There are many ways to use fungicides , and each method of use is designed according to the law of disease occurrence. The common methods of use are: spraying the crops on the ground, disinfecting the soil and disinfecting the inoculum.
For the field crop spraying, the factors affecting the field defense effect of the fungicide are not only the three aspects of the agent, the environment, and the crop, but the application technology of the fungicide is higher than the application technology of the insecticide and the herbicide, especially It is necessary to fully understand the law of the occurrence and development of diseases, because the occurrence and development of diseases are not as clear as pests and grasses. There are two points to note about spraying crops in the field: first, the type and concentration of the agent. The choice of the type of the drug depends on the type of disease, so it is necessary to make a correct diagnosis of the type of disease before it can be prescribed. For example, rice blast can be selected from rice glutinous rice, rice glutinous rice, tricyclazole, wheat powdery mildew, rust, triazolol, triadimefon, etc., and peanut leaf spot should be selected from methyl thiophanate. However, it should also be noted that if the same disease occurs on different crops, sometimes the same agent cannot be used. For example, Bordeaux mixture can prevent downy mildew, but it is easy to cause phytotoxicity to cabbage, so it is not suitable for controlling cabbage downy mildew. After the type of the drug is selected, an appropriate application concentration is selected according to the type of the crop and the growth period, the type of the bactericide, the dosage form, and the environmental conditions.
The general pesticide instruction manual has recommended concentrations, which can be used according to the instructions, but it is best to apply according to the concentration used by the local plant protection technical department based on the efficacy test. In dry or hot summers, the concentration should be reduced to avoid phytotoxicity. Secondly, when using the fungicide, pay attention to the period of use and the number of uses. The key to mastering the spraying period is to master the law of disease occurrence and development, to predict the forecast of disease occurrence, or to predict the crop disease according to the local plant protection department. It is predicted to prepare for spraying the fungicide. Under normal circumstances, the spraying of fungicides is carried out in the early stage of the disease, such as rice blast, especially in high temperature weather, rice blast develops rapidly, and should be sprayed immediately. However, the development of peanut leaf spot disease is relatively slow. Do not spray easily when the disease is on, and it is not possible to spray before the onset of the disease, but to start spraying when a certain development trend is formed after the onset of the disease. The climatic conditions are conducive to the rapid development of the disease, and should be sprayed immediately. Sometimes, in order to control the disease, it is necessary to spray the medicine when it is drizzling. The spraying period is determined by the law of disease development, and the growth period of the crop is also taken into consideration. Many diseases occur in connection with a certain growth stage of the crop. In addition, attention should also be paid to the tolerance of the fungicides during the growth period of the crops to prevent phytotoxicity. The occurrence and development of plant diseases often takes a while, and it is difficult to solve the problem once by spraying the fungicide. It often needs to be sprayed several times. The number of sprays is mainly determined by the reinfection of the bacteria, the residual period of the fungicide, as well as climatic conditions, light, temperature and rainfall.
Seedling disinfection. For soaking seeds, use emulsions and solutions. Do not use suspensions. Wet powders should not be used for soaking seeds. The key to soaking seeds is the concentration of the liquid and the time of soaking. Improper handling can result in poor sterilization or phytotoxicity. Other factors such as temperature, seed type, and the location of the pathogen also affect the soaking effect. Under normal circumstances, after the seed type, temperature, and drug type are determined, the concentration of the drug and the soaking time can be coordinated, and the high concentration can appropriately prolong the soaking time. If the pathogen is deep or the seed coat is hard, the soaking time can be extended appropriately. The high temperature can shorten the soaking time. Seed dressing and powder must be dry when seed dressing, otherwise it will cause uneven seed dressing, produce phytotoxicity, and affect the germination rate of seeds. The dosage of the powder generally accounts for 0.2%~0.5% of the weight of the seed. When the seed is mixed, the medicament and the seed are divided into 3~4 batches, and then the seed dressing container is appropriately rotated to make it evenly mixed. After the emergence of systemic fungicides, a new method of seed dressing--wet mixing method has emerged in recent years. That is, the powder is wetted with a small amount of water, and then seeded, or the dried powder is mixed on the wet seeds, so that the powder adheres to the surface of the seed. After being sown, the medicament is slowly dissolved and absorbed into the plant to conduct upward.
Soil-borne diseases such as cotton wilt and cucumber wilt may be controlled by soil disinfection, in addition to being controlled by soaking or seed dressing. Soil disinfection should first select the appropriate fungicide according to the type of disease, and then select the appropriate soil treatment method according to the physical and chemical properties of the drug and the soil structure and properties. The watering method is suitable for the water-soluble bactericide. After adjusting the medicinal agent to the appropriate concentration, watering about 5~10 kg of liquid per square meter of ground can be used. When the soil is dry, a lower concentration of the liquid can be used, and the watering volume is appropriately increased. When the soil is wet, high-concentration and small-volume watering can be used. The bactericide with higher vapor pressure can be applied by plowing or furrow, that is, the powder or liquid is evenly sprinkled into the bottom of the first plough, and the soil is covered by the soil of the second plough. This method is not suitable. For heavy soil, the powder or liquid can be applied to the surface of the soil, and then the soil is buried in the soil.
Stainless Steel Shower Head,Air Injection Shower Head,Stainless Shower Head,Solid Stainless Steel Shower Head
Moon Shower Sanitaryware Co.,Ltd , https://www.moonshowerglobal.com