayed again after taking medicine for 4 hours. If you water it, don't water it too much, so as not to lose the medicine and affect its efficacy.
Fourth, pay attention to the use method and the parts used.
When using the regulator, it should be used according to the purpose. For example, 2.4-D is mainly used to prevent falling flowers and fruits, so it must be applied to flowers to inhibit the formation of fruit stalk falling, which will cause phytotoxicity to young leaves.
Fifth, don't mix them casually.
Some plant growth regulators can be mixed or mixed with other substances, but some are not suitable for mixing. We must fully understand the enhancement or resistance between mixed substances before we can decide whether it is possible or not, and we must not mix them at will.
Well, that's all for this article. If you have any questions, please leave a message for discussion. The next article will talk about the phytotoxicity of plant growth regulators. If you want to see it, please stay and I'll adjust the topic.