1. Sulfonylureas 1. High activity, in grams per hectare. 2, killing grass spectrum, different varieties of weeding spectrum difference. 3, strong selectivity, high safety for crops, high efficiency for weeds. 4, easy to use, can be absorbed by the roots, stems, leaves of weeds, but also soil treatment. 5, the main target of the plant is acetolactate synthase, does not affect seed germination and emergence, weeds quickly stop growing after receiving the drug, but it takes a long time to die. 6, easy to develop acidic hydrolysis. 7. Safe for mammals. It is easy to decompose and not accumulate in the environment, and some varieties have a long-lasting effect in the soil, which may cause phytotoxicity to the crops. Thiasulfuron The agent can be quickly decomposed by soil microbes in the soil (30-60 days). The selective herbicide after the seedlings will die within 1-3 weeks after receiving the drug. It has poor effect on grass weeds and is ineffective against field spines. Soybean is safe under conditions of 20 to 10 degrees - 30 degrees / 20 degrees. When the temperature reaches 35/25 degrees, the safety of soybeans decreases. Used in wheat, corn, soybeans, peanuts. Bensulfuron The residual effect period is about 60 days, which is used for wheat to inhibit the growth of the bud sheath and root. The sensitive weeds die in 1-3 weeks. Chlorsulfuron (oxasulfuron) The residual effect period is more than 8 months. It is used for wheat to affect the crops. The wheat crops are quickly metabolized into harmless substances. The seeds will be seriously affected when they come into contact with the pesticides. Land plot. Methotrexate Long residual period for wheat Ethersulfuron Used in wheat, it can control annual broadleaf weeds and some grass weeds, and has better pre-emergence and post-emergence weeding effects on piglets. Do not spray the liquid on other crops. Bensulfuron Rice field, Honda, live field, wheat paddy field and live field can be applied before sowing and within 20 days after sowing, so that the application of the weeds in the early stage after sowing is good. Control the annual broadleaf weeds and sedges, keep the water layer 3-5cm for 3~4 days during application, the agent has little mobility in the soil, and the temperature and soil have little effect on it. Extending the water retention time is the key to improving the weeding effect. Long time, good effect. 5-7 days is appropriate, many days. Ethersulfuron Planting crops within 1-2 months after use, no adverse effects. When applying the medicine, close the inlet and outlet, and keep the water to ensure the imitation. This medicine is not suitable for use in leaky fields, otherwise it will cause the medicine to move downwards and concentrate the rice root area to cause phytotoxicity. Chlorsulfuron It has a long-lasting effect and is used as a selective pre-emergence bud treatment agent for soybeans. The sensitive weeds are chlorotic for 3-5 days and gradually die from 7 to 21 days. Soybeans can metabolize them into inactive substances. After sowing, 2 grams of active ingredient per acre before germination, after treatment, there will be different degrees of phytotoxicity, under normal circumstances can not be restored. It is not advisable to grow beets, rice, melons, vegetables, potatoes, cotton, etc. Sulfoxsulfuron With a long-lasting effect, it can remain basically grass-free for 1-2 years. It can not be used for planting crops within 3 years after application in forest land and non-cultivated land, and has certain phytotoxicity to broad-leaved tree seedlings. Pyrazosulfuron The effective period is 25-35 days, and it is mainly used for paddy field to be absorbed by roots, and it is rapidly transferred in weed plants to inhibit growth, and has little effect on rice. High security. It is most suitable for the early stage of weed seedlings. The transplanted field should be kept for more than 5 days. It should be avoided in the late bud stage and have phytotoxicity. Nicosulfuron It is used in corn systemic herbicides, which can be absorbed by weed stems, leaves and roots. It will die within 20-25 days. It has good application effect at the 4th leaf stage after weed buds. The drug has pre-emergence activity, but the ratio is higher than the bud. After the activity is low. Below the 2 leaf stage of corn, it is more sensitive than the 5 leaf stage, easy to phytotoxic (sweet corn and violent corn sensitive), no rain within 12 hours, and is beneficial to the drug. Amphetsulfuron Long residual period, rapeseed selective endocrine-conducting herbicide, 1-3 weeks necrosis symptoms. Gradually die. Rapeseed can metabolize the agent. It has poor control effect on wild oats and alfalfa. The live seeding and nursery fields were treated with soil after sowing or 1-3 days before sowing, and the transplanted fields were transplanted in rapeseed for 7-10 days. Brassica napus is safe and sensitive to 1-2 leaves. There is phytotoxicity in the back. Sulfonamide It is harmless to the crops that are normally rotated. It is used for corn systemic herbicides, which can be absorbed by weed stems, leaves and roots. It should be evenly sprayed. It is not possible to plant sensitive crops such as flax and rape in the second year after the medicine. Avoid application of organic phosphorus within 7 days after application. Insecticide (sweet corn, violent corn, sticky corn can not be used) Isosulfuron Short-lasting period, safe for post-crop crops (for lawn) Systemic herbicides can be absorbed by weed stems, leaves and roots. Under normal circumstances, fresh leaves are chlorosis for 20-30 days. death. Methyl disulfuron Sowing after 100 days, use with caution during intercropping, (for wheat fields). It is not suitable for wheat after jointing. It can not be flooded with wheat in 5 days after application. Otherwise, it will cause phytotoxicity. Weeds die within 15-30 days. Formamide Used in corn to control annual or perennial grass weeds and broadleaf weeds. Mainly through the absorption of stems and leaves, the sensitivity of crops and weeds is very different, and the proper amount of safener is added to the preparation. When the corn is used in the 2-4 leaf stage, the corn will temporarily appear white flowers or seedlings when the amount is large or the application is uneven. Generally, it can be restored to normal in 2-3 weeks, and has no effect on yield and quality. Cyclopropsulfuron It is used in rice, stable and safe. Rice can decompose the agent, which has stable efficacy and high safety. Because it is easily adsorbed by the soil, there is still a good effect in the short-term shortage of paddy fields in the northern water-soil field or after application. It has a certain inhibitory effect on tillering of rice, but has no effect on yield. Dibenzoyl 1. Some varieties are soil sealing treatment agents, and some are stem and leaf treatment agents. 2, the blocking treatment agent mainly kills the annual weed shoots, should be applied before the weeds sprout, the broadleaf effect is better than the grass weeds; stem and leaf treatment can prevent a variety of annual and perennial broadleaf weeds, but Perennial broadleaf weeds can only kill the aerial parts. It is not easy to move in the soil and has a moderate effect period. 3, the main contact strike effect on plants. 4, susceptible to phytotoxicity to crops, but only contact phytotoxicity, generally 5-10 days can be restored, does not affect production. Oxyfluorfen The half-life in the soil is about 30 days, and the duration of the rice field is 20-25 days. Selective contact-type germination herbicides mainly enter the plant through the coleoptile and mesoderm. The roots are rarely absorbed, and the herbicidal action is carried out under the condition of light. After being applied to the rice field, the soil surface is settled within 24 hours and is quickly soiled. Adsorption, no residual phytotoxicity to the sputum. For rice, it should be above 20cm, and should be more than 30 days old. It should be applied after the dew of the nursery. Keep the deep water layer inside 3-5. Acifluorfen The half-life of the soil is 30-60 days, which is used for the absorption of soybeans and peanuts through the stems and leaves, which promotes the closure of the pores and inhibits cell division. The drug is susceptible to phytotoxicity to crops and may appear brown spots after application. Spraying evenly, it is best to test first in the promotion, after 4 leaves of soybeans, the bean leaves cover weeds, the weeding effect is poor, and the phytotoxicity is aggravated, the maximum temperature is lower than 21 degrees or the soil temperature is lower than 15 degrees, easy to toxic . Fluoride It is easily decomposed by soil microbes and is used as a selective stem and leaf treatment agent for peanuts and soybeans. The 1-3 days sensitive broadleaf weeds have burn spots and gradually enlarge. After the whole plant is killed, there is not enough light to affect the efficacy. Play quickly. There are different degrees of drug spots on peanuts and soybeans, and the leaves grow normally in the later stage. Fomesafen The half-life is 6-12 months. It is used for peanut, soybean and mung bean before and after germination. In the early post-emergence period, we control the broadleaf weeds. The rain does not reduce the efficacy after 4 hours of treatment. After soaking, the soybean can be quickly degraded and the effective period Up to more than 1 month, due to the long residual period, it will not be passivated in the soil. Under normal application conditions, it has little effect on the sputum, and the large amount has phytotoxicity to the sputum. Carbofuran The shelf life is only 15 days in the soil and is easily degraded by microbial degradation. After a few hours, weeds have significant symptoms of drug exposure and are less affected by changes in ambient temperature. The phytotoxicity does not affect the yield. Third, urea 1. Mainly prevent annual weeds, especially for annual broadleaf weeds. 2, the principle is mainly to inhibit the Hill reaction of plant photosynthesis, light intensity can help the drug effect. 3, can not inhibit the seed germination, through the root absorption of the main body, upward conduction, accumulated in the leaves, the application effect before the weed buds. 4, mostly soil treatment agent, quickly adsorbed by the soil colloid after application, staying in the 0-3cm deep soil layer. 5. The herbicidal effect is closely related to the soil water content. Under normal circumstances, the herbicidal effect is high when the moisture is good. 6, mainly through soil biological degradation, the duration of the effect in the soil for several months to more than one year. The persistence period of the green mellon soil is about 70 days. It is used for the selection of endocrine-conducting herbicides for corn and wheat. It is mainly absorbed by the roots of weeds, and can also be absorbed by stems and leaves to inhibit the photosynthesis of weeds. The whole plant died after about 10 days, and it was used when weed 2 leaves 1 heart or 1 leaf 1 heart. Isoproturon It decomposes quickly in the soil, and the application period in autumn is up to 2-3 months. Used for wheat weeds to be absorbed by roots and leaves, more than 2-3 weeks after application. The safety of other crops is poor. Because of the short duration of use, it can only be applied during the Spring Festival. When the temperature is low to an average of 4 degrees per day, it has phytotoxicity to wheat seedlings. Li Gulong The half-life in soil is 38-67 days and the duration of effect is 4 months. It can be used as a soil treatment agent before the excavation of corn and wheat. After sowing, it can be used as a stem and leaf spray treatment before or after seedling and weeds 1-2 leaf stage. Areas with heavy sand and precipitation are not suitable for application. Diuron The period of validity is about 60 days. Can be pre-emergence treatment, many small sales seconds have a killing effect, wheat field is banned, cotton seedlings can not be applied after unearthed, peach trees are sensitive to it, pay attention. Sharon The application period can be up to 50 days. When applying the medicine, the field water should not be too deep, preferably 3-5cm. Fourth, carbamates 1. Due to different varieties, it can be absorbed by plant roots, coleoptiles and leaves, and has poor control effect on adult weeds. 2. The main action site is the meristem of the plant. The root tip of the victim crop is swollen, dwarfed, and malformed. 3. The main mechanism of action is to inhibit plant cell division, followed by inhibition of photosynthesis and oxidative phosphorylation. 4. Soil treatment varieties can be degraded by microorganisms in the soil, and the duration of eating in the soil is short, and it is 3-6 weeks in warm and moist soil. Chlorpyrifos The soil has a shelf life of 2-8 weeks, and the dry field is about 4 weeks old. It can be applied before and after the bud, and the effect is slow. The sensitive weeds gradually die in 1-2 weeks. When the average temperature is lower than 18 degrees, it affects the efficacy and is prone to phytotoxicity. Water leakage fields should not be applied. Not only can it be mixed with organophosphorus or carbamate insecticides, but it can not be applied before and after, otherwise it is easy to cause phytotoxicity to rice. Beet Ning The half-life in soil is less than 26 days. It is used for beet and spinach post-emergence stem and leaf herbicides. The application of soil is small. Immediately after spraying the drug, it should be sprayed. Beet It is used as a post-emergence stem and leaf treatment agent for weeds. Weed 2-4 leaves sensitive weeds have good effect. This medicine is very safe for crops. It can be used depending on weeds. It should be used now. Oatmeal For wheat, selective systemic herbicides, the agent can be absorbed by weed leaves, one week after the drug, stop growth and development, about one month later, some will resume growth, but it is obviously inhibited. Wild oats have poor efficacy after 4 leaves. The application of premature seedlings is small, the area of ​​the drug is small, and the effect is also poor. When spraying at low temperature (below 12 degrees), it is easy to cause phytotoxicity to wheat. Five, thiocarbamates 1, can prevent a variety of annual grass weeds, effective for some broad-leaved weeds 2. Most varieties are absorbed by weed roots and buds, which are important soil treatment agents. 3. Mainly inhibit the growth of plant meristems. The main symptoms of weeds are: abnormal leaves and growth malformation of grass weeds from coleoptile; in most cases, grass weeds sprout and emerge after application. And grow 1-2 pieces of true leaves and die 4. The selection principle mainly depends on the selectivity of the difference, the difference between absorption and conduction and its degradation in plants is also an important factor affecting selectivity. 5. Most of the varieties are aromatic liquids or low melting point solids, which are miscible with many organic solvents and have low water solubility. 6, generally more stable. Low toxicity Dingute The soil is easily decomposed by microorganisms and has a shelf life of 1-3 months. It is used as a selective soil treatment agent for corn. This product has strong volatility. It should be mixed immediately after the drug, which is safe for the later crops. Unearthed weeds are invalid. Hecaodan The half-life in the soil is 2-3 weeks under good ventilation conditions, and the anaerobic condition is 6-8 months. The drug can be quickly adsorbed by the soil, so it is small in leaching with water, generally distributed in 2 cm deep soil layer. Dechlorinated herbicide formed by soil microorganisms under anaerobic conditions can strongly inhibit rice growth. After the rice field medicine, a certain amount of water layer should be maintained. When the rice is in the seedling stage, the medicine cannot be applied during the needle-forming period, otherwise it is easy to be medicated. Not suitable for years. Pvc Roof Tile,Plastic Pvc Roof Tile,Pvc Roof Sheet,Pvc Roofing Sheet ZHENHAO BUILDING MATERIALS CO.,LTD , https://www.nbpvcroof.com