What plant growth regulators are used in cotton farming?
Cotton plant growth regulators are classified into categories such as stress resistance, rooting, inhibition and promotion of growth, drying and defoliation, and synergists. They are used both alone and in combination.
1. Maturation and defoliation regulators
(1)Ethephon:
mainly 40% aqueous solution. Ripening is an important role of Ethephon. It is a growth regulator that promotes plant maturity. After Ethephon enters the plant, it will release ethylene due to the pH value of the plant tissue, promote maturity, inhibit elongation growth, promote organ shedding and induce flower bud differentiation, promote germination, and promote the occurrence of adventitious roots. It is very stable in acidic media, and above pH 4, it is interpreted as releasing ethylene. Ethylene enters the plant through the leaves, bark, fruit or seeds of the plant, and then passes to the part where it works, releasing ethylene. Ethylene can play the physiological functions of the endogenous hormone ethylene, such as promoting cotton maturity and leaf shedding, dwarfing plants, changing the proportion of female flowers, and promoting the characteristics of early cracking and flowering of cotton bolls.
(2)Thidiazuron:
This product is a heterocyclic aromatic urea plant growth regulator, used as a defoliant in cotton cultivation. Currently, there are a variety of dosage forms on the market, including 38%, 12%, 50% and 80% dosage forms. It is absorbed by cotton leaves and can promote the formation of natural stratification and defoliation between stems, leaves and petioles. The defoliation effect depends on factors such as temperature and air humidity. The average temperature from 5 days before application to 15 days after application is 15 degrees to 21 degrees.
2. Cotton stress resistance regulator
(1)Gibberellic Acid GA3:
GA3 is an important plant growth regulator. Endogenous Gibberellic Acid GA3 is ubiquitous in plants and is one of the important hormones that promote plant growth and development. It is an antagonist of growth inhibitors such as Paclobutrazol and chloramphenicol. The drug can promote cell and stem elongation, leaf expansion, parthenocarpy, fruit growth, break seed dormancy, change the ratio of male and female flowers, affect flowering time, and reduce flower and fruit shedding. Exogenous Gibberellic Acid GA3 enters the plant, and it has the same physiological function as endogenous Gibberellic Acid GA3. Gibberellic Acid GA3 mainly enters the plant through leaves, twigs, flowers, seeds or fruits, and then conducts to the active growth parts. Gibberellic Acid GA3 has the effect of promoting cell division and growth, and reducing the shedding of buds and bells. Pure Gibberellic Acid GA3 products have low water solubility. It should be dissolved with a small amount of alcohol first, and then diluted before spraying.
(2) Naphthalene acetic acid (NAA)：
the main function is to prevent cotton buds and bolls from falling off, and it also has the function of drought resistance and waterlogging resistance. It has the functions of protecting flowers and fruits, improving fruit setting rate, promoting fruit hypertrophy and early maturity, and has a certain effect on controlling cotton growth and increasing yield. It is the main ingredient of rooting powder on the market.
3. Inhibition and growth factor regulator
(1） mepiquat chloride:
The main dosage form is 96%-98% original powder, which is characterized by inhibiting vegetative growth and promoting reproductive growth and root growth. Generally, according to the type of cotton field, the principle of full-process chemical control and small amount of multiple control is adopted. In the seedling stage, bud stage, full bud stage, before the first flower irrigation, flowering stage and boll stage, it can be regulated according to the strong or weak growth. It can inhibit cell elongation and inhibit gibberellin biosynthesis.
Promote the absorption of roots, stems and leaves, promote the synthesis of crop chlorophyll, inhibit the elongation of main stems and fruit branches, make plants compact, delay closure, prevent prosperity, improve field ventilation and light transmission, and help enhance photosynthesis; control crop wildness and reduce ineffective nutrient consumption; enhance crop root activity, develop root system, grow main roots, increase lateral roots, improve crop resistance, lodging resistance, drought and flood resistance; reasonably adjust and distribute the contradiction between vegetative growth and reproductive growth, promote reproductive growth, reduce flower and fruit shedding, early maturity, improve fruit quality, increase production and income.
(2）Sodium nitrophenolate:
also known as high-yield element, it has many functions, mainly 1.4%, 1.8% and 2% water. The characteristics of sodium nitrophenolate are to accelerate the rooting speed of cotton, promote growth, reproduction and fruiting. It is generally better to use it in the seedling and late stages of cotton, which can promote early growth and prevent late aging. Plant cell activators can quickly penetrate into plants, promote the flow of cell protoplasm, speed up the rooting of plants, and promote the developmental stages of rooting, growth, reproduction and fruiting of crops to varying degrees, especially to promote pollen tube elongation, help fertilization and fruiting. It can be used to promote cotton growth and development, early flowering, break dormancy, promote germination, prevent flower drop and bell, improve product quality, etc. Since it is different from plant hormones, it can be used at any time between the start of planting and harvesting. It can penetrate into the plant body, promote the flow of cell protoplasm, speed up the rooting of plants, and promote the developmental stages of rooting, growth, reproduction and fruiting of plants to varying degrees. The product can be treated by foliar spraying, seed soaking, seedbed perfusion and bud propagation.
(3)chloramphenicol:
It is mainly a 50% aqueous solution that can inhibit the biosynthesis of gibberellins in plants, prevent excessive plant growth, promote reproductive growth, and improve drought resistance and cold resistance. Although chlormequat mepiquat has the same effect, chlormequat mepiquat is prohibited in cotton fields with poor soil conditions. The mechanism of action of this product is to inhibit the biosynthesis of gibberellins in plants, and its action part is to inhibit the formation of calin, thereby hindering the biosynthesis of endogenous gibberellins. It is an antagonist of gibberellins. Its physiological function is to control plant growth, resist lodging, enhance photosynthesis, and improve stress resistance. Its physiological function is to control plant growth, resist lodging, enhance photosynthesis, improve stress resistance, improve quality, increase yield, and effectively regulate cotton growth.
(4) Uniconazole14-Hydroxylated:
This product can promote root development and improve root absorption capacity; control the nutritional growth of cotton, inhibit plant height, shorten internodes, compact plants, and thicken leaves; change the distribution direction of photosynthetic products, promote flower bud differentiation and fruit growth, promote multiple bolls, and reduce boll shedding.
(5) Brassinolide (BRs):
This product is a sterol plant growth regulator that can stimulate the inherent potential of plants, improve seed vitality, promote root development, regulate the robust growth of plants, improve fertilizer utilization, and enhance the reverse ability of crop resistance to increase fruiting rate. This product can be used as an auxiliary drug to alleviate drug damage or prevent diseases when mixed with other regulators or used alone.
(6) Abscisic Acid:
Abscisic Acid is a natural plant growth regulator that can promote the coordinated growth of plants, induce the expression of various stress resistance genes in plants, improve the growth quality of plants, and effectively enhance the resistance of plants to adversity. This product can enhance plant photosynthesis, promote root development and nutrient synthesis and accumulation, and has a certain effect on improving quality and increasing yield.
(7) Indole-3-butyric acid (IBA):
This product is an endogenous plant auxin. It can enter the plant body through the leaves, tender epidermis and seeds of the plant, and transfer to the functional parts with the nutrient flow. It can induce the differentiation of the plant root base, quickly open roots, accelerate the growth and development of the root system, greatly increase the number of capillary roots and the length of lateral roots, which is conducive to the formation of multiple and strong plant root groups, shorten the number of days for plant transplantation and seedlings, and significantly improve the survival rate and stress resistance of transplantation; promote tillering and strong seedlings; promote root renewal, strengthen plants, increase yields, and improve quality.
(8) DA-6 (Diethyl aminoethyl hexanoate):
This product has a regulating and promoting effect on cotton. It can increase the content of chlorophyll, protein, and nucleic acid in plants; increase photosynthetic rate, increase the activity of peroxidase and nitrate reductase; increase the metabolism of carbon and nitrogen in plants, enhance the absorption of water and fertilizer by plants, and regulate the water balance in plants, thereby improving the drought resistance and cold resistance of plants.
1. Maturation and defoliation regulators
(1)Ethephon:
mainly 40% aqueous solution. Ripening is an important role of Ethephon. It is a growth regulator that promotes plant maturity. After Ethephon enters the plant, it will release ethylene due to the pH value of the plant tissue, promote maturity, inhibit elongation growth, promote organ shedding and induce flower bud differentiation, promote germination, and promote the occurrence of adventitious roots. It is very stable in acidic media, and above pH 4, it is interpreted as releasing ethylene. Ethylene enters the plant through the leaves, bark, fruit or seeds of the plant, and then passes to the part where it works, releasing ethylene. Ethylene can play the physiological functions of the endogenous hormone ethylene, such as promoting cotton maturity and leaf shedding, dwarfing plants, changing the proportion of female flowers, and promoting the characteristics of early cracking and flowering of cotton bolls.
(2)Thidiazuron:
This product is a heterocyclic aromatic urea plant growth regulator, used as a defoliant in cotton cultivation. Currently, there are a variety of dosage forms on the market, including 38%, 12%, 50% and 80% dosage forms. It is absorbed by cotton leaves and can promote the formation of natural stratification and defoliation between stems, leaves and petioles. The defoliation effect depends on factors such as temperature and air humidity. The average temperature from 5 days before application to 15 days after application is 15 degrees to 21 degrees.
2. Cotton stress resistance regulator
(1)Gibberellic Acid GA3:
GA3 is an important plant growth regulator. Endogenous Gibberellic Acid GA3 is ubiquitous in plants and is one of the important hormones that promote plant growth and development. It is an antagonist of growth inhibitors such as Paclobutrazol and chloramphenicol. The drug can promote cell and stem elongation, leaf expansion, parthenocarpy, fruit growth, break seed dormancy, change the ratio of male and female flowers, affect flowering time, and reduce flower and fruit shedding. Exogenous Gibberellic Acid GA3 enters the plant, and it has the same physiological function as endogenous Gibberellic Acid GA3. Gibberellic Acid GA3 mainly enters the plant through leaves, twigs, flowers, seeds or fruits, and then conducts to the active growth parts. Gibberellic Acid GA3 has the effect of promoting cell division and growth, and reducing the shedding of buds and bells. Pure Gibberellic Acid GA3 products have low water solubility. It should be dissolved with a small amount of alcohol first, and then diluted before spraying.
(2) Naphthalene acetic acid (NAA)：
the main function is to prevent cotton buds and bolls from falling off, and it also has the function of drought resistance and waterlogging resistance. It has the functions of protecting flowers and fruits, improving fruit setting rate, promoting fruit hypertrophy and early maturity, and has a certain effect on controlling cotton growth and increasing yield. It is the main ingredient of rooting powder on the market.
3. Inhibition and growth factor regulator
(1） mepiquat chloride:
The main dosage form is 96%-98% original powder, which is characterized by inhibiting vegetative growth and promoting reproductive growth and root growth. Generally, according to the type of cotton field, the principle of full-process chemical control and small amount of multiple control is adopted. In the seedling stage, bud stage, full bud stage, before the first flower irrigation, flowering stage and boll stage, it can be regulated according to the strong or weak growth. It can inhibit cell elongation and inhibit gibberellin biosynthesis.
Promote the absorption of roots, stems and leaves, promote the synthesis of crop chlorophyll, inhibit the elongation of main stems and fruit branches, make plants compact, delay closure, prevent prosperity, improve field ventilation and light transmission, and help enhance photosynthesis; control crop wildness and reduce ineffective nutrient consumption; enhance crop root activity, develop root system, grow main roots, increase lateral roots, improve crop resistance, lodging resistance, drought and flood resistance; reasonably adjust and distribute the contradiction between vegetative growth and reproductive growth, promote reproductive growth, reduce flower and fruit shedding, early maturity, improve fruit quality, increase production and income.
(2）Sodium nitrophenolate:
also known as high-yield element, it has many functions, mainly 1.4%, 1.8% and 2% water. The characteristics of sodium nitrophenolate are to accelerate the rooting speed of cotton, promote growth, reproduction and fruiting. It is generally better to use it in the seedling and late stages of cotton, which can promote early growth and prevent late aging. Plant cell activators can quickly penetrate into plants, promote the flow of cell protoplasm, speed up the rooting of plants, and promote the developmental stages of rooting, growth, reproduction and fruiting of crops to varying degrees, especially to promote pollen tube elongation, help fertilization and fruiting. It can be used to promote cotton growth and development, early flowering, break dormancy, promote germination, prevent flower drop and bell, improve product quality, etc. Since it is different from plant hormones, it can be used at any time between the start of planting and harvesting. It can penetrate into the plant body, promote the flow of cell protoplasm, speed up the rooting of plants, and promote the developmental stages of rooting, growth, reproduction and fruiting of plants to varying degrees. The product can be treated by foliar spraying, seed soaking, seedbed perfusion and bud propagation.
(3)chloramphenicol:
It is mainly a 50% aqueous solution that can inhibit the biosynthesis of gibberellins in plants, prevent excessive plant growth, promote reproductive growth, and improve drought resistance and cold resistance. Although chlormequat mepiquat has the same effect, chlormequat mepiquat is prohibited in cotton fields with poor soil conditions. The mechanism of action of this product is to inhibit the biosynthesis of gibberellins in plants, and its action part is to inhibit the formation of calin, thereby hindering the biosynthesis of endogenous gibberellins. It is an antagonist of gibberellins. Its physiological function is to control plant growth, resist lodging, enhance photosynthesis, and improve stress resistance. Its physiological function is to control plant growth, resist lodging, enhance photosynthesis, improve stress resistance, improve quality, increase yield, and effectively regulate cotton growth.
(4) Uniconazole14-Hydroxylated:
This product can promote root development and improve root absorption capacity; control the nutritional growth of cotton, inhibit plant height, shorten internodes, compact plants, and thicken leaves; change the distribution direction of photosynthetic products, promote flower bud differentiation and fruit growth, promote multiple bolls, and reduce boll shedding.
(5) Brassinolide (BRs):
This product is a sterol plant growth regulator that can stimulate the inherent potential of plants, improve seed vitality, promote root development, regulate the robust growth of plants, improve fertilizer utilization, and enhance the reverse ability of crop resistance to increase fruiting rate. This product can be used as an auxiliary drug to alleviate drug damage or prevent diseases when mixed with other regulators or used alone.
(6) Abscisic Acid:
Abscisic Acid is a natural plant growth regulator that can promote the coordinated growth of plants, induce the expression of various stress resistance genes in plants, improve the growth quality of plants, and effectively enhance the resistance of plants to adversity. This product can enhance plant photosynthesis, promote root development and nutrient synthesis and accumulation, and has a certain effect on improving quality and increasing yield.
(7) Indole-3-butyric acid (IBA):
This product is an endogenous plant auxin. It can enter the plant body through the leaves, tender epidermis and seeds of the plant, and transfer to the functional parts with the nutrient flow. It can induce the differentiation of the plant root base, quickly open roots, accelerate the growth and development of the root system, greatly increase the number of capillary roots and the length of lateral roots, which is conducive to the formation of multiple and strong plant root groups, shorten the number of days for plant transplantation and seedlings, and significantly improve the survival rate and stress resistance of transplantation; promote tillering and strong seedlings; promote root renewal, strengthen plants, increase yields, and improve quality.
(8) DA-6 (Diethyl aminoethyl hexanoate):
This product has a regulating and promoting effect on cotton. It can increase the content of chlorophyll, protein, and nucleic acid in plants; increase photosynthetic rate, increase the activity of peroxidase and nitrate reductase; increase the metabolism of carbon and nitrogen in plants, enhance the absorption of water and fertilizer by plants, and regulate the water balance in plants, thereby improving the drought resistance and cold resistance of plants.
