False Powdery Mildew: Preparations, Control Measures On Cucumbers And Onions

False powdery mildew or peronosporosis is one of the most common diseases that affects various plants. The disease is fungal and is caused by the lower fungus Peronospora. The causative agent of this disease persists in both seed material and plant debris, and its activation is observed when the air humidity increases greatly, for example, during prolonged rains or wet weather.

Patterns of the disease

False powdery mildew: preparations, control measures on cucumbers and onions

False powdery mildew-infested plants produce oily round or angular greenish-yellow spots bounded by veins on the front surface of leaf blades. Later, a faintly distinguishable violet-gray patina appears on the underside surface of the leaves.

Over time, the spots grow larger and join together. As a result, the affected leaves become wrinkled, drooping and withering, and then crumble into fragments that can transfer the pathogens to plants located in the vicinity. Because the diseased shrub's foliage begins to die off actively, the fruit sets and develops more slowly than usual, becomes faded and loses its taste.

If the plant is heavily infected with peronosporosis, it can die very quickly because of this. All cultivated plants are susceptible to this disease: vegetables, fruit bushes and trees, as well as indoor and garden flowers.

During one growing season, the disease is capable of forming up to 20 generations and dispersing as many as a million zoospores. "Various pests, such as aphids, whiteflies, etc., also help peronosporosis spread.

Measures to control false powdery mildew

False powdery mildew: preparations, control measures on cucumbers and onions

To cure a plant affected by false powdery mildew, a sulfur solution (50 to 80 grams per 1 bucket of water) is used. It is used to spray the plant itself, as well as the soil surface around it.

The following fungicide preparations are also used to control peronosporosis: Gamair, Alirin-B, Fitosporin-M, Planriz or Gliokladin. The garden or orchard is sprayed with the solution of these preparations at intervals of 15 days. When about four weeks remain until harvesting, all spraying with fungicidal preparations must be stopped, and if necessary, treatment is continued with less toxic and safer folk remedies.

Please note that it is impossible to get rid of the disease only by treating plants with fungicides. It is also necessary to strictly follow the agronomic rules of various crops, as well as to remember about preventive measures for the disease.

Preventive measures

False powdery mildew: preparations, control measures on cucumbers and onions

To prevent the appearance of plants affected by Peronosporosis on your plot, it is necessary to carry out preventive measures. For example, in autumn time, when all the harvest is done, the plot is cleaned of plant residues and the soil is plowed to a depth of 25 to 30 centimeters.

If you had plants infected by peronosporosis on your plot last season, it is recommended to treat the soil in early spring with a solution of copper sulfate (2-3%) or manganese potassium (1%). After treatment, it is mandatory to recultivate the soil. For soil disinfection, the following biological means can also be used: Gamair, Fitosporin-M or Alirin-B.

In order to prevent false powdery mildew, plants are treated with urea solution (7%), ammonium sulfate (15%) or ammonium nitrate (10%) in the early spring period before buds open. Further, trees are treated with a solution of bordeaux mixture (1%): first time - in the green cone phase, second time - at the end of flowering, and third time - during the formation of ovaries. Even after the plant blossoms, it can be treated with such biopreparations as: Gaupsin, Gamair, Planriz, Integral or Mycosan. The biopreparation Planriz is also used for treatment, unlike other preparations, it can be used even when only one day is left before harvesting.

To reduce the risk of Peronosporosis, crops are not grown in the same area every year.

For example, if cucumbers are grown on a certain plot this season, it will only be possible to grow the same crop again after 3-5 years (at least). Otherwise, pathogens will accumulate in the soil, due to which the bushes will grow weak and painful.

Sowing material must be subjected to pre-sowing preparation, for this it is kept in a solution of manganese potassium (1%) or for 15 minutes poured into a thermos filled with warm (45 to 50 degrees) water. Before planting seedlings in the greenhouse or in the open ground, their root system for 2-3 hours is immersed in Trichodermin solution, which is made necessarily according to the instructions (see the package).

For cultivation, it is recommended to choose those species and varieties of crops that are resistant to fungal diseases.

Plantings should not be too dense, and the crowns of bushes and trees should be systematically thinned, because fungi grow and develop best in crowded conditions. Be sure to follow the agronomic rules of cultivation and ensure that the plants are cared for properly and in a timely manner. Those plants that are severely affected by peronosporosis are dug up and destroyed by fire.

False powdery mildew on vegetables

Cucumber Peronosporosis

False powdery mildew: preparations, control measures on cucumbers and onions

False powdery mildew develops most often in August because this is the time when nighttime temperatures drop, resulting in condensation on their leaves, which is considered a great breeding ground for fungal spores. On cucumbers, peronosporosis can develop because there is too much nitrogen in the soil, or when the plants lack phosphorus or potassium.

Peronosporosis most often develops on cucumber bushes growing in the greenhouse because the conditions are favorable for dew.

The first symptoms of false powdery mildew are detected and bushes growing in the greenhouse are sprayed with a solution of a fungicide such as Gold, Copper Oxychloride, Ridomil or Ephal. Those bushes that grow in the open ground, it is recommended to treat with such means as Quadris, Strobi or Acrobat MC. But remember that cucumbers must be treated in time, if you are late even for 2 days, you can not save the plants. That's why you should pay special attention to preventive measures.

If you do not forget about prevention measures, cucumbers will be reliably protected against both false powdery mildew and most fungal diseases.

Prevention measures:

  1. To grow those varieties that are resistant to peronosporosis, for example: Katyusha, Kumir, Photon, Zodiac, Rodnichok, Debut or Dove.
  2. Seeding material is necessarily subjected to pre-sowing treatment, for this purpose it is immersed for a quarter of an hour in warm (about 50 degrees) water.
  3. Just before planting the soil is necessarily treated, for this purpose use Gamair or Fitosporin-M. Then it is deeply recultivated.

  4. In the greenhouse, it is necessary to carefully monitor the level of humidity in the air. Immediately after detecting leaf plates with spots, they should be cut off together with the petioles.
  5. To make the plants less susceptible to pathogens, they should be fed with phosphorus and potassium. Remember not to have too much nitrogen in the soil.
  6. Spray the bushes along the green leaf with a solution of the biopreparation Planriz, which is made from grass extract.

How to save cucumbers from the disease. False powdery mildew. Peronosporosis.

Peronosporosis of onions

False powdery mildew: preparations, control measures on cucumbers and onions

As soon as the first symptoms of the disease are found on onions, stop feeding them immediately with organic and nitrogen-containing fertilizers. At the same time, the onion should continue to be fed potassium and phosphorus.

Stop watering the bed for a while to help lower the moisture level.

To cure onions affected by Peronosporosis, treat them with a solution of Bordeaux mixture (1%), a suspension of Polycarbacin or Arbamide. To prepare the suspension, combine 30 to 40 grams of Polycarbacin or Urea and a bucket of water. Repeat the treatment after 7-15 days. When there are 20 days to harvest, stop the treatment with the Bordeaux mixture.

Remember that if onions are treated with pesticides, their greens are not used for food.

Peronosporosis killer on onions!

False powdery mildew on sunflowers

False powdery mildew: preparations, control measures on cucumbers and onions

If sunflowers are affected by false powdery mildew, they show stunting, their stems are not thickened and their root system is not developed. Chlorotic spots appear on the front surface of leaf plates, and a whitish stain appears on the underside. Only small portion of infected bushes reaches blossoming phase, and inflorescences on them are small with undeveloped small seeds. Specialists count 6 forms of sunflower peronosporosis.

To cure the affected bushes, they are sprayed with products such as: Ridomil Gold, Amistar Extra, Pictor, Abacus, and others of similar action.

In order to prevent sunflower peronosporosis, it is essential to follow crop rotation and farming practices.

False powdery mildew on sunflowers - control with Faer seed treater

False powdery mildew on bushes

Peronosporosis also affects grapes, but in this case it is called mildew. For European grape varieties, this disease is very dangerous. Mildew was introduced to southern France in 1878 from North America.

If the affected grapes are not treated, the damage to the vineyard can be considerable.

The disease affects the upper parts of the stems, foliage, tendrils, inflorescences, young fruit and crests. To save grapes, it will be necessary to carry out timely preventive treatments of bushes, for this use such means as: Cabrio TOP, Polyram, Acrobat TOP or Delan. Treat bushes before flowering, and then with rain, abundant and frequent dews, and high humidity, spraying is carried out 1 time in 7 days. If the weather is dry, the treatment is carried out 1 time in 15-20 days.

Throughout the season, grapes are sprayed 2-8 times as a preventative measure.

Peronosporosis on garden flowers

False powdery mildew on roses

False powdery mildew: preparations, control measures on cucumbers and onions

Unlike powdery mildew, which first affects the leaf plates of roses very close to the soil surface, peronosporosis first affects the top of the plant. Roses become diseased at a time when their buds are pea-sized. The disease develops very quickly, for example, the bushes were perfectly healthy in the evening and the leaves are already falling off in the morning, and the flowering wave is disrupted. Affected plants develop brown spots on their leaves and then a yellow border appears around them.

The leaves fall off almost immediately after the spots appear. But the disease will not kill the rose. Try to keep the humidity down by turning on the heat every night if the shrubs are growing in a greenhouse. If the bushes in the open air are affected by peronosporosis, it is not possible to lower the air humidity level, in which case the bushes can be sprayed with the following products: Ordan, Thanos, Ridomil, Previcur, Acrobat, Consento or Revus.

False powdery mildew.

How to fight and prolong cucumber yield

False powdery mildew on houseplants

Peronosporosis also affects houseplants. Irregular yellow spots are formed on the front surface of leaves, becoming darker and necrotic with time. On the underside surface of the leaf blades appears grayish, which eventually turns black. Yellowing and dying of the leaves is also observed. The disease develops very actively in heavy and acidic soil mixture, and particularly strongly the plant suffers in cramped conditions and under ventilation on shelves or window sills.

False powdery mildew is treated with the same methods used on houseplants as on garden plants, e.g.:

  1. Pre-sowing seed treatment is mandatory. To do this, immerse them in very warm water for a quarter of an hour (about 50 degrees).
  2. Cut off all diseased leaf plates from the bush.

  3. The flower should be sprayed with a pesticide 5 times with a 7 day break, using a solution of Bordeaux mixture (1%), Cuproxate, Bravo, Oxyhoma, Ordan or Kvdris.

False powdery mildew remedies (preparations)

False powdery mildew: preparations, control measures on cucumbers and onions

Peronosporosis is treated with both folk remedies and chemical preparations, more specifically, fungicides. The following pesticides are most popular with gardeners and vegetable growers:

  1. Acrobat MC. This is a contact and systemic-local action drug that is very toxic to humans.
  2. Alirin-B.

    This biological agent suppresses fungal diseases both in the soil and on plants. Its action is very similar to that of Phytosporin-M.

  3. Bordeaux liquid. A broad-spectrum contact agent, very toxic to humans.
  4. Gamair.

    It is a biological bactericide used to control bacterial and fungal diseases both on crops and in the ground.

  5. Gliocladin. This biological drug actively combats fungal pathogens. It is analogous to Trichodermin.
  6. Oxychom.

    A systemic, broad-spectrum drug, it is highly toxic to humans.

  7. Polycarbacin. It is a systemic drug of therapeutic and prophylactic action. It is used to treat vegetable and fruit crops.
  8. Bravo.

    Contact agent of protective action. Its duration of action is from 1.5 to 2 weeks.

  9. Previkur. The systemic preparation is characterized by wide spectrum of action and is used in control of false powdery mildew and root rot.

  10. Ordan. This contact-systemic drug is moderately hazardous to humans.
  11. Ridomil Gold. Contact-system agent. Very toxic to humans.

  12. Trichodermin. This biological agent is used to protect and treat root diseases. It is used to treat both indoor and ornamental plants.
  13. Phytosporin-M. A contact microbial preparation used to protect crops against various fungal diseases.

  14. Quadris. A systemic drug of protective and curative action. It has one unusual property of prolonging the fruiting of plants by 15-20 days.
  15. Revus TOP. This remedy is used for both treatment and prevention of fungal diseases.

Natural remedies

False powdery mildew: preparations, control measures on cucumbers and onions

After the fruits on the trees and vegetables and berries begin to ripen, stop all spraying of crops with poison chemicals that are dangerous to human health. However, the treatment of crops must be continued, but for this purpose they already use folk remedies that are also capable of fighting false powdery mildew.

There are several very effective folk remedies used by many gardeners and vegetable growers to fight against Peronosporosis:

  1. Mix a liter of skim milk and 9 liters of water. Pour 10 drops of iodine (5%) into the resulting mixture. This solution is used to treat all crops.

  2. Pour a couple of cups of wood ashes into a container and pour them with 2-3 liters of just boiled water. Pour the cooled mixture, filtered through a cloth folded 3-4 times, into 10 liters of water.
  3. A very good fighter against false powdery mildew is a solution of manganese potassium, for its preparation combine a bucket of water with 1-2 g of the substance.
  4. When the disease is in the initial stage of development, you can try to deal with it by infusion made from the husks of onions. Combine 10 liters of water with 0.

    2-0.3 kg of onion husks, put the mixture on the fire and let it boil. Remove it from the stove and leave for 2 days to infuse. The strained decoction is used to treat plants.

  5. The manure develops useful microflora that can destroy pathogens, which is why it is often used to prepare a remedy for false powdery mildew.

    Combine water with cowpea in a ratio of 3:1. The infusion will be ready after 3 or 4 days. Stretched means diluted with so much water, so that the final volume of solution was equal to 7-8 liters. The composition is sprayed on crops in the evening or on a cloudy day.

This is PENOPROSION of cucumber and zucchini.

Why cucumber leaves turn yellow.


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