Can mancozeb control potato late blight?

Potato late blight is a devastating fungal disease that causes the death of potato stems and leaves and the rot of tubers, mainly to the leaves, stems and tubers. After the onset of disease, the area and number of leaf lesions increased rapidly, which caused the early death of the plant and the whole field of potatoes, and caused tuber rot, which seriously affected the yield. The lesions on the leaves are grayish-brown, with irregular edges and a faded green circle around them; The lesions on the tubers are brown, irregular in shape, slightly sunken and not soft, which seriously affects the commercial value of potatoes.

Prevention and control measures: choose disease-resistant varieties, and disinfect and sterilize seed potatoes before sowing (plant ash plus chlorothalonil plus new high-fat film can be used for seed dressing) to reduce the source of pathogens. At the same time, after stripping, a new high-lipid film should be sprayed on the surface in time to improve the emergence rate and form a protective film to prevent the invasion of airborne bacteria.

Strengthen field management, pay attention to ditching and drainage of low-lying water-collecting plots, reduce field humidity, inhibit the development of diseases, and spray Diling in a timely manner before potato flowering, tuber formation and expansion period, so as to effectively control the wild growth of branches and leaves in the upper layer of the surface, accelerate the ultra-rapid expansion of underground tubers, enhance the ability to resist insect pests, and ensure the high quality, efficiency and harvest of potatoes.

Pharmaceutical prevention and control. At the beginning of the disease, 58% methalene-zinc powder (or 70% Antaisheng wettable powder) and 800 times of the new high-lipid film should be sprayed according to the requirements of plant protection.

No, mancozeb is a fungicide, late blight is caused by a virus, and only detoxified seed potatoes can reduce the incidence.

Potato late blight can be treated with systemic ** fungicide, which can be silverfarite, or 25% amicida, or 56% amidocai, or 25% Kairun, or 60% Baitai, or Kai, or anti-fast spray.

Before the onset of late blight, protective fungicides can be used for spray protection, if the disease has been shown before the use, the first time to use both **, eradication and protective agents, in order to reduce the number of bacterial sources.

Potato tubers are diseased, there will be dark brown lesions on the surface of potato tubers, the lesions are round or irregular shapes, slightly concave, the tissues under the lesions show dry rot symptoms, the color is brown, and when the humidity is high, there are also black granular mold layers on the lesions. The occurrence of early blight is not very closely related to climatic conditions, and in all areas where potatoes are grown, it occurs every year without specific and obvious climatic conditions. However, the early blight is initially infected, usually at the same time as the expansion of the potato tuber.

Select early-maturing and disease-tolerant varieties, soak the seeds with a new high-fat film, and remove them to dry them after soaking them. It can keep warm, moisturize, absorb swell, improve the germination rate of seeds, and make the seedlings robust. Repel underground pests and isolate viral infections.

At the beginning of the disease, remove the diseased leaves, fruits and serious diseased branches in time, and then according to the concurrent disease situation of the crop during the period, use 50ml of frost bell + 40ml of golden shell or 50ml of frost bell + mildew 30ml or frost bell 50ml + 30ml of lulantilacearum rick, mix with 15 kg of water, 5-7 days to use 1 time, 2-3 times.

Choose a suitable planting base, such as no potatoes or solanaceae crops have been planted in two years, and the soil is loose and clean. Scientific field management, such as reasonable dense planting; timely watering and top dressing; Keep the field well drained and permeable; Remove the diseased plants and leaves in time and take them out of the field for destruction. Pay attention to improving the ventilation and light transmission environment in the field, clean up the diseased leaves and branches in the field in time, harvest as soon as possible, and clean up the residual branches and leaves in the field in time after harvesting, and carry out centralized incineration to reduce the source of the spread of disease bacteria.

Fungicide (thiophanate-methyl + mesomycin) + red is recommended. Inch. Brassica seed potato dressing treatment can cultivate strong seedlings and prevent a variety of soil-borne diseases.

The selection of early-maturing and disease-resistant varieties, the selection of high terrain, fertile soil planting, increase the amount of phosphorus and potassium fertilizer, through reasonable dense planting, timely removal of field disease residues, can effectively reduce the source of disease in the field, after the onset of the disease can be sprayed with mancozeb, zebzeb, difenoconazole and other agents, the effect is very significant.

In the early stage, it is necessary to give potatoes enough pesticides to help potatoes prevent early blight, and of course, a good cultivation environment is needed to better prevent early blight.

First of all, when planting, choose land with relatively fertile and wide soil. In the process of fertilization, you should choose farmhouse fertilizer, do not use fertilizer bought outside. And also to water more, to prevent the occurrence of pests and diseases, if there is a situation of small insects, then be sure to spray insecticides in time.

It is necessary to strengthen field management, reasonable fertilization, control temperature and humidity, and strengthen ventilation and light transmission management.

The Great Famine of 1845 in Ireland was caused by an outbreak and epidemic of potato late blight, which killed 1 million people and uprooted 1.5 million. For this reason, late blight is known in the industry as potato"Cancer"with"The number one killer"。Potato late blight originated in central Mexico and was transported to Europe by sea around the thirties of the 19th century.

The large-scale outbreak of late blight began in China in 1950 and outbreaks occurred in major producing areas. Since the 80s of the 20th century, there have been frequent outbreaks of potato late blight in the world's major producing areas, and the damage caused by the epidemic has attracted widespread attention all over the world.

Potato late blight is a whole-plant disease with a high risk of resistance. It occurs more often under the conditions of high temperature, high humidity and poor permeability. At the onset of the disease, the leaves of the potato plant will appear with water spots, and there will be white hyphae on the back, and the lesions will spread rapidly when the humidity is high.

In the later stage of the disease, it will cause the leaves to wither and wilt, and the diseased parts will turn black and rot. Eventually, it will affect the rotting of the tubers and stop harvesting altogether. Therefore, late blight is a major killer of potatoes and must be prevented.

The following measures can be taken for its prevention and control: First, select disease-resistant varieties. In order to minimize the economic losses caused by the loss of disease-resistant varieties, high-quality disease-resistant varieties should be selected, and the potato planting structure should be adjusted by using variety diversity.

The second is scientific field management. Strengthen field management and improve the immunity of potato plants, such as loosening the soil in time and reducing field humidity. The third is the use of chemical pesticides.

Once the occurrence of late blight is detected, pesticides should be used in a timely and decisive manner to prevent and control it. Commonly used pesticides for potato late blight include methyl oxazole, dimethylmorpholine, mancozeb, axurin, etc. In addition, large-scale use should be avoided, the same fungicide should be used for a long time, and fungicides with different modes of action should be mixed in turn.

When the climate is humid, the surface is dark brown patches, and the subcutaneous potato flesh is also brown, gradually expanding, and finally decaying, because the source of infection is outside the field, the spores fly into the upper leaves from the outside. Dark purple-brown spots appear on young stems, petioles, and flowers, often forming lesions of 20-30 cm on strong tendons. The lesions break around the stem.

Use methafen manganese zinc mixed with water to reach a certain proportion, evenly sprayed, carbendazim, alumicidal wettable powder, ethphosphine aluminum wettable powder and other medicines.

Late blight should be treated with flumorpholine, pyrimidine ester, alkenyl manganese zinc, methyl sulfate, grass and other medicines, and it should be watered frequently.

It is recommended to use chlorothalonil, grass technology These are the most advanced late blight have a good effect, should be paid attention to, frequent watering and fertilization.

Choose pesticides with relatively low concentrations for spraying, spray once every 7 10 days, spray 2 3 times.

Diseases can be prevented, prevention is more important than cure, and it is hoped that farmers can prevent and prevent the invasion of diseases as early as possible.

Frost Bell 30-50ml + Wofeng 25ml + garlic oil 15ml + silicone mixed with water 30 kg spray regularly.

Remarks: Garlic oil should be halved at the seedling stage, 5-7ml.

Frost Bell is an organic pesticide, sprayed with 200 times liquid at a time, can be used, the effect of the treatment attempt.

After the potatoes are flooded a lot, there are a lot of black spots on the leaves, and there are dead seedlings, what kind of medicine should be used?

Late blight is the most serious disease in potato-growing areas. Due to the rapid onset of the disease, once infected, it is often a devastating disaster. People call this disease the potato plague.

Potato late blight mainly affects leaves, stems and tubers. Dark green spots appear on the tops or edges of infested leaves, and white mold appears in humid conditions. The petiole and stem are infected, and the diseased part is dark brown and easy to break.

Tuber disease, brown skin, sunken, hard, inside the tuber, about 1 cm thick necrosis, often rotting at the same time as other diseases. Potato late blight can be controlled, but prevention should be the main focus. First of all, it is necessary to strengthen field investigation and do a good job in forecasting late blight.

For late blight, it is recommended to spray 250 grams of flumorpholine, 48-90 ml of pyrimidine ester per mu, 133-200 grams of 69% alkenyl manganese zinc per mu, 722 grams of methyl sulfate 60-100 ml per mu with amino acid foliar fertilizer control, with an interval of 7 days, or even 2-3 times.

Potatoes can replenish nutrients, diuresis and reduce swelling. Potatoes are rich in vitamins, calcium, potassium and other trace elements, and are easy to digest and absorb, and rich in nutrients. The potassium contained in potatoes can replace sodium in the body and excrete sodium from the body, which is beneficial for patients with hypertension and nephritis edema**.

Potatoes can nourish the stomach and spleen, and potatoes contain a lot of starch, protein, B vitamins, vitamin C, etc. It can promote the digestive function of the spleen and stomach, contains a large amount of dietary fiber, laxative, helps the body to discharge metabolic toxins in time, prevents constipation, and prevents the occurrence of intestinal diseases.

Potatoes can lower blood sugar, blood lipids, and beautify the skin. Potatoes can provide a large number of proteins with special protective effects, ensure the lubrication of the digestive tract, respiratory tract and joint cavity, prevent fat deposition in the cardiovascular system, maintain the elasticity of blood vessels, and help prevent the occurrence of atherosclerosis. Potatoes are also an alkaline vegetable, which is conducive to the acid-base balance in the body and has a certain beauty and anti-aging effect.

Potatoes are one of the most common foods in our lives. Potatoes can be used as a staple food or cooked as a vegetable.

You can choose propylene zinc, chlorothalonil, and grass technology, which have a good effect on ** late blight, if there is late blight, it should also be paid attention to at this time, and it should be watered and fertilized frequently, so that it can also have better disease resistance.

You can use methalene manganese zinc or enoylmorpholine, and you can also use downy mildew hydrochloride and other drugs + potassium dihydrogen phosphate.

Prophylaxis zinc, chlorothalonil, grammatica, can kill 3,000 and so on, all of these drugs can help solve this disease.

(1) Increase the promotion and application of healthy seed potatoes.

It is best to choose the healthy seed potato planting that is transferred in the current year, and all localities should establish a disease-free seed potato base to ensure that the seed potato does not carry bacteria, and effectively reduce the infection source of the pathogen from the seed source, which is a key step in the comprehensive prevention and control of late blight, and it is also an effective way to increase potato yield.

2) Eliminate the central disease strain and grasp the timing of drug prevention and control.

Once the central disease plant is found, it must be uprooted, buried deep to eliminate, and the drug is widely used to prevent and control late blight, which is currently widely used and has obvious effects. After experimental screening, 58 methyl manganese zinc is a pesticide with good control effect on late blight (the yield is increased compared with the control, and the spraying should be started in early to mid-June when the central disease plant appears. Generally, spray pesticides three times in about 10 to 14 days, and spray especially carefully in the range of 30 50 meters around the central diseased plant, if the rain is frequent, the spraying time interval is shortened, and it is increased by one or two times.

We must pay attention to mass prevention and treatment.

3) Improve cultivation techniques and strengthen field management.

In low-lying water-collecting plots, attention must be paid to ditching and drainage to reduce field humidity and inhibit the development of diseases; Combined with cultivated soil, it prevents pathogens from penetrating into the tuber and reduces the incidence of tubers.

Late blight is an endemic fungal disease that is airflow-transmitted. Late blight may occur when the temperature is above 10 and the air humidity is above 85% for 24 consecutive hours. The more vigorous the growth, the more leafy and closed the field, the more conducive to the occurrence and epidemic of late blight.

Control points: Choose resistant varieties that are suitable for local cultivation. Agricultural measures, adjust the sowing date to avoid the late blight period.

Adjust the row spacing of the plants, and change the small row spacing to a large row spacing. Reduce the spread of pathogens by intercropping with crops such as corn. Thicken the soil layer.

Crop rotation and stubble rotation for more than 3 years can reduce the damage caused by soil diseases. For the prevention and control of pesticides, the pesticides should be used in rotation to prevent the emergence of drug resistance. At present, the commonly used agents in production are:

Yinfali, Jinleidomir, Anker, Amicida, Inhibitory, Antaisheng and other protective agents and ** agents. In order to improve the efficacy of the medicine and enhance the adsorption force of the liquid medicine on the leaves, a synergist can be added to the liquid medicine.