Glyphosate is a commonly used organophosphorus herbicide, also known as glyphosate, glyphosate, roundup, and glyphosate. Discovered by D.D. Baird and others from the United States in 1971, it was developed and produced by Monsanto Company’s low-foaming surfactant isomer alcohol LF901. By the 1980s, it had become an important herbicide variety in the world. It is a biocidal herbicide that is absorbed into plants through stems and leaves and transmitted to body tissues, inhibiting the biosynthesis of amino acids, interfering with photosynthesis and causing them to die. It is effective against most weeds. The pure product is a non-volatile white solid that melts at approximately 230°C and decomposes. Its solubility in water is 1.2% at 25°C, and it is insoluble in general solvents. Generally, sodium salts and amine salts are not easily soluble in organic solvents, and its isopropylamine salt is completely dissolved in water. It is a systemic stem and leaf treatment agent and cannot be used for soil treatment. Non-flammable, non-explosive, stable storage at room temperature. It has a corrosive effect on medium carbon steel and galvanized iron (tinplate) containers. Low toxicity. Glyphosate is not easily absorbed by the gastrointestinal tract of animals, is quickly excreted by the kidneys and intestines without metabolism, and does not accumulate in the body. Under the test conditions, no teratogenic, mutagenic or carcinogenic effects were found on test animals. Mainly by inhibiting the activity of enolpyruvyl shikimate phosphate synthetase, it destroys the conversion of shikimate into phenylalanine, tyrosine, and tryptophan, thereby interfering with protein synthesis and leading to plant death. Glyphosate has extremely strong systemic conductivity and can be transmitted to underground rhizomes and tillers after being absorbed by stems and leaves. It is very destructive to the underground tissues of perennial deep-rooted weeds. After being put into the soil, it complexes with iron, aluminum and other ions and loses its activity. It has no killing effect on the seeds hidden in the soil.
[Toxicity] The acute oral LD50 in rats is 4320mg/kg. Mildly irritating to rabbit skin and eyes. Low toxicity to humans and animals. It does not accumulate in the body of animals, and no three effects were found within the test dose. It is non-toxic to bees and birds and safe to natural enemies. The fish toxicity is low, the TLm of trout and bluegill sunfish is greater than 1000mg/l, and they are basically harmless.
[Poisoning Mechanism] It can be absorbed through the skin and digestive tract. It has a slight irritating effect on the skin and strong irritation on the eyes. It is a low-toxic pesticide.
[Poisoning manifestations] Burning sensation on skin contact; After ingestion, stomach fever and nausea, followed by vomiting, diarrhea, and general discomfort; eye contact can cause conjunctiva inflammation.
【Poisoning Treatment】
Immediately move the patient away from the scene and remove contaminated clothing. Wash contaminated skin, hair, etc. with soap and water. For oral poisoning, use water or 2% sodium bicarbonate (trichlorfon should not be used) or 0.02% potassium permanganate solution (parathion, dimethoate, malathion should not be used) and gastric lavage repeatedly until it is cleared. For those who cannot quickly determine the type of pesticide they are taking, it is best to wash their stomach with water first. The temperature of the gastric lavage solution should be close to body temperature. During the gastric lavage process, attention should be paid to keeping the respiratory tract open to prevent aspiration. After the gastric lavage is completed, sodium sulfate should be administered for catharsis; eye contamination should be rinsed with saline.
Atropine sulfate is an effective antidote.
[Dosage form] Roundcup 41% aqueous solution; 10% glyphosate amine saline solution.
【Quality Standard】
Roundup 41% aqueous solution contains 41% glyphosate isopropylamine salt (equivalent to 350g/l glyphosate), surfactant, and water. Appearance: Amber transparent viscous liquid, density 1.17, boiling point greater than 100℃, non-flammable, non-explosive.
10% glyphosate ammonium salt solution contains 10% active ingredients (calculated as glyphosate), ammonium sulfate, water, etc. Appearance: light brown liquid, density 1.3, non-flammable, non-explosive.
[Mode of action]
Glyphosate is a systemic broad-spectrum herbicide. The process of action is spraying-yellowing-browning-withering. The medicine is absorbed into the body through the stems and leaves of the plant and transported to various parts of the body. Not only can it be transmitted to underground parts through stems and leaves, but it can also be transmitted between different tillers of the same plant, causing protein synthesis to be disturbed and leading to plant death. It is very destructive to the underground tissue of perennial deep-rooted weeds, but cannot be used for soil treatment.
【Applicable crops】
This product is suitable for weed control in orchards, mulberry orchards, tea gardens, rubber plantations, sugar cane gardens, vegetable gardens, cotton fields, field ridges, highways, railways, drainage and irrigation ditches, airports, oil depots, and factory open spaces, as well as sowing in no-till fields such as rapeseed. Weed beforehand.
【Objectives for prevention and control】
This product can control almost all annual or perennial weeds.
【How to use】
Glyphosate should be sprayed with about 25-30kg of water per acre before crop sowing and when weeds are growing vigorously in orchards, tea gardens, and field edges. Since various weeds have different sensitivities to glyphosate, the amount of glyphosate used is also different. Generally, crabgrass, bluegrass, green foxtail, barnyardgrass, goosegrass, milfoil, brogue, sycamore, and motherwort are controlled. , curly ear, chickweed, water chestnut, sageweed, springweed, perilla, mother-in-law, pigweed, spiny amaranth, patchouli, wood sorrel, pigweed, sedge, field pea, water pea. For grasses, etc., use 0.5-0.75kg of 10% glyphosate aqueous solution per acre; control Cyperus rotundus, Malanthus, plantain, small fly, paspalum, and mugwort., Commelina, annual, Houttuynia cordata, etc., use 0.75-1kg of 10% glyphosate aqueous solution per acre; control Imperata, reed, Polygonum, plover, Lobelia, Echinacea, Blackberry , snakeberry, scissors, wild onions, Senecio, bermudagrass, pinellia, coriander, aster, asteria, etc., use 1-1.5kg of 10% glyphosate per acre of solid saturated polyester resin. 1. Use in leisure land, field edges, and roads: Generally, when the weeds are basically out of sight and the weeds are in the 4-6 leaf stage, use 0.5-1kg of 10% glyphosate aqueous agent per acre, add 100ml of diesel and 20% of water. – About 30kg, spray the stems and leaves of weeds evenly in a directional manner. 2. Use in cotton fields: Before cotton is sown, when weeds have emerged in the field, use 0.5-0.75kg of 10% glyphosate aqueous solution per acre and add water (about 20-30kg), and spray it evenly and directionally on the stems and leaves of weeds. In cotton During the budding period, to control annual and perennial weeds, use 0.5-0.75kg of 10% glyphosate aqueous solution per acre, mixed with 20-30kg of water, and spray the grass stems and leaves evenly. When spraying, directional spraying should be used, and the nozzle should be depressed. A cover should be installed on the cotton leaves to prevent the mist from drifting to the cotton leaves and causing phytotoxicity. 3. Use in orchards, tea gardens, mulberry gardens, and forest trees: Generally during the peak period of weed occurrence, most weeds are in the 5-6 leaf stage. , use 1-1.5kg of 10% glyphosate aqueous solution per acre, or 0.5kg of 10% glyphosate aqueous solution, 100-150ml of diesel or 0.1% washing powder, add about 20-30kg of water, and spray directly on the stems and leaves of weeds When spraying, use directional spraying and do not spray the liquid on the leaves and young stems of fruit, tea, mulberry and forest.
【Notes】
1. Glyphosate is a biocidal herbicide. When applying the herbicide, care should be taken to prevent the liquid from drifting onto the stems and leaves of crops to avoid phytotoxicity.
2. The dosage of glyphosate per mu should be determined based on the sensitivity of the weeds to the pesticide. For general weeds, 500-1000ml per acre can be effectively controlled. For shrubs and perennial weeds, the concentration of pesticides should not be too high, with 1000 to 2000ml/acre being appropriate. Otherwise, the above-ground parts will die too quickly, which will cause the downward conduction of chemicals and will not kill the underground parts. It should be applied at an appropriate concentration and in divided doses.
3. Glyphosate is immediately passivated and loses activity when it comes into contact with soil, so it should be treated on stems and leaves. The appropriate application time is from when the weeds are in the vigorous growth stage to before flowering, when there is a larger leaf area that can be exposed to more pesticides.
4. When using glyphosate, you can add an appropriate amount of surfactants such as washing powder and diesel to improve the weeding effect and save the amount of medication. The amount of surfactant added is 0.2 to 0.5% of the spraying amount.
5. The effect of medication on warm and sunny days is better than that on low-temperature weather. Rainfall within 4 to 6 hours after application will reduce the efficacy of the medication, so additional spraying should be made as appropriate.
6. Glyphosate has a corrosive effect on galvanized containers made of metal such as steel, and can react chemically to produce hydrogen and easily cause fires. Therefore, plastic containers should be used when storing and using as much as possible.
7. When stored at low temperature, crystals will precipitate. When using, the container should be shaken thoroughly to redissolve the crystals to ensure the efficacy. 8. If Chinese medicine liquid splashes on your skin or eyes, wash it immediately with clean water repeatedly.
[Analysis method]
Liquid chromatography: Liquid chromatograph with adjustable wavelength detector, chromatographic column Partisil 10 SAX 250mm×4.6 (i. d.) mm stainless steel column. Detection wavelength UV=195nm, sensitivity 0.2AUFS, mobile phase buffer solution + methanol = 96+4, adjust to pH=2.1 with 85% phosphoric acid, flow rate 2ml/minute. Retention time 5.11 minutes.
Preparation of buffer solution: Take 0.6805g of potassium dihydrogen phosphate and dissolve it in 1L of water.
【Production method】
Pressure method: Use phosphorus trichloride and anhydrous formaldehyde to react under pressure. The product is hydrolyzed to obtain chloromethylphosphonic acid, which is then condensed with glycine to form glyphosate technical material.
Normal pressure method: react with chloroacetic acid and ammonia in the presence of calcium hydroxide to obtain iminodiacetic acid, which is then condensed with formaldehyde and phosphorus trichloride to form the intermediate bisglyphosate, and finally oxidized to obtain glyphosate technical material.
【Packaging, Storage and Transportation】
The raw powder is packed in lined plastic bags and woven bags, with a net weight of 25kg per bag; 50% wettable powder is available in three small packages of 0.25kg, 0.5kg and 1kg, plus a calcium plastic box, with a net weight of 20kg per box; 5% water The agent is packed in plastic barrels, with a net weight of 25kg per barrel; the isopropylamine salt water agent is packed in 200kg iron barrels lined with paint. 10% aqueous agent is available in 1kg and 25kg plastic barrels. Store in a cool and dry place. Do not mix with alkaline substances. Protect from shock and sun during transportation.
The above information is edited and compiled by Xiaogang of ChemicalBook.
