Brief Analysis of Herbicides MCPA SODIUM
What is MCPA SODIUM (3653-48-3)?
Sodium MCPA SODIUM is a phenoxyacetic acid-based selective systemic hormone-based herbicide that can destroy the conductive tissue of dicotyledonous plants, disrupting growth and development, twisting stems and leaves, and enlarging, thickening or cracking of stem bases. The volatility and speed of action are lower and slower than that of 2,4-D. MCPA SODIUM is very sensitive to the seedling stage of gramineous plants. The resistance gradually increases after the 3-4 leaf stage. It is strongest at the end of the tillering stage and is sensitive at the panicle differentiation stage. Sex rises again. The effect becomes significantly worse when the temperature is lower than 18°C, and the effect on unearthed weeds is not good. The usual dosage is 30 to 60 grams (active ingredient) per mu. Strictly prohibited for use on dicotyledonous crops.
Commonly used dosage forms include 13% water, 40% wettable powder, 56%, and 85% soluble powder.
Sodium MCPA SODIUM is often used as a herbicide in combination with other ingredients. If sodium MCPA SODIUM is inhaled, move the patient to fresh air; if skin contact occurs, take off contaminated clothing, rinse the skin thoroughly with soap and water, and seek medical attention if you feel uncomfortable; if contact with eyes, seek medical attention. Separate eyelids, rinse with running water or saline, and seek medical attention immediately; if ingested, rinse mouth immediately, do not induce vomiting, and seek medical attention immediately.
MCPA SODIUM (3653-48-3) Properties
The herbicide sodium MCPA SODIUM pure product is a white crystalline solid. Melting point 120℃. Soluble in organic solvents, ether 77%, ethanol 153%, toluene 6.2%, xylene 4.9%. Almost insoluble in water.
MCPA SODIUM (3653-48-3) Physical and chemical properties
CAS number: 3653-48-3
Chemical formula: CH3(Cl)C6H3OCH2COONa
Molecular mass: 222.6
Solubility: It has a pungent odor and is easily soluble in water. Its aqueous preparation is a reddish-brown or tan transparent liquid with a pH value of 9 to 11. The dry powder is easy to absorb moisture and agglomerate, but does not deteriorate.
Function of MCPA SODIUM (3653-48-3)
The herbicide sodium MCPA SODIUM is mainly used to treat stems and leaves after emergence. The herbicide penetrates the cuticle and cytoplasmic membrane, and is finally conducted to various parts, producing different effects on nucleic acid and protein synthesis in different parts. Inhibits nucleic acid metabolism and protein synthesis at the top of the plant, causing the growth point to stop growing and the young leaves to be unable to stretch until photosynthesis cannot proceed normally, thereby destroying the plant's normal ability to live, eventually leading to the death of the plant.
1. Sodium MCPA SODIUM is often used as a herbicide in combination with other ingredients. It can be mainly used to control annual weeds such as barnyardgrass, sedge, goosegrass, firefly, bermudagrass, sagittarius, special-shaped sedge, and sedge.
2 A 4 sodium chloride herbicides are used to destroy the conduction tissue of dicotyledonous plants, disturb the growth and development, twist the stems and leaves, swell and thicken the base of the stems, or crack. Poaceae plants are very sensitive to the drug when they are in the seedling stage, the resistance will gradually increase after the 3-4 leaf stage, the strongest is at the end of tillering stage, and the sensitivity will increase again at the young panicle differentiation stage. The effect of the drug will be relatively poor when the temperature is lower than 18°C, and it has no inhibitory effect on unearthed weeds.
3. Since dicotyledonous crops are more sensitive to sodium 2-methyl-4-chloride, it is necessary to avoid dicotyledonous crop fields when spraying, and to apply pesticides in windless weather to avoid phytotoxicity caused by pesticide drift.
4. When using sodium 2-methyl-4-chloride, it is also necessary to avoid the sensitive growth period, and at the same time control the dosage of the drug, otherwise the dosage is too large, or the concentration will be too high when spraying unevenly, which will cause phytotoxicity. Sodium 2M 4 Chloride has a certain antagonistic effect on some gramineous herbicides such as cyhalofop-ethyl and fenpyramid, so it cannot be mixed at will to avoid affecting the control effect of the pesticides.
Functional characteristics of MCPA SODIUM (3653-48-3)
The herbicide sodium MCPA SODIUM is a selective hormonal herbicide. Its mode of action and selectivity are the same as those of 2 and 4 drops. However, its volatility and action speed are lower and slower than 2,4-butyl ester EC, so it is safer than 2,4-D to be used in cold rice areas. Poaceae plants are very sensitive at the seedling stage, and the resistance gradually increases after the 3rd to 4th leaf stage, the strongest at the end of the tillering stage, and the sensitivity increases again when the young panicle differentiates, so it is advisable to apply the pesticide at the end of the tillering stage of rice. It is suitable for rice, wheat and other dryland crops to control three-edge grass, duckweed, Alisma, arrowroot and other broad-leaf weeds.
Preparation method of MCPA SODIUM (3653-48-3)
The herbicide sodium dimethyl tetrachloride is prepared from the reaction of o-cresol, water and liquid alkali. In addition, dissolve chloroacetic acid in water and slowly add liquid caustic soda at room temperature to form a sodium chloroacetate solution. Then slowly add the prepared aqueous solution of sodium chloroacetate into the sodium o-cresol solution for condensation reaction, after treatment, add hydrochloric acid for chlorination, cool, filter, and wash with water to obtain 2-methyl-4-chloro.The product is 2-methyl-4-chloride sodium salt, which is processed into aqueous solution.
MCPA SODIUM (3653-48-3) uses
Herbicide dimethyl tetrachloride sodium hormonal selective herbicide. It can destroy the metabolism of plants, causing them to deform, become swollen, crack, moldy and die. It is suitable for eliminating weeds in gramineous crops, such as small-grained grains, rice, peas, and lawns, and controlling a variety of annual and perennial dicotyledonous broad-leaf weeds and some monocotyledonous weeds. The dosage is 0.28-2. 25kg (active ingredient)/hm2 (1hm2=104m2). It is also effective in killing broadleaf grass and three-edge grass. This product has a great impact on broad-leaf crops such as cotton, soybeans, melons and vegetables, and will die after spraying. Cannot be mixed with acidic pesticides.
For use on small grains, rice, peas, lawns and non-cultivated areas for post-emergence control of annual or perennial broadleaf weeds
MCPA SODIUM (3653-48-3) safety
The oral LD50 is 700mg/kg in rats and 550mg/kg in mice. Rats fed with feed containing 100 mg/kg of the original drug for 7 months had mild kidney enlargement and no other adverse effects. The safe dosage for fish is 10mg/L. The oral LD50 of its sodium salt in male and female rats is 612 mg/kg and 962 mg/kg, and the transdermal LD50 in rabbits is >200 mg/kg.
MCPA SODIUM (3653-48-3) use
7-15 days after rice transplanting, at the cotyledon stage of barnyardgrass, use 100-120 grams of the active ingredient per mu, spread it on poisonous soil, irrigate the shallow water layer after application, and keep it for 3-4 days.
Wheat: From the tillering stage to before jointing, use 150-200 ml of 20% MCPA SODIUM water agent per mu and spray 40-50 kg of water to control most of the annual broad-leaved weeds.
Rice: Half a month after rice is planted, use 200-250 ml of 20% aqueous agent per acre and spray 50 kg of water to control most sedge weeds and broadleaf weeds.
Corn: After sowing corn and before seedlings, use 100 ml of 20% water agent per acre for soil treatment, or use 200 ml of 20% water agent per mu at the 4-5 leaf stage of corn, and spray 40 kg of water to prevent and control corn fields. Sedges and broadleaf weeds. During the corn growth period, directional spraying of 300 to 400 ml of 20% aqueous agent per acre also has a good control effect on larger sedges.
River channel clearing: It is advisable to remove river water hyacinths when the daily minimum temperature is above 15°C in May to June in the early stage of flood control. For water hyacinths with plant heights below 30 cm, 20% dimethicone per mu can be used on sunny days. Chlorine water solution 750ml plus soap powder 100-200g, or 20% MCPA SODIUM water solution 500ml plus 10% glyphosate water solution 1000ml plus soap powder 100-200g, mixed with 75kg of water to spray; For water hyacinths with a plant height of more than 30 cm, use the above herbicide mixed with 100 kg of water and spray it. After spraying the above herbicides, the higher the temperature, the faster the water hyacinth will die and the higher the mortality rate. The lower the temperature, the worse the effect. Generally, the whole plant dies 15 to 20 days after application.
MCPA SODIUM (3653-48-3) application
Sodium MCPA SODIUM is longer than other ingredients and used as a herbicide
1) Prepare a pesticide aqueous suspension containing a combination of MCPA SODIUM and bromoxynil octanoyl. It is mainly composed of dimethyl tetrachloride sodium salt, octanoyl bromoxynil, wetting and dispersing agent, tetramethylbenzene mixture 1500# and water, wherein the wetting and dispersing agent consists of castor oil polyether, epoxy ethylene propylene oxide block, fatty alcohol polyoxyethylene ether and calcium dodecylbenzenesulfonate. The purpose is to make the pesticide aqueous suspension of MCPA SODIUM and octanoyl bromoxynil composition have good stability, high suspension rate, and be less likely to crystallize, stratify and solidify after cold storage and hot storage. Compared with the existing technology, it is more environmentally friendly and safer to use. The compound complements the singleness and drug resistance of the two single agents. It has good adhesion on the plant surface and is resistant to rain erosion. Compared with other formulations, it has a wider herbicidal spectrum and is more resistant to pesticides. High efficiency, better and longer lasting effect.
2) Prepare a herbicide composition containing oxaziclozone and sodium MCPA SODIUM . It includes active ingredients oxatrione and sodium MCPA SODIUM , wherein the weight ratio between oxatrione and sodium MCPA SODIUM is 99:1 to 1:99, preferably 15:1 to 1:15. . The cumulative amount of oxaziclozone and sodium MCPA SODIUM is 0.1%-82% of the total weight of the composition, preferably 2%-20%. The herbicide composition of the present invention has reasonable components, and the control effect is better than the activity of each component when applied alone. It has a synergistic effect, expands the weed control spectrum, and can control Gramineae, Cyperaceae and broadleaves in rice fields with one application. Weeds, reduce the frequency of spraying, reduce control costs, slow down the emergence of weed resistance, good safety for crops, and meet the safety requirements of pesticide preparations.
3) Prepare a herbicide composition containing caprylic acid and sodium MCPA SODIUM . The main active ingredients of the herbicide composition include caprylic acid and sodium MCPA SODIUM . The dosage form of the herbicide composition of the present invention can be any dosage form permitted on pesticides. The herbicide composition of the present invention expands the herbicidal spectrum, has good effects on broadleaf grasses and grassy weeds, and exhibits good synergistic effects within a certain proportion range. The herbicidal effect of the composition is better than that of a single agent. There is a certain improvement, while reducing herbicide residues and reducing the potential threat of herbicides to the ecological environment.
4) Prepare a herbicidal composition containing pelargonic acid. The herbicidal composition contains the active ingredients pelargonic acid, glufosinate-ammonium, and sodium MCPA SODIUM ; in the composition, there is a balance between pelargonic acid, glufosinate-ammonium, and sodium MCPA SODIUM . The mass ratio is 5:1 to 30:1 to 5, and the preferred ratio is 5:5 to 20:1 to 5; in the composition, the mass of pelargonic acid, glufosinate and sodium dimethyl tetrachloride accounts for the combined It accounts for 5% to 80% of the total mass of the product, and the rest is pesticide auxiliaries. Its dosage form is one of dispersible oil suspensions, water-dispersible granules, and wettable powders; it can be used to control weeds in non-cultivated lands. The herbicidal composition of the present invention has a synergistic effect on barnyard grass and Amaranthus retroflexus, thereby reducing the amount of pesticides used.
5) Prepare a corn field herbicidal composition, which is characterized by including stable and effective sodium salt of dimethyl tetrachloride and nicosulfuron, and the weight portion of their effective components is 80:1 to 1:80. This composition combines the advantages of MCPA SODIUM and nicosulfuron in one. It can be sprayed inthe whole field at the 2-6 leaf stage of corn and the 2-5 leaf stage of weeds. It issafe for corn and the next crop and is effective for the next crop. The control effect of broadleaf weeds and sedge weeds is better and faster, and it also has a better control effect on gramineous weeds. It makes up for the shortcomings of the narrow herbicidal spectrum of traditional corn field herbicides and can control corn in one go. It can effectively eliminate various grass, broadleaf and sedge weeds in thefield, saving time and effort. When using, mix the two substances and prepare themimmediately for better effect.
How to use MCPA SODIUM (3653-48-3) in paddy field
Use time of sodium MCPA SODIUM in rice
Sodium dimethyl tetrachloride is sensitive to seedlings of gramineous crops such asrice. The resistance begins to increase after the 3-4 leaf stage. It reaches its strongest level from the tillering stage to the end. The sensitivity increases again at theyoung panicle differentiation stage.
Therefore, the application of rice pesticides should avoid the seedling stage and the panicle differentiation stage, and it is usually advisable to use it from the peak tillering stage to before jointing.
Sodium MCPA SODIUM dosage standard for rice
Generally, 50-100 grams of 56% sodium dimethyl tetrachloride is used per hectare of rice, and mixed with broad-leaf weeds such as duck tongue, sagittaria, rainflower, moshangcai, clove polygonum, or three-edge grass, water sedge, or Yingying. Spraying at the 2-3 leaf stage of cyperaceae weeds such as Lin Lin has good controleffect.
However, in recent years, with the widespread use of sodium MCPA SODIUM , the resistance to sodium MCPA SODIUM has increased in some areas. In order toexpand the herbicidal spectrum and improve the control effect, sodium MCPA SODIUM is currently used more than bentazone or propanil in production. Or mixed with drugs such as fentrazone.
It not only reduces the dosage of sodium MCPA SODIUM to avoid phytotoxicity, but also improves the weed control effect. However, because MCPA SODIUM is aselective hormone herbicide, it is prone to phytotoxicity, especially dicotyledonous crops.
Therefore, you should pay attention to the following points when using it:
1. Spraying sodium MCPA SODIUM herbicide should be used separately to avoid phytotoxicity due to unclean cleaning after application.
2. Sodium MCPA SODIUM is sensitive to dicotyledonous crops. When spraying, you should avoid dicotyledonous crop fields. At the same time, choose a windless weather to apply the pesticide to avoid pesticide drift and phytotoxicity.
3. When applying sodium dimethyl tetrachloride, care should be taken to avoid sensitive growth periods, and at the same time, the dosage should be controlled to avoid excessive dosage, or uneven spraying with too high a concentration, which may cause phytotoxicity.
4. Sodium MCPA SODIUM has an antagonistic effect on some grass herbicides such as cyhalofop-methyl and oxazofen. It should not be mixed at will to avoid affecting the control effect of the pesticide.
In short, sodium dimethyl tetrachloride should be used scientifically in an appropriate amount at a timely manner according to the local weed resistance, and mixed reasonably to prevent phytotoxicity and improve the control effect.
What is the difference between MCPA SODIUM (3653-48-3)and dimethyl tetrachloride ammonium salt?
The first synthesis method of 2,4-D was in 1941. The following year, the effectiveness of 2,4-D as a plant growth regulator and herbicide was one of the major agricultural inventions in the 1940s. Herbicides were officially recognized and Entering the organic era, 2,4-D developed rapidly, and similar varieties were developed one after another. Different groups were substituted on the benzene ring, and 2,4,5-D and 2-methyl-4-chloride were developed (2,4-D was developed in 1946). Methyl 4-chloride herbicide marked the birth of the first type of herbicides in organic synthesis - phenoxycarboxylic acid herbicides); by substituting side chain fatty acids, 2,4-D propionic acid and butyl ester were developed; In the synthesis of carboxylic acid group derivatives, we have developed salt varieties, 2,4-D sodium salt, potassium salt, ammonium salt, dimethylamine salt, etc. and ester varieties 2,4-D methyl ester, ethyl ester, Butyl ester etc.
2-Methyl-4-chloride is a phenoxycarboxylic acid selective herbicide with strong systemic conductivity. It is mainly used for post-emergence stem and leaf treatment. The agent penetrates the cuticle and cytoplasmic membrane, and is finally conducted to various parts. The parts have different effects on nucleic acid and protein synthesis. They inhibit nucleic acid metabolism and protein synthesis at the top of the plant, causing the growth point to stop growing. Young leaves cannot stretch until photosynthesis cannot proceed normally. The agent that is transmitted to the lower part of the plant makes the plant The synthesis of nucleic acids and proteins in stem tissue increases, which promotes abnormal cell division, enlarges root tips, and loses the ability to absorb nutrients, causing distortion and deformation of stems, clogging of sieve tubes, destruction of phloem, and obstruction of organic matter transportation, thus destroying the normal life of plants. ability, eventually leading to plant death.
2-methyl-4-chloride is widely used in wheat fields, corn fields, rice fields, urban lawns, and hemp crops to control annual or perennial broadleaf weeds and some sedges; it can be mixed with glyphosate to control resistant weeds and accelerate weed killing. The speed effect is obvious; there is also information that it can be used as a rice derooting agent to improve the efficiency of pulling out seedlings. Used for soil treatment, it also has a certain control effect on annual grasses and perennial weed sprouts propagated by seeds. It is widely used due to its low cost, fast speed, no residue and safety for subsequent crops. The main varieties that have been registered include: 2-methyl-4-chlorodimethylamine salt, 2-methyl-4-chloroisooctyl ester, Sodium methane chloride, ethyl 2methyl 4 chloride thioester, ethyl methyl 4 chloride, isopropylamine 2 methyl 4 chloride, ethyl methyl 4 chlorobutyrate. Most of the common varieties on the market are in the form of single agent or mixture. Among them, the single doses of sodium dimethyl tetrachloride are mostly 56% soluble powder and 13% aqueous agent, and there are also many combinations with glyphosate, bentazone, pentrazone, isoproturon, fluroxypyr, and dichloride. Mixtures made of benzosulfuron, atrazine, bensulfuron-methyl, bensulfuron-methyl, bromoxynil, chrysofuron, and atrazine. The developed dosage forms include wettable powder, aqueous agent, emulsifiable concentrate, and dry suspension. , five categories of soluble agents.
Compared with traditional sodium salt, 2-methyl-4-chlorodimethylamine salt shows four differences in actual use:
① It has a wider applicable temperature, high safety, is less likely to cause phytotoxicity at low temperatures, and has stable efficacy. Temperature factors affect the effectiveness and safety of herbicides. For example, 2-methyl-4-chloride sodium salt can easily cause phytotoxicity to crops when used at low temperatures (≤15°C). In the Huanghuai and Hai wheat areas, this type of species is used for weeding before winter and early spring. The risk is high and may cause phytotoxicity. The period of use is Reasons for improper control include excessive toxic impurities in herbicides. The impurity content of 2-methyl-4-chlorodimethylamine salt is only 1/20 of that of ordinary sodium salt varieties, and it is highly safe for crops even at low temperatures. The efficacy of general varieties is unstable when used at low temperatures. It is mostly recommended to be used above 18°C. The efficacy will be reduced below 19°C, which narrows the applicable period of this type of variety. The minimum suitable temperature for 2-methyl-4-chlorodimethylamine salt is 10°C. At this temperature, better results can be ensured. High temperature and strong light can promote the absorption and utilization of this type of species, but the volatilization of chemicals at high temperatures will harm surrounding dicotyledonous crops. Dimethylamine salt is not volatile, which avoids the impact of high temperature medication on surrounding sensitive crops.
② High activity and stable efficacy. Salt sprayed on crop leaves enters the plant and is converted into acid, causing poisoning. MCPA SODIUM varieties are processed into different forms. The herbicidal activity of the varieties in different forms is in the following order: ester>acid>salt. In the salt, amine salt>ammonium salt>sodium salt or potassium salt. 2-Methyl-4-chloride reacts with dimethylamine under specific conditions to obtain an amine salt, which improves the activity of the product and contributes to the stable efficacy of the drug. It also has a high control effect on old broadleaf grass.
③ Impurities are reduced, irritating odor is reduced and the metabolic pressure of crops is reduced. Traditional dimethyltetrachlorine varieties have the pungent smell of free phenol. High-concentration 2-methyl-4-chloride dimethylamine salt removes impurities to the greatest extent, reduces the pungent smell, reduces the metabolic pressure of crops, and reduces the risk of hidden phytotoxicity. Chances of production are increased.
④The sprayer is more clean. Compared with 2.4 drops and other varieties, the binding force between 2-methyl-4-chlorodimethylamine salt and the sprayer is weaker, which reduces the labor of cleaning spray equipment and reduces the herbicide damage caused by residual chemicals in spray equipment.
At the same time, some shortcomings of 2-methyl-4-chloramine salt have also been discovered in actual use. For example, the weed killing speed is better than that of sodium salt but slower than 2.4D varieties. Under long-term storage conditions, the acid return phenomenon is obvious, which will affect the preparation. Physical and chemical properties.
Factors that affect the weeding effect, in addition to the herbicide itself, factors such as water volume, spray quality, auxiliaries, air humidity, leaf surface condition, etc. will also affect the weeding effect. To achieve good weeding effect, you need to comprehensively consider all influencing factors. .
MCPA SODIUM (3653-48-3) precautions
1. Misuse of MCPA SODIUM in rice seedling fields will cause obvious symptoms of phytotoxicity in the 2-leaf and 1-heart stage of the seedlings. Old leaves turn yellow, stems fade, new leaves cannot be pulled out normally, and are rolled up into onion tubes and half unfolded. When peeling off the rolled leaves, you can see that the core leaves are twisted into rings, the stem base is swollen, the secondary roots of the seedlings are short and thick, and the plants are dwarfed and deformed. , dead in severe cases. After phytotoxicity occurs in the seedling field, the field should be drained and dried immediately, and additional quick-acting nitrogen fertilizer should be applied. The transplanting of seedlings should be postponed appropriately to alleviate symptoms and resume growth.
2. When using MCPA SODIUM spray to treat broad-leaf weeds in dicotyledonous crops such as onions and garlic, phytotoxicity is likely to occur, which will cause onion and garlic leaves to become distorted.
3. Improper use of MCPA SODIUM in the seedling stage of corn. Symptoms of phytotoxicity include leaf curling, and some becoming tube-shaped, tassels that are difficult to pull out, stems that become flat, fragile, and easy to break, leaves that are dark green, and growth on the ground. Short, stubby, misshapen supporting roots. In serious corn fields, the corn leaves turn yellow, dry, and have no ears. Even if the pesticide is sprayed according to the allowed amount within the appropriate period, if the pesticide liquid is sprayed on the heart leaves of the corn, it may cause phytotoxicity. When applying the pesticide on high-temperature days, more serious harm. Therefore, when applying dimethyl tetrachloride in corn fields, it should be used at the appropriate time and in the allowed amount. It is best to use flat sprinklers and spray quantitatively at low altitude to reduce phytotoxicity.
4. Cotton is extremely sensitive to MCPA SODIUM . The sprayer sprayed with MCPA SODIUM solution was used to spray the cotton field without thorough cleaning, which resulted in phytotoxicity. Injured cotton leaves will turn white and cannot carry out photosynthesis. If effective measures are not taken in time, the entire injured cotton field will be in danger of being scrapped, causing serious economic losses.
5. Rapeseed is very sensitive to MCPA SODIUM . The activity of this drug in the soil can last for 3 to 4 months. Do not use MCPA SODIUM to kill stubble before transplanting. If the transplanted rapeseed is slightly damaged by MCPA SODIUM , spraying plant growth regulators such as gibberellin will have a certain detoxification effect; however, spraying MCPA SODIUM before transplanting the rapeseed will have a certain detoxification effect on the transplanted rapeseed seedlings. Produced drug injury, it is difficult to use medicine to rescue. On the one hand, there is a lot of MCPA SODIUM remaining in the soil in the field, which will cause serious damage to rapeseed. On the other hand, the roots of rapeseed will continuously absorb MCPA SODIUM from the soil, making it difficult to control the use time and dosage of gibberellins. quantity. Therefore, for fields sprayed with MCPA SODIUM , it is best to plant crops that are not too sensitive to MCPA SODIUM , such as wheat.
The price of herbicide MCPA SODIUM (3653-48-3)
Under normal circumstances, the price of pesticide and herbicide sodium tetrachloride will be affected by raw materials, market environment, research and development costs, etc. If you want to know the latest price of MCPA SODIUM Sodium Pesticide Herbicide you need, please contact us to initiate an inquiry.
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