Powdery mildew on roses: description and control measures

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Powdery mildew is an infectious disease caused by fungi. Its traces can be seen not only on flowers, but also on crops, fruit trees and berry bushes.

Spores of this pathogen are characterized by long viability. They can "sleep" in the soil for several decades.

Activation occurs when favorable conditions for reproduction occur.

There are several types of fungi. Powdery mildew on roses is caused by Sphaeroteca pannosa. Its activators are heat, high humidity, an excessive amount of nitrogen compounds in the soil. Most often, rose bushes, which are dense, become infected. Therefore, a musty odor floating around the plant can be considered an indirect sign of the disease.

How to identify powdery mildew and how dangerous it is

First of all, the stalks, petioles and young shoots that are lower than the rest are infected. A white coating forms on them, in which the mycelium can be recognized. After the spores mature, water droplets appear on it. In the absence of timely treatment, sores spread to the entire plant.

As a result, its appearance becomes unattractive, and the aroma emanating from roses changes for the worse. This can be explained by a lack of nutrients.

Leaves captured by powdery mildew, suffer from necrosis, turn yellow due to lack of photosynthesis. Flowers stop blooming, buds are very small.

The plant at the last stage of this ailment is a bare stem, on the surface of which you can see only felt plaque. Due to its structure and features of the latter, the rose does not develop. The resulting cracks become a haven for rot pathogens. Such a bush is unlikely to winter.

The disease has several names. In addition to the generally accepted, there are such popular designations as "linen", "ashtray" and "torment". Obvious symptoms make diagnosis easier.

Pathogens can be transferred from a diseased plant to a healthy one using insects, wind or pests.

The peak activity of fungi begins in June.

The causes of powdery mildew and the general principles of the fight against it on indoor roses

There are a lot of factors that can provoke a disease in plants grown at home:

  • contact of healthy roses with patients;
  • rains falling too often;
  • a sharp change in temperature;
  • high humidity;
  • excess nitrogen and lack of minerals in the soil and other errors during agricultural activities.

To cure the disease, contact and systemic fungicides will be required. The list of the most effective include Fundazol, Amistar Extra, Topaz, Vitaros, Acrobat MC, Skor, Previkur.

Their action can be supplemented with spray formulations prepared according to folk recipes. Before processing, all damaged shoots, leaves and buds should be removed.

Powdery mildew treatment with folk remedies

The sooner an ailment is noticed, the better. Gentle methods will give a good effect if the fungus does not have time to germinate into the internal tissues. The main stage should be preceded by proper preparation, while the affected peduncles and leaves are removed (they differ in a painful appearance and yellow color).

If the disease has been progressing for a long time, pruning should be cardinal. It is not worth it to feel sorry for the removed parts of the plant.

Colonies of mycelium located in the soil are removed by removing the topsoil (if the rose grows in a pot).

The sprayed solution should cover the entire plant. Experienced gardeners recommend dipping the bushes completely. This is the only way to achieve maximum effect. One treatment is usually not enough, the duration of the course is determined based on the composition of the drug.

It should be noted that alternative methods can stop the disease, but not completely eliminate it. Most often you can’t do without special tools.

Processing should be carried out in dry weather. It is advisable that there is no strong wind and heat. Harvesting the composition for future use is not recommended. You need to do as much as you need at one time.

RecipeApplication
Mix liquid soap (5 g), soda ash (25 g) and hot water (5 l).Roses are sprayed 3 times, at least a week should elapse between sessions.
Dilute liquid soap (1/2 tsp), baking soda (1 tbsp. L.) In water (4 l).Processing is carried out three times, the interval is 7 days.
The solution is made of water and potassium permanganate. For 10 liters of liquid, you need to take 2.5 g of potassium permanganate.The interval between sprayings is 5 days.
A medicine will require 10 liters of water and 1 liter of serum.The course lasts 9 days, spraying is done every 3 days.
The broth is prepared from water and fresh field horsetail (proportion 10: 1, respectively). Then he is insisted 24 hours, then boiled again. It should remain on the stove for several hours. After this, the liquid is separated from the solid fractions. The first is diluted with water. 5 parts of water take one part of the broth.Preventive treatment is carried out in summer and spring.
The medicine is made from copper sulfate (5 g) and hot water (250 ml). This mixture is slowly poured into a container filled with soapy water (5 l of water, 50 g of soap).In accordance with the general rules.
2 tbsp. l mustard powder is diluted in 10 liters of water.Suitable for spraying and watering.
Ash is mixed (1 kg) and warm water (10 l). The solution is insisted for 7 days, not forgetting to stir. Liquid soap is poured into the strained composition.Daily processing is allowed.
Take finely chopped garlic (25 g) and water (1 l). Mix, insist 24 hours, filter.The regularity of spraying depends on the condition of indoor plants.
1 l of whey and 10 drops of iodine are added to water.Only 2 sessions are required, an interval of 7 days.
It will take 10 liters of water and 3 liters of fresh manure. This mixture is insisted for 3 days, the resulting liquid is poured into a separate container. Water is added to it (in a proportion of 1:10, respectively).In accordance with the general rules.

Powdery mildew treatment with fungicides

If alternative methods did not give the desired result, and the condition of the rosary constantly worsens, you will have to use special drugs. In their functions, the stopping of negative processes and the complete elimination of the pathogen. Additional bonuses include restorative action.

Fungicides can be biological and chemical.

The former are considered safer. Many use them as growth stimulants. Unfortunately, they do not differ in high efficiency in relation to a severely neglected ailment. Means from this category are most often used for prevention.

Fungicides of chemical origin can harm both humans and the environment. They should not be abused. The advantages of these drugs include fast and powerful therapeutic effect.

Means, costCookingApplication
Fitosporin-M

60 rub for 200 g

Powder: 2 parts of the settled water are taken 1 part of the drug. The resulting mixture was left alone for 3 hours.
Pasta: the composition of it is done in advance. The proportions are the same, the shelf life is much longer. To ensure fixation, liquid soap (1 tsp) must be added to the solution.
Used for treatment and prevention. The frequency of processing depends on the weather. If the summer is rainy, it should be carried out once a week.
Alirin B

80 rub for 20 tab.

It will take 1 ml of liquid soap, 2 tablets of fungicide, 10 liters of liquid soap. The first ingredient is poured as desired. To accelerate development, the composition can be supplemented with a growth stimulator (Zircon, Epin). If the solution is going to be used for prevention, these dosages are halved.Through the drug, they prevent and treat an ailment.
Fundazole

40 rub for 10 g.

Systemic fungicide can be purchased in powder form. For 10 liters of water, 10 g of the drug.Spray three times.
Tilt KE

300 rub per 100 ml.

0.4 ml of concentrated emulsion are taken per liter of liquid.The therapeutic effect lasts for 2 weeks. Processing is carried out if the air temperature is below +30 ° C.

With prolonged use of the same drug, addiction is developed in pathogenic microorganisms.

Mr. Dachnik recommends: measures to prevent the disease

Powdery mildew is easier to prevent than to cure. To reduce the risk of infection of rose bushes, you must:

  • timely remove the affected parts of the plant;
  • regularly weed the rose garden;
  • when planting, observe crop rotation;
  • carefully select seed;
  • feed garden crops, following the recommendations of specialists and taking into account the initial state of the soil;
  • choose mildew resistant varieties of roses;
  • sanitize tools.

Prevention does not take much time. In order for the rose garden to remain an adornment of the infield throughout the warm season, one must strictly follow the plan of agricultural measures. Otherwise, the appearance of powdery mildew, its false variety and parasites, for example, aphids, cannot be avoided.

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