What pests and diseases will corn encounter during the planting process? How to control corn pests a

Introduction: Corn is very common in daily life, it is not only nutritious and delicious, but also rich in nutrients needed by the human body, and it is very friendly to some children. Many farmers will grow corn, and the state will also provide a certain amount of subsidies every year.

In the countryside, there are many farmers who have planted large areas of corn, although it is said to be relatively high-yielding, but corn is very susceptible to pests and diseases. <>

When planting corn, we must remove the corn body that has appeared pests and diseases in a large area to eliminate and reduce the initial bacterial infection. If the corn is eroded by this disease, then it will reduce the yield, which will directly affect the economic income of the farmer, and when planting, we can take certain precautions, in addition to applying nitrogen fertilizer, which can reduce the probability of the disease. If it is already sick, you can use chlorothalonil and carbendazim spray for prevention and control.

Corn rust is one of the very common diseases in corn planting, if you want to prevent this disease, we can choose anti-epidemic varieties, apply compost in the planting process, increase phosphorus and potassium fertilizer, avoid excessive fertilization, through these methods to improve the disease resistance of corn. If corn rust has already appeared, we can spray 800 times with 97% sodium dirust stock solution and 50% antibacterial special wettable powder on corn. <>

Corn is very susceptible to bugs, such as the armyworm, which is one of the most common bugs in corn production. You can choose to plant corn in some higher places, and reasonable honey planting, timely removal of weeds in the field, if there are pests and diseases, use certain methods to deal with them. In addition to corn armyworm, corn borer is also one of the most common pests, which, if present, will cause a loss of about 15% of the annual yield.

It is easier to appear is large spot disease, brown spot disease, rough shrinkage disease, seedling blight, and sheath blight, etc., first of all, we should pay attention to the environmental temperature of planting, and we should also do a good job in the prevention and control of pests and diseases, we must use pesticides and fertilizers in time, and we must use insecticides and fungicides, and do a good job of ventilation.

These pests and diseases that will appear are cataplexy, large spot disease, seedling blight, and virus disease. If we want to prevent these pests and diseases, then we must strengthen the management of corn and prevent and control corn.

In the process of corn planting, it is often encountered that the larvae of the noctuidae pests are noctuidae, often feed on the leaves, eat up the leaves, and must be prevented, the specific control method is to spray insecticides first, and then spray baking soda solution regularly every 10 days, which can be controlled.

Common pests and diseases of corn in planting include large spot disease, small spot disease, bacterial wilt, iron beetle, borer, etc. Increase the application of organic fertilizer to improve the disease resistance of plants and control corn insect pests.

Corn is not an insecticide or fungicide, but foliar spraying of corn can enhance the resistance of corn to pests and diseases.

<> disease occurs in the whole process of corn growth and development, the seedling stage appears from the base of the heart leaf green spotted flower leaves, gradually extends to the whole leaf, the mesophyll loses green and turns yellow, forming obvious yellow-green stripes, the disease is serious, the diseased plant dies, and the corn can not be headed.

Control methods: Choose disease-resistant varieties for planting, and use early pesticides to eliminate aphids and planthoppers before migrating to corn fields. It can be sprayed with 40% oxidized happy fruit 3000 times liquid or 50% anti-aphid wettable powder, which can play a good role in control.

Corn roughness disease. Corn roughness disease generally does not occur in the whole field, and there are many diseased plants in places with many weeds such as roadsides and ditches. The occurrence of corn roughness disease is caused by the poisoning of gray planthoppers, once it is poisonous, lifelong poison, persistent poisoning, corn can be harmed when one leaf is one heart, the earlier the corn is damaged, the more serious the corn damage, 5-6 leaves begin to show symptoms, and once the symptoms are manifested, there is basically no cure.

10% imidacloprid wettable powder 20 g, % cyanocyanide or cyhalothrin 25 ml, 48% chlorpyrifos EC 25 ml, 25% parametrix EC 30 ml, % avermectin 25 ml, control the number of planthoppers. Or spray pesticides and insects before and after sowing near the emergence of seedlings, spray 10 imidacloprid 30 grams per mu plus 100 ml of 5 bacterial poison clear, both insecticide, spray again every 5 days, and use 2 times 3 times in a row to control the disease.

People get sick, and crops get sick. Once crops become "sick", it will cause reduced yields, reduced quality, and even no harvest. Today, I will introduce the more common corn diseases, hoping to help farmers prevent them.

Symptoms: The ear infection is infected from the tip of the ear downward, the ear grains are coal-stained, and there is a black mold layer on the surface of the grains and between the grains. The diseased grains are dry rot, and the grains are powdered by twisting them by hand.

Yellow leaf disease, yellow stem disease, rotten fruit disease, this kind of disease will have a lot of damage to corn, and the problem is also very big, especially terrible.

Prone to corn spot, corn root rot, corn spot, corn thrips, corn armyworm disease, corn powdery mildew, corn borer disease, and so on.

Corn large spot disease.

Corn large spot disease, also known as stripe disease, coal streak disease, leaf blight disease, leaf spot disease, etc., is the main leaf disease of corn, which occurs in all parts of China, and the damage is serious. It mainly harms leaves, and can also harm leaf sheaths and bracts in severe cases. Generally, it starts from the bottom leaf and gradually expands upward, and in severe cases, it can spread throughout the whole plant, but there are also cases of disease from the middle and upper leaves.

Large nucleated lesions are formed on the infected leaves, which are water-stained blue-gray or gray-green small spots at the beginning of the field, and after expansion, they are dark brown, light brown or gray diamond-shaped or long spindle-shaped large spots at the edges, generally 5-10 cm long, and there is an obvious black-brown mold layer on the lesions when wet, and the lesions are combined with longitudinal cracks when the lesions are severe, and the leaves die.

First, give priority to the selection of high-quality varieties.

Corn is prone to problems such as pests and diseases in the late growth stage, and growers must choose corn varieties that are resistant to viruses and pests. At present, corn diseases and insect pests can be roughly divided into semi-respiratory, semi-respiratory, rust, smut and so on. When selecting seeds, it should be based on varieties with strong antibodies, such as Woyu No. 3.

2. Physical prevention and control.

The use of physical control technology can reduce the harm of toxic substances left in corn to humans and animals, and maintain soil fertility. The main methods are: the use of strong ultraviolet light sterilization.

However, this method is limited to large farms and has a high technical cost. Lights trap and kill insects. Some corn pests love light, and growers can use light to trap pests.

3. Chemoprophylaxis.

Growers use chemical pesticides to eliminate plant pests and diseases in corn, achieve rapid insecticide, and prevent the invasion of plant pests and diseases. However, it is difficult for planters to scientifically grasp the application rate of chemical pesticides, and it is easy to burn seedlings or ears. For example, growers can use dichlorvos to control insects, diluting dichlorvos by 50% in relative proportions and spraying ears of corn can effectively kill insects.

Or use a sprayer to spray the disinfectant evenly on the corn and pest surface.

Fourth, cycle management.

In order to prevent the breeding of corn diseases and pests, growers can take the following measures in advance: (1) Basal fertilizer should be reasonably applied before corn planting to improve soil fattening capacity and provide a good soil foundation for the subsequent growth of corn. However, growers should always pay attention to the corn growth cycle and rules, and apply fertilizer on time.

For example, growers can effectively stretch ears of corn by applying nitrogen fertilizer. (2) Reasonable watering. Corn is a crop that requires a lot of water, and growers need to pay attention to the problem of corn water shortage at all times and irrigate corn reasonably.

Adjust the amount of corn irrigation in time according to the growth of corn and local climate change, so as to ensure the basic water requirement of corn. Otherwise, pollination will be delayed in the later stages of corn growth, directly reducing corn yield. (3) Observe the situation of corn diseases and pests, and prevent diseases and pests in advance.

Growers must keep a detailed record of the daily growth of the corn. Do a good job of prevention in each growth link of corn, continuously accumulate experience in corn pest control, and deduce the specific onset time and main symptoms to achieve the purpose of prevention.

Corn is currently one of the main grains, but also one of the world's three major cultivated crops, the economic value of corn is relatively high, in addition to being used as food, its straw can also be used for thermal power generation and so on. Pests and diseases have always been the main factor that threatens corn and even the whole food crop, so the control of corn pests and diseases is of great significance to ensure the yield of corn crops. Technically speaking, the main methods of control are agricultural, biological, physical and chemical methods, and the types of corn diseases and insect pests mainly include large spot disease, silk smut, smut, corn borer and aphid.

The growth process of corn is obviously affected by natural conditions such as temperature, humidity and light, and it is also more susceptible to disease or pest erosion. According to statistics, more than 10 kinds of corn diseases and insect pests have been found in China, among them, large spot disease, silk smut and powdery mildew are the main diseases, and corn borer and aphids are the main insect pests. When corn is affected by different kinds of pests and diseases, it exhibits different states.

For example, large spot disease can wilt the leaves of corn, while corn borer can cause many holes in the stalk of corn.

First, choose the right corn variety, pay attention to its disease resistance, and try to choose a mix of varieties, once the disease occurs, it is good to reduce losses; second, crop rotation and stubble; Thirdly, avoid the peak period of the outbreak of large spot disease, choose the right time to sow seeds, do a good job of weeding and fertilization, and remove 2 bottom leaves from each plant to reduce the humidity of the farmland; Fourth, spraying pesticides, if it is found that corn has signs of large spot disease, a certain concentration of pesticides can be sprayed, and the varieties of pesticides are carbendazim wettable powder, thiophanate-methyl wettable powder, chlorothalonil wettable powder and benzomyl emulsifiable concentrate. <>

The best way is to choose plants that are resistant to this disease, and try to plant as many varieties as possible to avoid major losses. Crop rotation is also an essential part. There is also a more effective way to prevent and control this disease, which is to uproot the plants that are prone to silk smut or have been infected with silk smut, and sweep the surrounding soil with pesticides to prevent the disease from falling into the land.

The main drugs for the prevention and treatment of this disease are Xiuning wettable powder, pentachloronitrobenzene and so on. Of course, this disease can also be effectively prevented and treated by seed coatings.

When planting, we must choose the soil is relatively fertile and broad, and we must use farmhouse fertilizer when fertilizing, do not use the fertilizer bought outside, and often water the plants, but also to prevent the occurrence of pests and diseases, if there is a situation of small insects, then we must spray insecticides in time. I think that if we can do these things well, we will be able to control the phenomenon of insect pests.

The fertility of the soil should be ensured, and the soil should be watered and fertilized in time, and the density should be paid attention to in the planting process, and the spacing should also be paid attention to.

To select high-quality varieties, seeds should be disinfected, physical control, chemical prevention, and cycle management should be carried out before planting.