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Powdery mildew on an apple tree and methods for its treatment. Powdery mildew on an apple tree: why did it appear and how to fight it? How to deal with powdery mildew on an apple tree

Experienced agronomists, gardeners and just lovers of digging on a personal plot of land know for sure what powdery mildew is on an apple tree. The most important feature disease lies in the ability to infect with pathogenic microflora not only this fruit tree, but also other species. Faced with a problem, many turn to the "green" first aid kit for folk remedies. I must say that this decision is ambiguous, because there are drugs from the trading shop that can fight powdery mildew no worse than grandma's traditional methods. Detailed recommendations and video below.

Powdery mildew pathogen

Like every disease, this one has its own causes. To understand what powdery mildew is and how to deal with it, you can determine the source of infection.

The microscopic fungus has a certain habitat - these are the upper layers of the soil. There is no such soil where mealy mycelium does not live. At proper care behind the plant, it is in an anaerobic state. Active life cycle starts at certain conditions. More on this later.

Causes of the disease

Often, powdery mildew first affects young ones, gradually moving to more rooted trees. Mycelium envelops foliage, inflorescences, ovaries in early summer and already formed fruits in late. All this is facilitated by improper care, insufficient irrigation, weakness of plantings. This, perhaps, is the basic reason for the onset of the stage of acute infection. Among the accompanying bases of harmfulness are:

Powdery mildew on apple leaves

1. Poor choice of fertilizers.
2. Cultivation of soil for introduced varieties vulnerable to many pests.
3. Increase in seating.
4. High concentration of nitrogen in the soil.
5. A sharp drop in temperature.
6. Relatively long cooling period (7-10 days).

By eliminating the above reasons for the appearance of a pathogen, it is possible to avoid unpleasant consequences, such as damage to plantings, a decrease in yield in the fall.

Attention! Mycelium is able to circulate through air, water, smoothly settling on plants. Even infected human hands garden tools can become carriers of microorganisms.

Signs of powdery mildew

The main symptom in the form of a white coating on the green parts of the apple tree is indicated. You can understand that a tree is infected by other identification "marks" of spores:

• lanceolate deformation of the foliage (twisting of the edges, coarsening of the structure, thickening, loss of turgor, redness, drying, falling off);
• death of the tops of the cuttings;
• intensive growth of lateral buds of the lower tiers of the tree;
• crown thickening.

Attention! If one of the signs is found, one should not wait for the tree to recover on its own, but take drastic measures to eliminate the pathogen.

Folk ways to treat an apple tree

Traditional methods of struggle applied to any disease-causing organism have always been effective: they are time-tested, reliable and affordable.

You can fight powdery mildew with folk remedies

Soda and soap can be used to treat the garden. To prepare the composition, the last ingredient is grated, dissolved in water with soda. Proportions are taken arbitrarily, a small amount. The resulting liquid should be irrigated not only with infected areas, but also with the entire surface of the tree.

Attention! You can skip soap in the recipe, since soda, being a natural antiseptic, can effectively master the task on its own.

Treatment of a plant with copper chlorine oxide is an equally applicable way to control powdery mildew in horticulture.

Preparations

The stores sell already prepared dry formulations. There are a large number of them. They act differently, depending on the volume of spore localization. After evaluating consumer demand, marketers have identified several favorite drugs in the fight against powdery mildew. These are: "Tebuconazole", "", "Kumulus", granular urea, "Impact", "Topaz", "Topsin".

Almost all products are diluted with water before use. To prepare the composition, it is important to follow the recommendations on the package.

Attention! To rid the apple tree of spores, it should first be prepared: cut off dried branches, remove damaged ovaries and leaves. Only after that you can start therapeutic irrigation.

A caring attitude to the garden always bears fruit in the form of a good harvest, so it is important to detect and prevent the disease in time.

Powdery mildew on an apple tree: video

Kira Stoletova

Powdery mildew or white coating on the leaves of an apple tree appears for various reasons and can lead not only to the loss of a large amount of the crop, but also to the death of the tree. Basically, the disease is caused by a fungal infection.

Causes of the disease

The infection is very fast. The spores of the fungus penetrate deep into the tissues, sucking the juice from the green parts.

Mature fungal spores can successfully endure wintering on infected foliage, only when the temperature drops to -27 ° they die.

The peak of infection of trees occurs at the beginning of summer - it is during this period that the fruiting body of the fungus is released.

White plaque on the apple tree appears for the following reasons:

• hot weather with sudden changes in temperature and high humidity (fogs, dew, heat);
• trees overfed with nitrogen can become infected with powdery mildew;
• old specimens that have undergone cardinal anti-aging pruning are often susceptible to this sore;
• growth in a clogged and overgrown garden (where the ideal environment for the development of pathogenic microflora).

Signs of damage to trees

1. At first, the leaves are covered with a whitish bloom resembling flour.
2. Over time, the plaque thickens and acquires a brownish tint. Affected organs stop their growth, begin to curl and crumble.
3. Shoots damaged by powdery mildew first turn white, then turn brown, and die off completely at the advanced stage.
4. The flowers are covered with a whitish coating of thick consistency, which is why they bloom in a chaotic manner, deform and dry out. Fruit ovaries do not have time to develop from such buds.
5. A grayish coating and deep cracks appear on the skin of apples.

Development cycle

Fungal spores can be carried not only by wind, but also by water droplets, as well as by contact of sick apple trees with healthy ones.

Powdery mildew, which appeared on one apple tree, negatively affects the development of the entire garden. Trees intensively begin to shed green foliage, reduce the amount of yield.

This sore has two stages of development:

• marsupial;
• conidial.

A sign of sporulation of conidia is a whitish coating on different parts of the tree. The first stage of the development of the disease occurs in early spring, when vegetative buds begin to swell. Infection occurs through infected ovaries.

Conidia are the source of secondary infection.

The first stage of the disease lasts about a month. After this comes the second (in the last decade of May or in the first decade of June) - the marsupial. During this period, black fruiting bodies appear on the foliage and shoots, which cause the death and drying of the affected organs.

Varieties resistant to powdery mildew

When planting, apple varieties resistant to fungal infection should be used:

• Florina;
• Arbat;
• Gold Rush;
• Bridgham Delicious.

Using these hybrid forms when planting, you can save up to 80% of the crop and grow strong and healthy trees.

Fighting methods

Treatment with chemicals

In the fight against white bloom, fungicides are used:

1. Hom or copper oxychloride. blue color the powder is dissolved in warm water according to instructions. Processing is carried out in calm weather at a temperature not exceeding 30 °.
2. Tebuconazole. Systemic fungicide is able to penetrate deep into plant tissues, neutralize the effect of a fungal infection and create protection for three weeks after treatment. This tool is quite effective in the advanced stage of the lesion. He has two analogues - Flutriafol and Penconazole.
3. Phytosporin. Biological preparation, which includes living cells and fatty spores. Crown treatment with this tool can be carried out in any weather. If rainy weather is expected, then the treatment is carried out a couple of hours before the onset of rain and two hours after it.
4. Colloidal sulfur (cumulus). Granular, inorganic fungicide, which is most effective in cool weather - optimum temperature air for processing is 25-27 °.
5. Urea. Nitrogen-containing top dressing, which is carried out at the beginning of the growing season. 200 g of the substance is dissolved in a bucket of water.
6. Impact. Low toxicity, antifungal fungicide that is used in early spring or late autumn. Creates effective protection against powdery mildew for 30 days.
7. Speed Systemic fungicide used for both therapeutic and prophylactic purposes. The effect of the drug comes two hours after treatment. Spraying can be carried out in any weather. For the entire season, plants must be treated at least four times with an interval of 20 days.
8. Topaz. Systemic fungicide, good for early stage defeat. The number of treatments is four, the interval is three weeks.

Folk remedies

From folk recipes in the fight against powdery mildew on an apple tree, it helps well:

1. Garlic infusion. To prepare it, you need 4 peeled and chopped heads of garlic in a bucket of water. Infuse for 5 hours, spray the crown and soil in the near-stem zone with a working solution.
2. Useful vegetation - pyrethrum, mustard, vetch, green pea, marigolds. They are not only planted on the site, but also used to prepare green infusions. 2 liters of chopped grass is poured with 5 liters of water, insisted for a day, then filtered and sprayed.
3. Mix milk solution (1 l) with water (10 l). Lactic acid bacteria adversely affect the vital activity of the fungus, lead to its death.
4. Ash solution (4 kg of ash is consumed per 10 liters of water). They insist for a day, then the crown and the near-stem zone are sprayed with a working solution twice with an interval of 10 days.
5. Soap solution. In 10 liters of water, dissolve 100 g of crushed laundry soap. To the solution add 2 tbsp. l. baking soda, stir well and process the crown at least three times with a frequency of 10 days.

Prevention

In addition to choosing a quality planting material, resistant to powdery mildew, gardeners spend a number of preventive measures to prevent fungal infections.

If you find a white coating on an apple tree, this means that powdery mildew has attacked the tree. This fungal disease causes damage to the garden due to the wilting of leaves, flower buds and fruits. What is this disease and how to deal with it is described in this article.

Powdery mildew is caused by a fungal disease and attacks the buds, flowers, leaves, shoots and fruits of wild and cultivated apple trees. This interferes with the normal functioning of the leaves, reduces the growth of shoots and deforms the fruit.

Symptoms

The first symptoms of powdery mildew can be seen in the spring when there is a delay of 3 to 4 days in the opening of infected buds. The leaves and flowers of these buds are covered with a white or light gray bloom. The flowers do not develop normally or have a greenish tinge that will not produce fruit.

On leaves, powdery mildew symptoms appear as white spots along the edges or underside of the leaf. Infected leaves are completely covered with a powdery coating of spores. If you do not start fighting this disease in time, then by mid-summer the leaves and shoots may turn brown.

Infection

Powdered mold spores reach the apple tree on windy days and primarily infect trees growing in the shade. Favorable conditions are 70% humidity and temperature fluctuations around 10-15°C.

Passing on the wind, spores cause yellow spots on the top of the sheet, along with curled or folded edges. However, the fungus rarely infects mature foliage and does not grow on moist plant tissue. And direct Sun rays And high temperatures and completely kill fungal tissues.

Disease cycle

The fungus overwinters as mycelium (fungal filaments) inside infected buds. Since these buds open in spring, all parts of them are covered with powdery spores. They are easily carried by the wind, infecting new leaves, fruits and shoots. Kidneys can be infected during the period from their formation to their readiness for wintering.

Variety selection

The use of a less susceptible apple variety is perhaps the most effective tool mold prevention. Cultivars show natural resistance to powdery mildew such as Jonathan, Prima and others.

Planting varieties that have some level of resistance to common diseases such as scab, bacterial burn hearth crops, etc. can reduce the number of fungicide treatments.

Powdery mildew overwinters in the buds and, with the advent of spring, infects all new trees.

In the spring, when the buds begin to grow, the fungus colonizes on the shoots and trunk of the tree. Infected apple tree branches have a silvery-gray appearance, their growth slows down and there is a danger of dying off.

In subsequent weeks, during the progression of the growing season, the infection is transferred to the leaves and flowers. Heavily infected trees become weakened. If treatment is not started on time, then by mid-summer numerous brown foreign bodies will be observed on the trunk.

White coating on leaves and fruits

Fungal spore colonies appear as white, felt-like threads on the leaves of the tree. Secondary infections appear first on the lower surface of the leaf, but can also be found on the upper surface in the form of spots (plaque). Infected leaves curl along the edges or flatten in the longitudinal direction.

As the disease progresses, the affected tissues become covered with a powdery (white) coating, acquiring a silvery-gray appearance. The fruits themselves can be distorted by appearance or form. Powdery mildew reduces both yield and quality of apples.

Disease prevention

To prevent the occurrence of fungal diseases, use surfactants. Sulfur spraying can be done to provide some protection against dew symptoms. The spray should be carefully sprayed on shoots, leaves, buds and flowers and repeated every week.

The right choice of top dressings and fertilizers can have a positive effect on disease resistance. However, it should be remembered that overfeeding with nitrogen fertilizers, on the contrary, can cause a risk of infection.

Powdery mildew control measures

Powdery mildew can be controlled by clearing infected buds by spraying fungicides. However, the fungus has some features that make it difficult to deal with it.

The disease spreads in dry weather at temperatures above 20 °C. Rain is known to inhibit spore development. The time of their germination on the surface of the leaves is negligible, so there is fast recovery the number of spores after any reduction.

Plaque control measures must be carefully planned to be effective. The appearance of new leaves on the branches of the apple tree makes it difficult full protection their fungicides. In addition, the buds are protected in the leaf axils, which also makes them less accessible when sprayed.

The most effective method today is spraying apple trees with special preparations or self-prepared ones. Spraying should be done every 3-4 days.

Folk methods of struggle

Potassium permanganate solution - for spraying, mix 1.5 g of potassium permanganate per 10 liters of water. This treatment is best done after precipitation.

Milk solution - mixes 3 liters of whey and 7 liters of water with the addition of 1 teaspoon blue vitriol.

Onion infusion - before spraying, 200 g of husk onion pour 10 liters of boiling water. After one-, two-day infusion, spraying is carried out.

Special preparations

Topaz is well suited to special preparations for the fight against powdery mildew. Treatment is carried out at intervals of 6-10 days by spraying the entire tree. This fungicide is able to protect all organs of the apple tree (branches, buds, fruits) from fungal diseases.

Also, the treatment of various fungal diseases can be carried out with a drug called Abiga-Peak. He is contact fungicide, that is, it causes a damaging effect upon direct contact with the fungus.

A universal preparation is copper sulphate, which is also a contact fungicide and is widely used in various subsidiary farms.

Fundazol is both preventive and medicinal fungicide. This drug should not be used more than 2 times a year, as it is addictive in fungal diseases.

Conclusion

Powdery mildew is a serious fungal disease that can leave you without a crop, or even without an entire garden. Adhere to preventive measures to prevent this disease so as not to encounter the fungus. However, if you still see a white coating on the leaves - do not hesitate!

The spread of fungal diseases in fruit trees, berry bushes and vegetables in our gardens has become widespread. And one of the most common and harmful is powdery mildew.

Great amount garden plots, in each of which several apple trees grow, insufficient preventive care, and the lack of regular use of manure as a fertilizer, has led to widespread powdery mildew in apple orchards. White coating on the leaves, the fall of the ovaries, the drying of the branches - this is all powdery mildew on the apple tree, which every gardener should know how to deal with.

What is powdery mildew

A fungal disease called apple powdery mildew can be distinguished from other infections by characteristic features:

• leaves, petioles and shoots are covered with a powdery-white coating, which darkens with time;
• inflorescences are also covered with a dense whitish coating, deformed and fall off without forming an ovary;
• grow on fruit brown spots, which often crack, the flesh of the apple becomes corky.

Important! The white coating changes color over time and becomes brown-gray, and then darkens.

On the leaves of the apple tree, the disease is expressed in the most definite way - their color changes from green to a gray-white hue. Leaf damage in this disease is the most severe. After some time, the leaves become lanceolate instead of oval, coarsen, curl and, finally, dry completely.

New shoots on initial stage infections are covered with a white coating, which then darkens and becomes brown-gray. For young shoots of branches, the development of the disease ends with the formation of black spots on the fruiting bodies of the fungus and drying out.

Inflorescences also change color. White color changes to a yellow-green hue, with a pronounced deformation of the stamens and pistils. Inflorescences are bent, flowering is noticeably weakening. The flowers fade prematurely and fly around.

The infection greatly reduces the yield, as it prevents the formation of ovaries. Apples with affected stalks crumble before reaching full ripeness. The disease affects the fruits of the apple tree, ripened fruits are covered with a dark coating, lose their taste and aroma.

High yields, which are usually characteristic of an adult apple tree, are becoming a thing of the past. The fungus simply does not allow the development of either leaves or fruits.

The conditions for the development of powdery mildew, like all fungal diseases, are humid and warm weather.

Important! Open gates for infection - untreated and unsealed wounds, cracks, hollows, saw cuts. The absence of even a small area of ​​bark makes the tree more vulnerable.

Powdery mildew on an apple tree is a source of infection for other plants in the garden. Especially susceptible to this disease are cucumbers, zucchini, pumpkins, black currant, gooseberry. Therefore, when you see a characteristic powdery coating on the leaves, you should immediately begin to destroy the pathogen.

Preventive protective measures

• fungicide treatment;
• removal of severely affected leaves and branches;
• crown thinning;
• autumn digging of the soil and its disinfection;
• sufficient application of potash and phosphate fertilizers;
• reduction or elimination of use nitrogen fertilizers;
• planting varieties of apple trees resistant to powdery mildew.

Important! Without waiting for signs of powdery mildew to appear in the garden, it is worth resorting to preventive treatment apple trees with copper-containing preparations.

You can use both traditional preparations - blue vitriol, Bordeaux mixture, and modern means:

• Horus;
• Topaz;
• Speed;
• Maksim;
• Acrobat.

This treatment will protect against various infections. However, many drugs are not dangerous to humans:

• Speed;
• Maksim.

Despite the widespread use of traditional protective equipment, copper-containing substances are toxic. They should be used when the plants are in a state of complete dormancy: in early spring or late autumn. The first spraying is carried out before bud break, the last - after harvesting and the foliage begins to fall.

The German drug Bayleton provides a 30-day cure for infection. Moreover, it protects not only those places that the sprayer got, but the entire plant, as it penetrates into all the tissues of the apple tree.

Every year, gardeners spray apple trees before flowering and after it with harmless home-made compounds:

• soapy-soda solution (50 g of soda, 40 g liquid soap per 10 l);
• a solution of serum with water in a ratio of 1:10;
• decoction horsetail(100 g of grass per 10 l);
• potassium permanganate solution (3 g per 10 l).

The environment that these products create is detrimental to the fungus, prevents it from maturing and spraying.
Spraying is carried out not only on the crown and trunk of the apple tree, but also on the soil under the tree. Disinfection of the earth in the fall with a 5% solution of copper sulphate is a mandatory procedure.

Infection control

If many fungal diseases can be seen only in the last phase, when the spores have germinated on the tree, then powdery mildew is immediately noticeable. The disease is always easier to cure at an early, not advanced stage.

To prevent the disease, you can use safe folk remedies or biological fungicides, but with strong development diseases can hardly be avoided without the use of potent chemical fungicides. The actions of these substances are compared with the action of antibiotics, they are not harmless, but very effective.

Today, the choice of fungicides is so diverse that it is confusing. To properly use these tools, you need to clearly know the rules for the use of the selected drug. It is also worth finding out its hazard class and waiting period, that is, after how many days after processing it will be safe to eat fruit.

Currently, many types of fungicide are produced to combat the pathogen:

1. Copper vitriol with lime milk.
2. Solution 1% Bordeaux mixture during the growing season.
3. HOM (copper oxychloride) or OxyHOM.
4. Horus.
5. Fast, used even during flowering and not only heals, but also protects plants in initial period infection development.
6. Topaz is not washed off by rain.
7. Isabion. The use of the drug Isabion allows the plant to synthesize the substances necessary for life, its composition includes a complete set of amino acids and peptides. In addition to the treatment of Isabion, it increases the stress resistance of the tree, productivity, fruit quality, it is safe. This is the latest fertilizer for use in the widest possible use.
8. Bacterial preparations such as Integral, Fitospori-M, Planriz. They are made on the basis of any one type of bacteria and are completely harmless to people, do not pollute the environment. They have a 1 day wait.
9. Colloidal sulfur solution (40 ha per 5 l).

Important! Copper, sulfur and iron are trace elements necessary for the life of any plant.

Processing an apple tree from a disease with products containing these elements is used as a treatment and as a foliar top dressing.

The fight against mealy requires more frequent processing of the apple tree than for prevention. It is carried out 2-3 times per season on the days of the greatest activity of fungal spores:

• before flowering;
• after him;
• 10-14 days after the third spraying.

The action of fungicides is limited in time, usually 7–14 days. But the fungus not only develops itself, but also scatters spores. It is necessary to destroy not only the current infection, but also subsequent generations growing out of spores. Therefore, the treatment of fungi and pests that manage to grow several generations in one season is always carried out with repetition.

Repeated sprayings are done 10–20 days after the first treatment. Preference should be given to fungicides that are not washed off by rain.

Back in 2006, a report appeared in a gardening periodical that North Korean scientists had defeated powdery mildew with a drug called Menhwa, or Beautiful flower. It was developed to protect flowers from pests. During testing, it turned out that the tool successfully copes with some fungal diseases.

Menhwa is completely harmless to environment, provides the viability of plants, promotes their growth, insects do not develop immunity to it. Unfortunately, the drug has not yet entered the general market.

Conclusion

How to deal with an infection when powdery mildew appears on an apple tree should be firmly known to every gardener. The cessation of the regular use of manure as a fertilizer, which was an excellent disinfectant for any fungal infestations, as well as the huge number of gardens, led to the massive spread of numerous pests and diseases.

Only mandatory prevention and competent agricultural technology will help keep our gardens in a healthy state and collect a stable high yield.

Powdery mildew on apple trees. Control measures

The causative agent of powdery mildew is a fungus that affects leaves, young shoots, inflorescences, rarely ovaries and fruits. The first signs of the disease appear immediately after bud break. Manifestations of primary infection in the form of a powdery white coating appear on rosettes of young leaves and inflorescences. The leaves are deformed and become lanceolate, leaf blades twist the edges down, rough, lose turgor and dry up.
Affected inflorescences lag behind in development, bloom unfriendly, the stamens and petals on their flowers are deformed, the petals become yellow-green. Then the flowers dry up and fall off without forming an ovary. Sometimes a powdery coating is formed on a young ovary, which subsequently disappears, as a result of which, if they continue to develop, a trace of mycelium remains on the skin of the fruit - a mesh.
Powdery-white plaque on the affected organs is the external mycelium and conidial sporulation of the fungus.
Conidia begin to form in early spring, in still closed diseased buds. The mass development of conidial sporulation acquires during the blooming of the leaves and the flowering of the apple tree.
Spreading the garden, conidia fall on young leaves and cause secondary infection, which appears immediately after flowering and repeats continuously, until the end of the growing season. Incubation period lasts an average of 4-10 days and largely depends on weather conditions and cultivar resistance to disease. Favorable conditions for infection are created at a temperature of +18 ... + 25 ° C and significant saturation of the air with moisture. Hot weather reduces the resistance of plants to powdery mildew, the greenhouse effect from hot humid air contributes to the spread and development of the disease. In the second half of summer, the powdery coating on the affected organs coarsens, and in places of significant accumulation of mycelium, in particular, the affected shoots, the fruiting bodies of the marsupial stage of the fungus - cleistothecia are formed in the form of black balls. However, the marsupial stage does not matter in the preservation and development of the infection, because cleistosthecia die during the winter. The fungus overwinters with mycelium in leaf and fruit buds located on the tops of the affected shoots - the causative agent of the disease penetrated into these shoots in the summer.
Chronic damage to the apple tree by powdery mildew negatively affects the productivity of the orchard. As a result of premature leaf fall, the yield can be reduced by 50-80%. Affected shoots freeze after severe winters, their death can exceed 50%, and buds - 85-92%. The freezing of affected organs also has positive consequences. After severe winters, there is a sharp decline in the manifestations of the primary infection, because when the temperature drops more than 20 ° C, the causative agent of the disease overwinters in the affected kidneys and dies en masse.

Protection of the apple tree from powdery mildew
The protection of apple trees from powdery mildew is based on a complex of agrotechnical, chemical and breeding measures.

Selection of varieties
When laying a garden, one should take into account the resistance of varieties to powdery mildew. Among cultivated apple trees, varieties Aidared, Alva, Askolda, Lodel, Fujii are characterized by a rather high susceptibility to powdery mildew, and Alkmene, Antonovka and Imant show a slight susceptibility to the disease. Mid-season include Vitos, Golden Delicious, Jonagold, Liberty, Papirovka, Priam, Rubinola, Champion, Freedom. The varieties Amulet, Arbat, Bridgham Delicious, Williams Pride, Vnuchka, Gala, Gala Mast, Garant, Gloucester, Gold Rush, Edera, Imrus, Scythian Gold, Florina, Revena, Redfree, Remo, Ligol, Zhemchuzhina Kiev have high resistance to powdery mildew. and Pinova.

Agricultural technology
When growing varieties susceptible to powdery mildew prerequisite is the cutting of the affected shoots both during the winter formed and in the spring, after bud break and at the end of flowering, when the diseased organs become clearly visible. Considering that powdery mildew conidia of an apple tree, without losing viability, are able to overcome distances of up to 1 km, diseased and cut branches must be destroyed.
It is impossible to allow excessive thickening of the crown of trees.
The application of nitrogen fertilizers should be clearly balanced, since their excess reduces the resistance of the apple tree to powdery mildew, but potash and phosphorus fertilizers have a positive effect on the resistance of the crop to the disease.

Chemical treatments
Removing the shoots, although it reduces the infectious stock of the pathogen, does not prevent the development of the disease, therefore, the main protective measure is spraying.
Fungicidal spraying against powdery mildew should be carried out in the phase of bud break (green cone), bud separation (before flowering), immediately after flowering and 3-4 times during the summer with an interval of 12-14 days. In total, at least 5-6 sprays should be performed during the spring-summer period.
In dry, hot weather, especially on disease-susceptible varieties, it is advisable to reduce the interval between spraying immediately after flowering and the next few to 6-8 days - during this period, optimal conditions are created for the development of powdery mildew. On varieties characterized by a high degree of resistance to the disease, spraying against powdery mildew is carried out depending on the degree of damage to the trees. Basically, these events are timed to spring period phenophase of the rosebud and after flowering. Sometimes you can limit yourself to 1-2 spraying. Most drugs exhibit a complex protective effect not only against powdery mildew, but also against other diseases. With a strong manifestation of powdery mildew, targeted spraying against the disease is urgently needed. To do this, use special fungicides effective against powdery mildew based on penconazole, tebuconazole, flutriafol, flutriafol mixed with carbendazim, myclobutanil, myclobutanil mixed with quinoxyfen, sulfur, triforin, triadimefon. The use of sulfur-based preparations during the growing season provides protection for the apple tree not only from powdery mildew of the apple tree, but also from mites.