What to do if spinach has downy mildew? How to prevent spinach downy mildew?

Crop rotation. The implementation of 2 to 3 years crop rotation in severely diseased fields can reduce the occurrence of diseases. Strengthen field management.

Reasonable dense planting, appropriate sparse sowing, sufficient basal fertilizer, proper watering, reduce field humidity, and improve plant disease resistance. Clean the countryside. If the diseased plants are found, they should be pulled out in time, and the diseased residues and fallen leaves should be completely removed in time after harvesting, and they should be buried or burned out of the field.

1.Agricultural control, in early autumn, the infected spinach should be removed in time, and it should be taken out of the field and buried deeply. 2.

Pharmaceutical prevention and control. It can be sprayed with 1000 times of 64% Anker manganese-zinc wettable powder, or 600 times of 64% alum wettable water. 3.

Fertilizer and water management. Spinach likes to be fertile, moist and cold, avoid drought and stagnant water, and is a fast-growing vegetable. Therefore, it is necessary to supply sufficient fertilizer and water in time during the growth period.

It can be sprayed with 58% Radomir 500 times solution or 75% chlorothalonil 600 times solution, or 50% formabib and Dyszeb zinc, or sprayed with 600 times Pulik aqueous solution. Urea can be used when growing spinach, which can prevent downy mildew.

Spinach downy mildew is a pest and disease that occurs on broccoli caused by downy mildew infestation. Key damage leaves. Leaf disease usually occurs gradually from the lower leaves that stick to the road surface, and slowly develops upwards.

Broccoli downy mildew is produced all over the country. The key disease onset and maturity period of downy mildew of broccoli in Shanghai and the middle and lower reaches of the Yangtze River in China is from March to May and September to December, with a relatively mild occurrence in spring and a heavy occurrence in autumn from September to December.

The prevention of spinach downy mildew is dominated by agricultural and animal husbandry prevention and chemical control. The first to use disease-resistant varieties or to carry out pesticide seed dressing, you can use 75% mancozeb wettable powder seed dressing, the dose is the amount of seeds. Promote seed rotation, pay attention to onion and garlic rotation, prevent heavy cropping, and implement 2-3 year rotation in seriously ill fields.

Reasonable dense planting, immediately replenish seedlings, and improve natural ventilation and light transmittance. Scientific research on watering, draining pipes immediately after rain to avoid flooding. Clean up the pastoral scenery, find that the diseased plants are pulled out immediately, and immediately eliminate the residual and diseased leaves after acquisition, and bury or damage them outside the field.

Finally, organic chemicals are integrated to carry out prevention.

The use of disease-resistant varieties or the development of pesticide seed dressing, can be used 75% mancozeb wettable powder dressingThe dose is the seed amount. Promote rotation, pay attention to onion and garlic rotation, to prevent heavy stubble, and implement 2-3 years of rotation in seriously ill fields. Reasonable dense planting, immediately replenish seedlings, and improve natural ventilation and light transmittance.

Scientific research on watering, draining pipes immediately after rain to avoid flooding. Apply sufficient organic fertilizer, moderate fertilization, pay attention to the coordinated application of nitrogen, phosphorus and potassium fertilizer, and improve the disease resistance of the main stem. Clean up the pastoral scenery, find that the diseased plants are pulled out immediately, and immediately eliminate the residual and diseased leaves after acquisition, and bury or damage them outside the field.

Sprayer prevention should be carried out as soon as possible before or before the onset of the disease, so as to achieve the actual effect of disease control and production. Chemical fertilizers should be applied in a different way to prevent chemical resistance. To prevent downy mildew in broccoli, you can use a liquid sprayer with 600-800 times of 75% mancozeb wettable powder.

In the early stage of the disease, you can use 58% methalenemanganese zinc wettable powder 500 times, or 50% Anker wettable powder 1500 times, or downy mildew carb liquid 600-800 times, or 64% disinfectant alum wettable powder 500 times, spray up and down 1 time every 7-10 days, and spray 2-3 times in a row.

It is necessary to strengthen experience management, apply enough rotted organic fertilizer, pull out harmful plants in time, regularly use drugs for pest control, and timely drainage and irrigation.

First of all, before planting spinach, we must plough the soil, so that we can remove some pests and diseases in the soil, and you can also sprinkle some lime in the soil before planting, which can also play a role in sterilization.

You can choose to spray some pesticides on his roots, which can inhibit the growth of mold, and should also let the sun shine more, which can also kill a lot of bacteria, so it is not easy to get sick.

Spinach downy mildew is a relatively common disease, so it should be planted reasonably when planting. Scientific management, and timely dehumidification and dehumidification. It is important to keep an eye on this disease as it can affect yield and quality.

At the seedling stage, it is necessary to pay attention to reasonable irrigation and top dressing, the ratio of nitrogen, phosphorus and potassium should be reasonably matched, and timely spraying of strong stems to improve disease resistance, promote leaf hypertrophy, fresh and tender leaf color, and strong natural taste.

In the early stage of the disease, 90% ethylphosphine aluminum 800 times + potassium permanganate 1000 times + new high lipid film 500 times were sprayed alternately for 3 times to improve the control effect and reduce the use of pesticides, and change high toxicity pesticides to low toxicity and low toxicity to slightly toxicity.

1. Seriously ill fields should be rotated for 2-3 years.

2. Apply enough well-rotted organic fertilizer to improve the disease resistance of plants.

3. Strengthen cultivation management, achieve appropriate density, scientific irrigation, and prevent flood irrigation to prevent diseases from spreading with the flow of water.

It is necessary to pay attention to heat preservation and ventilation, timely weeding, and find that the diseased plants should be timely, with drugs, and can be sprayed with 25% methyl frost wettable powder to prepare 700 times of water for prevention and control, and spray once every 7 days.

Spinach is susceptible to downy mildew when it is waterlogged in the field, the planting density is too large, and the growth is weak. In the early stage of infection, only light green and faint spots were born on the spinach leaves, which seemed to be dehydrated, and there was really no change if you didn't identify it carefully. This disease is more common in spinach planting areas, the incidence can reach 10% to 25%, and the incidence rate can reach 65% when the disease is severe, which seriously affects the yield and quality of spinach and directly affects the economic benefits of vegetable farmers.

The introduction and improvement of new varieties of spinach, although the yield is high, but the pathogens come randomly, spinach leaf spot, downy mildew. This has had a big impact on the appearance and value of spinach.

<> to overcome this problem, it needs to be governed from three aspects; Spray with methalene, manganese, morpholine, and silver farix. It is advisable to spray early, and spray from the bottom to the top with a nozzle when the blade does not completely cover the ground, spraying the back of the blade. Downy mildew infects from the dorsal of leaves.

If the early stage is well controlled, the incidence will be low and the loss will be minimized. Spraying with mildecarb and other agents, spraying with a drug according to the concentration of use when it is light, and choosing the above two compounds plus iron and zinc fertilizer when it is serious. It is advisable to spray early, and the prevention is greater than **, and it is used when the leaves do not completely cover the ground.

The sprinkler sprays from the bottom up, on the back of the blade. Downy mildew starts with high leaf humidity, that is, the relative humidity is higher than 80%, and the night temperature in the shed is lower than 8-10, and the weather with a large temperature difference between day and night will aggravate the disease. Under the recent rainy and foggy weather conditions in the suburbs of Shanghai, the management of greenhouse ventilation and light transmission is slightly improper, and spinach downy mildew mainly harms the leaves of plants, and can occur at the seedling stage and adult stage.

In the early stage of the disease, there are water-stained green spots, after expanding, they will be limited by the leaf veins to present polygonal or irregular yellow-brown lesions, and the back of the lesions becomes yellow and white causing serious losses.

Crop rotation should be implemented during planting, and reasonable dense planting, scientific water and fertilizer management, and timely drainage and humidity reduction. After the onset of the disease, Anker manganese-zinc wettable powder or alum wettable water agent was sprayed once every 6 to 8 days, and the drug was used continuously for 3 to 4 times.

Reasonable crop rotation, timely crop residue and leaf loss, bring out of the field to bury and burn; and spray the ground with a new high-fat film 800 times to treat the soil; Before sowing, the new high-fat film should be used to dress the seeds, and the seeds should be sown in a timely manner, and then the new high-fat film should be sprayed to keep the surface insulation and moisture to improve the seedling emergence rate.

Spinach downy mildew, we should take 1, strengthen field management, in planting, to be dense and appropriate, strengthen the decay of organic fertilizer, improve plant disease resistance, 2, pesticide control, in the early stage of the disease, early spray prevention and control, to achieve disease control and production.

Spinach downy mildew is a fungal disease. Downy mildew overwinters with hyphae on overwintering spinach and seeds, or oospores in diseased residues, and is the main source of infection through airflow, rain, insects and tillage. Recurrent infections in temperature, rain, and humidity of 7-16 degrees.

Downy mildew is caused by lack of vigor, high planting density, moisture or early sowing, and in severe cases, it can lead to non-harvesting. Spinach downy mildew mainly damages spinach leaves. At the beginning of the disease, the leaves produce pale green spots, which develop into pale yellow spots, and then expand into irregular spots with a white mold layer on the dorsal spots of the leaves.

The lesions spread upwards from the lower part of the plant and are prone to illness at night when there is dew. The diseased leaves turn yellow in drought, rot when wet, turn yellow and die in severe cases, and spinach downy mildew is serious in low temperature and high humidity environment.

Downy mildew prefers low temperature and high humidity environment, spinach is more susceptible to downy mildew infection from the five-leaf stage to the harvest stage, the bacterial incubation period can reach 5 15 days, and it will cause disease in the temperature environment of 3 30. The incidence is higher when the relative humidity of the air reaches 85% at 7 15. At the peak of the disease, continuous rainy weather, or rainfall of more than 50mm, will definitely cause the disease. Downy mildew fungus safely lurks in the field in winter or summer, mycelium parasitizes on spinach residues, and mycelium can also safely parasitize seeds in winter or summer; In the spring of the following year, the hyphae reproduce conidia under suitable environmental conditions, and the conidia are disseminated by air currents, rainwater, insects, farming, etc.

The pathogen spreads to the spinach plant, and then the stomata or epidermis of its host leaf invades first, causing the spinach to be infected with the disease for the first time. At the right temperature and humidity, it only takes 2 to 3 days for the germs to invade the disease.

After the occurrence of spinach disease, downy mildew sporangia will breed, and the sporangia will be spread through air currents, rainwater, insects, tillage, etc., resulting in spinach being infected with downy mildew many times. The rapid multiplication of downy mildew at its peak can lead to multiple infections of spinach. The damage of downy mildew to spinach plants is mainly manifested in the leaves.

Spinach leaves are infected with downy mildew. The pathogen first invades the leaves close to the ground, and the pathogen spreads from top to bottom. In the early stages of the disease, yellowish spots can be seen on the leaves.

As the pathogen spreads, irregular spots appear, and the spots have no noticeable edges. The infected site on the back of the infested leaf will develop a layer of downy mildew, which is also the sporangia of downy mildew. The pre-mold layer is grayish-purple or grayish-white.

When the lesions develop to the middle and late stages, the mold layer will turn yellowish-brown-orange. When the climate is dry, the affected leaves turn yellow, and when the air is humid, the affected leaves rot and turn brown. In severe cases, the lesions will break into pieces and turn yellow or brown, and most of the leaves of the affected plants will turn yellow and die.

The seeds are sown with bacteria, and after germination, they become infected with germs, the seedlings shrivel, and the leaves become smaller and brittle. When the air is humid, the mold layer also multiplies on the leaves, which are also the sporangia of downy mildew, which are spread by air currents, rainwater, insects, farming, etc. When the disease is severe, the seedlings wilt and die.

Select disease-resistant varieties, adjust the temperature and humidity in the shed in time, strengthen field management, the planting density should not be too large, scientific watering, reduce the humidity in the shed, increase phosphorus and potassium fertilizer, and improve plant disease resistance.

Seed Treatment: 58% of the usable seed weight (Methyl Frost?) Manganese-zinc) wettable powder or seed weight of 50 Fumei double wettable powder dressing. Pesticide prevention and control: timely spraying prevention and treatment in the early stage of the disease.

It can be prevented with drugs. Some pesticides can prevent downy mildew in spinach.

In such a situation, it should be watered and fertilized in time, and pesticides should be sprayed in time, and it is also necessary to prescribe the right medicine, and it should also maintain ventilation and light to keep the soil fertile.

In the early stage of the disease, timely spraying can be used to prevent and control 58 Lusujing wettable powder 800-1000 times, or 75 chlorothalonil wettable powder 600-800 times, or 64 frost manganese zinc wettable powder 800-1000 times, or 72 downy mildew wettable powder 800-1000 times, or 72 frosturea? Manganese-zinc wettable powder 700-800 times liquid, or 69 enoylmorpholine manganese-zinc wettable powder 1000-1500 times liquid, or 70 ethylphosphine aluminum? 500-600 times of manganese-zinc wettable powder, or 500-600 times of 50 times of copper wettable powder, or 600-800 times of 80 spreedacen zinc wettable powder, spray once every 7 days, and continuously control 2-3 times.

Pesticides should be applied alternately to prevent pathogens from developing resistance.

Spinach is a common green leafy vegetable that people love to eat, its leaf color is thick green, tender and juicy, rich in life, protein and a variety of trace elements, and is known as "nutritional model student" among many vegetables. However, in the process of spinach planting and management, diseases will be caused in the temperature environment of 3 30 due to weather conditions or improper management; At 7 15 temperatures, when the relative humidity of the air reaches 85%, the incidence rate is higher; At the peak of the disease, the disease must be caused by continuous rainy weather, or when the rainfall exceeds 50 mm.

If it is found that the diseased plants infected by downy mildew fungus are uprooted in time, they should be taken out of the field to burn or buried deeply, and at the same time, quicklime should be sprinkled to treat the planting holes to prevent the spread of the source of disease. At harvest time, the leaves of the residual plants are completely removed and taken out of the field to be buried or burned. Before the onset of the disease, 30% or 45% chlorothalonil tobacco can be used, 200 250 grams per mu can be used, and the shed is smoked in the evening; At the beginning of the disease, 15% chlorothalonil smoke agent can be used, 250 grams per mu, smoked once every other week, and smoked 3 or 4 times in a row.

The front of the leaf initially forms a light green dot, and then expands to a light yellow, irregularly shaped large spot with an inconspicuous edge, and the gray-white mold layer is formed on the back of the leaf and then becomes gray-purple mold, and the diseased spot is yellowish in drought, and the mold layer on the back is less, and the diseased leaf is easy to rot when wet. In severe cases, the diseased leaves atrophy, and as the disease progresses, the lesions will expand, and often several lesions will appear together to show a significant bulge. When the weather is humid, the leaf back disease grows a white moldy mold layer, and when it is severe, the leaf lesions are patched together, dry up and die.

It is caused by fungi, mainly harms the leaves, the damaged part is a light green water-stained round spot at the beginning, the edge is not obvious, and gradually develops into a large yellow round lesion, the diseased leaf is yellow when drought, and a large number of purple-gray mold layers are still born on the back of the diseased leaf when wet, and rot when it is serious. Through the spread of air currents, rainwater, agricultural activities and insect information, there are many signs of re-infection in the field. The disease is more severe when the planting technology density is high, the field is covered or partial nitrogen fertilizer is applied, the plant tissue is young and tender, the growth demand is strong, the humidity changes too much, and the low temperature is more serious.