Farmers' friends know that corn is one of the main food crops in China, and most of the regions in China have planted corn. Previously, Huinong.com introduced a lot of corn pest control, and today we will introduce a corn seedling. Introduction to the prevention and control of pests and diseases. 1 Corn seedling disease prevention 1.1 Corn seed blight Seedling blight in corn causes the plants of the corn seedlings to be short and slow to grow, and the leaves turn gray-green due to water loss. Subsequently, the leaf sheath is torn, and the leaves are gradually yellowed and dried from top to bottom. When the condition is more serious, the corn seedlings will be killed in large numbers, resulting in lack of seedlings and ridges. Seedling blight usually occurs and is prevalent in the low temperature and high humidity season. For the prevention and treatment of the disease, the seed can be treated by using 70% of the carbendazim WP 30g diluted with 500m L of water and mixing 10kg of seeds, which can effectively prevent the disease. If the onset of corn seedlings is found, 70% of the carbendazim can be used in the early stage of the disease, or 50% of the carbendazim WP 500 times, and the drug should be used once after 7 days. The use of foliar fertilizer in the use of the agent can promote root growth and make the corn seedlings more robust. 1.2 corn rough disease Corn rough disease can occur in the whole growth period of corn, but the damage is the most serious in the seedling stage. After the plant is infected, the symptoms usually appear in the 5~6 leaf stage, and the positive base of the heart leaf at the early stage of the disease The fine veins on both sides of the midrib have transparent, chlorotic spots with intermittent dotted lines, which gradually extend to the entire blade at the late stage of the disease. The plants with more serious onset shortened the internodes, and the leaves were stiff, wide and short, and thicker than the normal plants. The disease is mainly transmitted through the gray planthopper, and the incidence of corn planted in late spring is more serious. In the prevention and treatment of the disease, 30 g of imidacloprid wettable powder can be used, diluted with 500 ml of water, and 10 kg of seeds are mixed. And after the corn is planted, it is necessary to focus on the control of the gray planthopper before the seedling is fixed, and the imidacloprid wettable powder can be used for spraying prevention. 1.3 corn stem rot Corn stem rot is a disease that invades the roots and stem bases of corn after invading from the roots and spreads and spreads in the plants. When the condition is mild, the xylem of the roots and stems of the plants will turn brown, and in severe cases, the roots will be necrotic, causing the whole plant to die. In the prevention and treatment of the disease, the seed can be seeded with the corn bio-type seed coating agent, and generally 12.5% ​​of the diniconazole wettable powder 30-40 g of the seed dressing is used. For plots with serious onset of perennial disease, 46.1% copper hydroxide water dispersible granules can be used to spray the base at 1500 times. 2 Corn seedling pest control 2.1 underground pests The underground pests that harm corn mainly include tigers, crickets, crickets, etc., mainly harming the seeds and seedlings of corn, causing the seeds to fail to germinate normally or causing the death of seedlings, resulting in the phenomenon of seedlings lacking in the field. In severe cases, large pieces of seedlings in the field will be caused. If the seedlings are not replenished in time, the yield will drop. For the control of underground pests, it can be sown after seed dressing. Generally, 40% methyl isoflavin, 50% phoxim, 35% carbofuran, etc. can be used for seed dressing at 0.%~0.3% of seed weight. Using poison baits, the method of making poisonous cockroaches is to mix the sauteed cottonseed cake or wheat bran with crystal trichlorfon or toxic death chyme oil and then sprinkle it on the side of the corn seedlings in the evening; use poisonous soil, use 300~ per 667m2 500m L80% dichlorvos emulsifiable concentrate and 25kg fine soil are mixed well and then sown in the morning stalks next to the corn seedlings, or you can use 50% phoxim emulsifiable concentrate to water and then pour into the ground, the above methods can all be good. Control effect. 2.2 armyworm The armyworm is mainly harmful to the leaves of corn seedlings, and the leaves will be eaten into nicks. When the damage is serious, the whole leaves and leaves will be cleaned, resulting in a significant reduction in yield and even a failure. For the control of armyworms, the method of spreading poisonous soil can be used. 75~100g of 40% phoxim emulsifiable concentrate is used, mixed with 40~50kg of sand after watering, and then spread in the corn heart. 2.3 corn thrips The insect pest is more serious in the seedling stage, usually in the heart leaf. Adults and nymphs feed on the sap of the leaf, causing the plant to yellow and twist. There are patches of silver-gray in the leaves of the damaged plants. The leaves are yellow and some of the leaves are broken. In severe cases, the growth of the seedlings is affected. For the prevention and treatment of the disease, seed coating treatment may be used, or seed dressing may be carried out using 10% imidacloprid wettable powder. In the early stage of the disease, it can be controlled by using 10% imidacloprid wettable powder or 40% chlorpyrifos cream. 3 Corn seedling disease prevention Growing weeds in the field will compete with corn for water, water, and glory, affecting the growth of seedlings, and spreading a variety of pests and diseases. Therefore, doing a good job of weeding corn is very important for improving yield and quality. After the corn is planted, the herbicide can be sprayed with chemicals. In the 3~5 leaf stage after emergence, and the 2~4 leaf stage of weeds, the weeds can be sprayed with stems and leaves, and the chemical herbicide can use 4% nicosulfuron and 38% atrazine mixture, or Spraying the herbicide with the mesotrione suspension after watering. In the 8~9 leaf stage of the corn seedling, 20% paraquat water can be used. After watering, the grass is evenly sprayed. When using spray weeding, it is necessary to add protection to the nozzle. Cover, so as not to spray the liquid onto the corn heart leaves to cause phytotoxicity, affecting the growth of corn seedlings. In addition to the use of chemical herbicides for weeding, it is also necessary to carry out cultivating and weeding. The cultivating and weeding is a more traditional method of weeding. The weeds can be removed in time by manual or mechanical cultivating. This method is targeted and simple, not only can weed but also Provide good growth conditions for plants. In the process of cultivating and weeding, we must seize the favorable opportunity. In addition to being small, in addition to thorough, no seedlings should be left, so as to avoid causing troubles. The above is the whole content of the corn seedling disease and pest control technology, Hui Nongwang Xiaobian suggested that you also need to consider the actual situation at the same time! Integrated Roughness Profile Measuring Instrument
Roughness meter, also known as surface roughness meter, surface smoothness meter, surface roughness tester, roughness measurement meter, roughness tester, and other names. It has the characteristics of high measurement accuracy, wide measurement range, easy operation, portability, and stable operation. It can be widely used for the detection of various metal and non-metal processing surfaces. This instrument is a pocket instrument that integrates sensors and hosts, with handheld characteristics, making it more suitable for use in production sites. The exterior design is sturdy and durable, with significant resistance to electromagnetic interference, in line with current design trends.
The application fields of roughness meters include: Integrated Roughness Profile Measuring Instrument,High Speed Profilometer,Profilometer Measurement,Surface Profilometer Zhejiang dexun instrument technology co., ltd , https://www.dexunmeasuring.com
1. Mechanical processing and manufacturing industry, mainly metal processing and manufacturing. Roughness meters were originally developed to detect the surface roughness of machined parts. Especially, stylus type roughness measuring instruments are more suitable for detecting hard metal surfaces. For example, the automotive parts processing and manufacturing industry, the mechanical parts processing and manufacturing industry, and so on. As long as these processing and manufacturing industries involve the surface quality of workpieces, the detection application of roughness meters is essential.
2. In the non-metallic processing and manufacturing industry, with the progress and development of technology, more and more new materials are applied to processing processes, such as ceramics, plastics, polyethylene, etc. Some bearings are now made of special ceramic materials, and pump valves are made of polyethylene materials. These materials have a hard texture, and some applications can replace metal materials to make workpieces. During production and processing, their surface roughness also needs to be tested.
3. With the continuous strengthening and improvement of the technology and functions of roughness meters, as well as their in-depth promotion and application, more and more industries have been found to require roughness detection. In addition to mechanical processing and manufacturing, roughness evaluation is also required in the production and processing of power, communication, electronics, such as couplings on switches, integrated circuit semiconductors, and even stationery, tableware, and other products used in people's daily lives The surface roughness of human teeth needs to be tested.