Preparations against black spot on grapes. Grape diseases and measures to combat them. Grape diseases and their treatment

Grape leaves are a catalyst for the condition of the plant; the slightest developmental problems, diseases or pests are immediately reflected in them. appearance. An attentive owner will immediately decipher the signals and understand that the vine needs immediate help. Why do leaves sometimes turn black on grapes?

Blackened leaves indicate grape disease

Possible reasons

There may be several reasons for blackening:

• This happens when mildew has already severely damaged the grapes and, dying, the leaf affected by the disease turns black, but the signs of infection development are completely different.
• With anthracnose, brown angular lesions on the foliage are bordered by a black stripe, and mold develops.
• Grape leaves on cuttings often begin to turn black at the edges from excess moisture or from drying out of the earthen clod.
• Sometimes on young plants the leaves react negatively to the type of soil, dense clay areas do not allow the roots to breathe, and the plant “suffocates.” Here the situation will be saved by the organization of high-quality drainage, the introduction of sand and humus.
• When there is not enough potassium in the soil, the leaves become covered with yellowish spots; when there is a catastrophic lack of the substance, the light blemishes turn black.

Eliminating the deficiency in the latter case is not difficult; it is enough to add fertilizer to the soil, and the green parts will restore their original healthy color, the leaf will again return its bright color.

Why does the leaf on a grape bush turn black, what other reasons cause this phenomenon? If black spots cover the leaves and branches, then black spot develops. The disease is dangerous, it can destroy half the crop in a season, it significantly weakens the plant, it is difficult for it to endure winter, and after a few years, if left untreated, it dies.

Black spots on the vine may be a symptom of black spot.

Pathogen and methods of spread

Black spot is an infection caused by a fungus, another name is Phomopsis or Escoriosis. Microorganisms can be introduced when pruning or when infected seedlings enter the area:

• The fungus infects the green parts of grapes, penetrating into them through lesions or stomata, and is located in the upper part of the epidermis.
• The spores begin to germinate and destroy plant tissue.
• Later, the infection spreads to the wood and parenchyma.

The fungus overwinters in infected buds as soon as the temperature rises above 8 degrees, and is transferred to branches, flowers and leaves with the help of raindrops or insects. A month passes from the moment of infection and visual evidence of infection development. And after just half a month, sporulation organs - pycnidia - form on the black necrotic areas, which continue the spread of the fungus.

Spores develop constantly, so a plant can become infected at any time during the growing season. But more often the infection penetrates the bush in early spring or during the blooming period of flowers. On shrubs, spread also occurs through the growth of fungal mycelium. In rainy, cool spring, black spot development is most active.

The favorable temperature for the development of the black spot pathogen is from 5 to 35°C, but its spores germinate when the temperature rises 1 degree above 0°C.

Escoriosis of grapes begins with small spots on the leaves

Signs of infection

The signs of the disease fully correspond to their name. A typical symptom of the disease is the death of cortex cells and tissues. First of all, the green parts of the plant, branches and leaves suffer:

• Initially, black spot appears in the form of small black or dark brown dots on the nodules of young green branches. If the damaged areas are enlarged many times, swellings of the tissues of the cortex will become noticeable, at the top of which there is a dead mouth, in this place there are necrotic foci.
• After some time, the points grow and connect with each other, become oblong, sometimes they completely ring the shoots.
• Subsequently, as the branches grow, they open in the center, change color, and become light brown.
• Usually on shoots of the first year the lesions spread up to 7 internodes. But when development occurs intensively, the entire branch becomes covered with ulcers and necrosis, cracks, and over time they dry out completely.
• On wood, a sign of fungus is the appearance of gray-white spots in the area of ​​the lower internodes.

On the leaves, manifestations of the disease can be seen already at the beginning of summer:

• First, the leaf becomes covered with dark brownish spots.
• In the center, necrosis becomes black in color with a yellowish border at the edges.
• The spots are located along the veins; due to uneven tension, the leaf becomes lumpy and curled.
• Then, the leaves crack.
• Damaged areas dry out and fall off. When a leaf is severely damaged, it turns yellow and falls off.

Typically, the infection spreads to the lower leaves, and less often to the tendrils and tops of the bunches. They also die and turn black.

Ripe berries infected with fungus:

• first they turn brown, their taste changes;
• become dark purple in color, gradually wrinkle and rot;
• Most often, infection occurs during the flowering period; the process can also affect green fruits; at first it is invisible and appears during ripening.

Many people confuse black spot with the pest, the phyllocoptis mite.

It is not difficult to distinguish the disease if you hold the leaf up to the light. The insect leaves yellowish lesions, and a fungal infection turns them black.

Escoriosis leaves pronounced black spots on the vine and leaves

How to get rid

False spotting can be dealt with only through comprehensive measures: competent agricultural technology and chemical protection. Care measures are aimed at improving vine growth:

• timely garter;
• regular weeding;
• Infected shoots and leaves must be removed and burned;
• To better ventilate the bush, non-fruiting shoots are pruned;
• application of a balanced complex of fertilizers.

Chemical protection requires adherence to a fungicide spraying schedule, otherwise it will be difficult to get rid of black spot. You should know that to destroy the mycelium of the fungus even modern drugs are not effective enough, so the fight must be directed against spreading spores. The treatment must be thorough; the leaves and shoots from below should be sprayed especially well:

• If the disease was noticed earlier, the first spraying is carried out as early as possible, even before the buds open. Bordeaux mixture is used, but the drugs Ridomil and Dron are more suitable.
• The next treatment is carried out when the buds have just swelled or one leaf has appeared on half of the grape bush.
• Another spraying of the grapes is required when 3 or 4 true leaves appear.
• When the berries are formed, processing is carried out almost every ten days until mid-August.
• For preventive purposes, contact fungicides are used: “Ditianon”, “Folpet”.

Black spotting is a disease from which it is not easy to cure a grape bush; sometimes it is chronic; in case of severe infection, measures will have to be taken to eliminate it over several years.

If the owner of the vineyard carefully examines the leaves, he will be able to understand why the leaf has turned black, identify the disease and eliminate problems at an early stage.

Preface

If you want to enjoy tasty and juicy berries every year, you must know grape diseases, their characteristics and methods of treatment. This is what will allow you to get a rich harvest from each bush.

The most famous grape diseases and their treatment

To grow a healthy and strong shrub, you need to prepare for complex work pest control. To do this, you need not only to know about the main causes of plant damage, but also about methods of control and protection. Today we will tell you about the most common diseases of grapes, a competent “war” with which is the key to an excellent harvest and development of bushes.

Diseases and treatment methods may be different, but it is best to remember that preventing grape diseases is much more effective than the treatment process itself. And all due to the fact that there are some bacteria and fungi, which are very difficult to fight - the “infection” spreads too quickly throughout the plant, destroying both the young shoots and the berries themselves.

That is why it is so necessary to understand the importance of preventive protective measures that can protect your entire garden from the adverse effects of various pathogens.

So, the most common ailments:

• Mildew's disease
• oidium,
• bacteriosis, bacterial cancer,
• escoriosis,
• anthracnose,
• various types of rot and spotting of leaves and berries,
• chlorosis,
• wood necrosis,
• leaf rubella,
• septoria,
• Alternaria blight,
• cercospora,
• drying out of shoots.

Examples of some leaf diseases in the photo

Mildew and ways to combat downy mildew

Mildew disease appears during the growing season due to precipitation and affects not only shoots, but also berries. First appears as yellow spots in green areas. With an increased level of humidity, a light coating appears on all inflorescences and diseased leaves. If treatment is not taken in time, the affected areas of the plant dry out or begin to rot.

The powdery mildew fungus overwinters in the soil or foliage, falling on grapes with raindrops or wind. During a season it can produce up to 20 new generations, and the reproduction of the fungus stops either at low temperatures or with the death of the grapes. Prevention of this disease consists of removing weeds, thoroughly ventilating, spraying grape leaves with Bordeaux mixture (1%) before the first flowering, immediately after it and when the berry clusters ripen. It is worth noting that treatment is quite ineffective, and therefore it is better to take all measures in advance to prevent the occurrence of the disease.

Bacterial cancer of grape bushes

Unfortunately, there is no treatment for bacterial cancer, which most often affects grape bushes, and therefore prevention will allow you to reduce the risks of the disease. First of all, you need to pay attention to root system seedlings when planting them - there should be no bumpy tumors indicating the presence of cancer. If you find a diseased plant on your site, it must be removed immediately, and this place cannot be used for planting new plants for several more years.

When carrying out, treat the working area of ​​the instrument each time with a solution of potassium permanganate to kill possible pathogens of the disease. Most often, cancer cells penetrate plants during cultivation, when pruning through wounds on branches, through grafting and seedlings when purchased at a nursery. Gradually the disease spreads to all parts of the plant, and enough for a long time doesn't show up at all. Only at elevated temperatures or humidity can uneven tumors appear on the trunk, on the “shoulders”, on the root system and at the grafting sites. The disease first leads to a decrease in yield, weakened development of the bush and its death.

Oidium and methods of combating the disease

Oidium or “ashtray” is a rather harmful disease. It got its name due to a dark gray coating with a characteristic rotten odor. Inflorescences affected by the fungus dry out and the berries do not grow because their skin hardens and cracks. This disease develops well in dark and unventilated areas of the garden when the temperature rises.

In summer, the fungus constantly spreads, and in winter it is found in damaged buds and vines. The plant should be treated when the first signs appear. You can use tools such as Strobi, Vectra, Quadris, Flint, Topaz or use a 1.5% solution of colloidal sulfur. It is necessary to carry out at least four procedures: before flowering, after it, a month later and in the first ten days of August.

Fighting black spot (escoriosis)

A disease such as black spot, which is caused by affecting the plant fungus. The first signs appear at the beginning of summer. So, round dark dots begin to form on young shoots, which grow and spread throughout the plant, merging into uniform spots. Because of this, the vineyard tissue begins to crack. They often “grow” on the leaves oval shapes necrosis, which is surrounded by a lighter border.

If the fungus has infected the berries, they turn dark purple and bad taste. Whitish spots can also appear on mature vines, and the bark, as bacteria grow into the wood, rots, the “shoulders” of the bush weaken and die over time. Destroy the “infection” even chemicals impossible, but spraying the plant with Euparena, Mikala, and the affected parts of the bush are immediately removed and burned.

Anthracnose or bird's eye

This fungal disease can affect the vine of any grape variety. The disease is caused by the imperfect fungus Gloeosporium ampelophagum Sacc. All organs of grapes located above the ground are affected by anthracnose - leaves, bunches, berries, shoots, vines. The first manifestations of the disease can be seen in early spring on young leaves. They wrinkle, then light gray spots appear on them. which turn brown over time. The leaf tissue in these places is destroyed, holes appear, and then the entire leaf disintegrates. Later, a similar picture can be observed on the vines and fruits.

The fungus does not die in winter. It can persist in shoots for up to five years. It becomes active when the temperature rises. The fungus can get on the grapes due to various types of damage due to rainfall, hail, careless pruning, and even during watering.

To prevent the disease, grapes must be treated with fungicides after hail.

To combat the disease, as soon as it is identified and the height of the shoots has reached 5-10 cm, the grapes are treated with preparations containing copper compounds. Most often it is a Bordeaux mixture. Then, at intervals of up to two weeks, they are treated with fungicides.

Chlorosis

Chlorosis is a disease of grapes in which the production of chlorophyll deteriorates. It can be infectious and develop when viral disease yellow mosaic. In this case, it is necessary to fight the disease that caused chlorosis. A non-infectious type of disease is caused by a lack of chemical elements in the plant’s nutrition. Primarily iron. Often those plants that grow on dense soils impermeable to air with chlorosis often develop chlorosis. alkaline reaction. The disease can also be provoked by excessive application of phosphorus fertilizers or organic fertilizers.

The external manifestations of the disease are light color young foliage, uniform yellowing and falling of the upper leaves, weakening of the bush, decreased shoot growth.

To treat grapes from chlorosis, first of all, weekly spraying with iron sulfate is used ( foliar feeding). But the problem can only be solved by eliminating the main cause of the disease - the airtightness of the soil. To do this, increase its drainage, dig it up to increase ventilation, and use mulching.

Gray rot

A fluffy grayish coating resembling cotton wool appears on infected areas, hence the name of the disease. The disease is caused by the fungus Botrytis cinerea Pers, which overwinters in the ridges and bark of young shoots. Grape bushes with increased crown density and insufficient ventilation during high humidity, as well as dense clusters with high sugar content of berries.

All green parts of the grapes can be affected by the fungus. This can be seen by brown spots with a grayish coating appearing on leaves and shoots that dry out in the sun, by changes in the color of woody areas of the grapes, by purple circles on the skin of the berries, which grow over time and the berry dies.

Prevention of the disease consists of ensuring good ventilation of the bush by thinning it.

For treatment, early spring spraying with drugs is carried out, the action of which is directed against this fungus (Antrakol, Mikal, Folpan). This treatment is carried out 1-3 more times per season, alternating drugs.

Black rot

Vineyards with constantly high humidity are often affected by black rot, caused by the fungus Guignardia bidwellii, which enters the plant due to mechanical damage.

The berries are affected by rot. Brown spots appear on them with a white dot in the middle. Subsequently, the grapes turn black and dry out. During rains, the disease takes on the character of wet rot, and during dry periods the berries shrivel and darken.

Infected leaves become covered with creamy patches of dead tissue edged with a dark green edge. Black streaks appear on the bark of diseased grapes, then ulcers and cracks.

The disease, initially invisible, later develops very quickly, and the plant cannot be saved. Therefore, at the slightest sign of disease, the entire vineyard begins to be treated. In the initial stage of the disease, fungicides can give a good result. In the future, mixtures of drugs are selected, taking into account weather conditions, soil type, and grape varieties.

Sour rot

Sour rot gets its name because of the vinegary smell that spoiled berries acquire. It appears as a result of the processing of sugar into vinegar by microorganisms, and their carriers are fruit flies that lay their eggs in grapes.

The means to combat the disease and its carriers is to treat the vineyard with a mixture of insecticide and fungicide. To ensure that the drugs can be used together, their solutions are prepared and mixed immediately before spraying.

Necrosis of wood vessels

This non-communicable disease associated with impaired physiological processes plants, as a rule, seedlings get sick. The vine cells located next to the woody vessels turn brown and die. The plant turns out to be unable to resist the effects of weather conditions.

Scientists believe that the disease is caused by one of the fungi: Fusarium viticolum or Botrytis cinerea. Infection occurs during storage of seedlings in winter.

The disease can be prevented by storing vines with well-ripened wood. At the same time, they cannot be wrapped for insulation with materials such as polyethylene, which do not allow moisture to pass through. Also, when growing seedlings, strictly follow agricultural practices and feed the grapes with fertilizers containing boron.

Leaf rubella

Often this disease appears in the heat or with a sharp change in air temperature. Rubella can be infectious or non-infectious.

Non-infectious leaf rubella signals that the plant lacks phosphorus or potassium. In the first case, the lower leaves and shoots turn red, in the second – the upper ones.

It is not difficult to fight such a disease. It is necessary to give the plant the fertilizers it needs, remove damaged shoots and leaves, tie up the grapes, remove trimmings and fallen leaves, and weed out the weeds.

Infectious grape rubella is caused by the fungus Pseudopeziza tracheiphila Muller-Thurgau. It spreads quickly, affecting shoots and fruits, taking over new vines. By affecting the plant's vascular system, it deprives its organs nutrients– potassium and phosphorus. Plants may die if the fight against the disease is not started in a timely manner.

You can urgently compensate for the lack of potassium by spraying diseased plants with a one percent solution of potassium nitrate. The treatment is carried out once every eight days, repeated five times. To prevent the disease from recurring next season, in the fall the grapes are fed with potassium sulfate or potassium chloride, and next year's spring pruning is kept as short as possible, unloading the weakened plant.

If there is a lack of phosphorus, superphosphate or similar fertilizers are added to the soil, and after 6 days foliar feeding is carried out.

Autumn and spring feeding of grapes is an excellent disease prevention.

Drying of shoots

In a dry year or, on the contrary, an excessively rainy year, the grapevine's metabolism may be disrupted. Because of this, the shoots begin to dry out.

The disease appears when the berries begin to fill up and up to 12% of sugar has already accumulated in them. Suddenly, dark spots appear on the branches. If the disease is advanced, it cannot be defeated. In case of prolonged drought or prolonged rains, which can provoke the disease, experienced winegrowers recommend preventing the possibility of the disease occurring and treating the plantings with a mixture of magnesium chloride and calcium chloride. The concentration of the solution should be 0.5%. In a similar situation, magnesium sulfate is used, but not to spray the entire vine, but to treat those places where the disease has appeared.

For grape varieties that react negatively to the use of chemicals, disease prevention is the application of balanced complex fertilizers.

Alternaria blight

The causative agent of this grape disease is fungi of the Alternaria species, which are activated in the heat or when high humidity. In the second half of the growing season, silvery spots appear on the leaves and shoots, similar to the manifestations of the oidimum disease. Over time, they turn brown, then the leaves turn black and dry out. On ripe berries, the fungus appears as a metallic sheen, which turns into a dark gray coating. The fruits shrink. Their taste becomes unpleasant. The pathogenic fungus overwinters in the bark of diseased plants and in the soil.

Only effective against disease preventive methods. In spring, they begin to treat the vineyard with fungicides containing copper, such as Ditan M-45, Ridomil Gold MC, SP, VDG, which contain mancozeb. When the berries in the clusters close together, every two weeks they are treated with Quadris, Skor, CE, SK.

Armillaria or root rot

This fungal disease caused by several types of fungi. Gray and dark gray threads appear on the roots. Climbing higher up the plant, the fungus infects the wood, it turns brown and dies. In 2-3 years the plant may die.

The external manifestation of the disease is a lack of fruiting, yellowing and a decrease in the size of the leaves. Typically, the disease appears in plants growing on heavy soils, where water can stagnate and there is generally high humidity. The disease spreads underground, moving from the roots of one vine to the roots of another.

To prevent disease, drain wet areas, try not to plant grapes on soil into which air does not penetrate well, loosen the soil as necessary. In the area where root rot was discovered, grapes should not be planted for at least three years.

When the first signs of the disease are detected, the grapes are sprayed with preparations that contain copper: Copper Oxychloride, Abiga-Pik, Bordeaux mixture, Hom, Ordan and others. To limit the spread of the disease, diseased plants are separated from other plantings by deep ditches, the soil from which is laid out on the infected area, and then the soil is disinfected with formaldehyde.

Bacteriosis

Bacterioses of grapes are a group of diseases caused by single-celled organisms – pathogenic bacteria. They most often occur in plants:

• on exhausted kidneys;
• under adverse weather and natural influences;
• in case of non-compliance with agricultural cultivation techniques;
• in the absence of protection from insect pests.

Bacterial infections can be seasonal or chronic. The types of the disease are:

• bacterial necrosis;
• bacteriosis of berries;
• Pierce's disease;
• bacterial cancer.

For each specific disease, its own methods of disease prevention and treatment have been developed. General recommendation preventing bacteriosis is compliance with sanitary rules:

1. Plants that have died from bacteriosis are uprooted and burned. New vines are not planted in their place.
2. Under no circumstances should planting material be taken from diseased grapes.
3. Seedlings and stems are purchased from trusted nurseries.
4. Before planting the cuttings, they are heat treated for half an hour in hot water 35ºС.
5. When pruning grapes, disinfect the instrument in alcohol or solution copper sulfate before processing each bush.
6. The saw cuts are treated with copper sulfate in the form of a 2% solution and sealed with garden pitch.
7. All agronomic activities should be carried out with special care so as not to damage the plant.
8. During pre-winter preparation, contact of grapes with the soil is avoided.
9. Do not overload the plant so as not to weaken it.
10. Antifungal prophylaxis is constantly carried out.
11. Do not over-moisten the soil and do not overfeed the plants.

Varieties resistant and not resistant to such diseases (photo)

Among grape varieties there are those that are less susceptible to the effects of pathogenic bacteria and less resistant.

The first include Aligote, Bastardo, Codryanka, Delight and others.

Among the most susceptible to bacterial diseases are the varieties White Kishmish, Favorit, Rexavi, Zhemchug Saba, Pervenets Magaracha.

There are no grape varieties that are completely immune to diseases caused by bacteria.

Septoria

Small brown spots on grape leaves indicate septoria disease. When humidity is high, mold appears on the underside of the leaf. When dried leaves fall, they spread fungal spores. Muscat grape varieties are most susceptible to this disease.

To localize the disease, damaged plants and fallen leaves are removed.

Prevention of septoria - spraying the vineyard with a one percent solution of Bordeaux mixture.

Cercospora or green mold

Another fungal disease of grapes, cercospora blight, is caused by Hyphomycetales fungi. It usually affects old or weakened plants. The disease comes in two varieties - spring (May-June) and autumn (July-August) cercospora. Other plants, not just grapes, are also susceptible to the disease.

The disease first affects the leaves of the lower tier, where high humidity and shade promote the development of the pathogen. Severe infestation manifests itself in changes in the leaves and middle tier.

Visually, cercospora blight can be identified by the appearance of a dark olive coating on the underside of the leaves. As the fungus develops, it forms oblong brown spots on the upper surface of the leaf. The leaves do not stick well to the branch and fall off at the slightest touch. An olive velvety coating also appears on diseased berries, the fruits harden, and their color darkens. Then the fruits shrink and fall off easily.

Prevention of cercospora disease consists of strict adherence to the order and timing of all agrotechnical measures.

If a disease is detected, its treatment begins immediately. For this:

• remove and burn all affected leaves;
• treat the vineyard with fungicides every two weeks;
• strictly adhere to the watering regime once a month with water heated to 15-20ºС.

Preventive procedures as a guarantee of healthy vineyards

It will help you with most diseases simple prevention. First of all, this is checking seedlings, timely cutting off remaining vegetation and removing diseased bushes. It is better to know grape diseases in pictures than to fight them later in your garden, since this is a very labor-intensive task and does not always have a positive effect. So, preventive spraying of bushes should be carried out before the beginning of the growing season, that is, before the buds open.

This helps reduce the “infectious background”, which means it leads to improved plant development and increased yield. At the same time, diseases can appear both on “young” and old plants, which means that grapes need to be protected throughout their entire life. In the spring, after removal, the bushes should be treated with a 3% solution of Bordeaux mixture. It is best to make it yourself, since the effect of the purchased mixture is an order of magnitude lower. To do this you need a plastic or enamel dishes pour five liters of warm water in which approximately 300 g of copper sulfate is diluted. We also pour five liters of water into the second container, mixing 300 g of freshly slaked lime in it.

In this case, it is necessary to pour a solution of copper sulfate into the “milk of lime”, otherwise the solution will not be effective for the fight. An ordinary iron nail will be an indicator for determining the quality of Bordeaux mixture. To do this, you need to immerse it in a container with a solution, and then just carefully examine it. So, copper should not settle on the nail. After straining our mixture through a strainer, pour it into a sprayer and water the plants, preferably in calm weather. It is important that when watering the solution completely covers the entire bush, including annual vines and perennial wood.

Means for combating grape diseases and their purpose

First of all, it should be noted that both biological and chemical agents can be used to protect shrubs. The first type includes drugs such as Lepidocid, Trichodermin, Gaupsin, Actofit, who seemed to be quite worthy in their work. They have a huge safety advantage for humans, but there is also a small disadvantage - the need to spray the plants weekly and after rains. This is quite affordable due to quite high cost drugs. In addition, labor costs are not encouraging, especially if you have to work with several hundred grape bushes.

It is much more effective and financially more profitable to use chemicals or pesticides. They are used either for preventive purposes or to control pests, weeds and diseases that harm bushes. It is important to pay attention to the fact that such products must be harmless to the grapes themselves, toxic to bacteria and diseases, and low-toxic to humans. To choose the right remedy, you need to understand how they are classified.

Thus, pesticides are divided according to the object of use (combined into certain groups depending on the bacteria to be fought):

• Fungicides are preparations used to treat plants damaged by fungus;
• Bactericides – directed against dangerous pathogens;
• Insecticides – insect repellents;
• Acaricides – preparations against grape mites;
• Herbicides are substances that help control weeds.

In addition, they are divided into contact, system and a third type - combined.

• Systemic ones are used to combat diseases. The drug you use gets on the surface of the leaf, penetrates inside and, with the help of shoots, spreads to all the “organs” of the bush, including protecting its new growths. These include Topaz, Fundazol, Topsin-M, Quadris, Bayleton and Strobi.
• Contact agents are used when signs of disease appear on the green elements of the plant. If you missed this moment, and the damage has become widespread, try to remove the affected leaves by treating the bush with contact fungicides. The most famous drugs in this category include Rovral, Bordeaux mixture, Omite.
• Combined drugs have the properties of not only systemic but also contact substances. The most famous is considered Ridomil Gold.

List chemicals we can continue ad infinitum. It is important to take a reasonable approach to their acquisition and use. For example, we must not forget that pests get used to the compounds used. That is why they need to be alternated with each other, remembering that the repeated use of drugs from the same group is considered undesirable.

Grape diseases affect the quality of the crop. The causes may be poor care behind the bushes, timely pest prevention, excessive watering.

In order to prevent the spread of diseases and pests in the vineyard, it is necessary to know their main signs in order to quickly identify and combat pathology. Our article will help the winegrower understand this.

Common diseases

Grape diseases are conventionally divided into two types:

1. Infectious. Bushes become infected with harmful microorganisms. The threat to grapes is that fungi, viruses, bacteria are transmitted through air, water, pegs, garden tools. Part or even the entire harvest on the bushes is lost. In addition, the vine does not have time to ripen, so you should not expect good yields from the vineyard next year. This is the best case scenario. If you do not treat infected bushes, you can lose entire bushes.
2. Non-infectious. They may appear as a result of improper pruning, mechanical damage to the vine, or unfavorable environmental conditions.

Scheme of development of infectious diseases.

In order not to provoke the emergence of non-infectious diseases, pruning and all other operations should be carried out very carefully, using sharp pruning shears.

Bacterial cancer

The cause of the disease is a rod-shaped bacterium. White growths of varying sizes and shapes appear on the vine. Then they darken and gradually become hard. These parts dry out, and the disease can lead to the death of the entire bush. Most often it appears in the middle of the plant growing season. During this period, it grows very much and can be up to 20 cm in diameter.

Cause: bacterial cancer - result mechanical damage and further damage to the damaged areas by frost. This disease occurs more often in vineyards in the central regions of the country and less often in the southern regions. Therefore, it is important to know how to do it correctly.

Cutting and pruning should be done with great care. This will reduce the risk of bacterial cancer.

Black rot

The spores of the fungus are black, hence the name of the disease. The microorganism overwinters in the soil, under leaves, and the bark of perennial shoots. Therefore, infection can constantly occur.

The fungal disease affects the entire bush, but, above all, the berries. They are colored blue, blue or purple. The berries become soft, then begin to dry out, then turn black and fall off. Round or slightly angular spots dotted with small black tubercles appear on the leaves. The disease spreads very quickly in damp and cool weather. The entire bunch is affected.

Black rot affects all herbaceous parts of the plant, causing the greatest damage to the fruit.

If such unfavorable period does not last long, then only individual berries are deformed, and the entire bunch ripens normally.

White plaque

Reasons white plaque there may be mildew or oidium on the grape bush. But it is possible that this is another fungal disease - white rot. It differs from black rot in that it affects not individual berries, but the entire bunch. The berries become lethargic and wrinkle. Their color changes. They acquire a reddish-brown, brown color. And then they dry up. Leaves are rarely affected. They dry out, but do not fall off the bush.

If there is a period of prolonged rain, a dirty white coating appears on the infected berries. This is the result of the fruiting of the fungus.

If you do not notice and stop the spread of plaque in time, the fruitful vine may die.

The disease is most often provoked by damage to vineyards by hail.

Blackleg

Severe browning of the roots can be observed in the following cases:

• Blackleg. Refers to fungal diseases. Affects seedlings vegetable crops. Grafted or rooted grape seedlings, if planted in contaminated soil, may suffer from this. The shoot below near the root turns black and softens;
• If roots are damaged by frost Freezing of the top layer of soil causes continuous browning of the roots, which subsequently turn black. These signs appear in the spring;
• Black spot. It can affect all parts of the plant. At the end of the grapes flowering, which is around May or June, small black spots appear on the plant.

“Black leg” appears in conditions of high humidity, on flooded and weakened seedlings, so it is important to observe temperature regime and watering.

Mildew

The basis for protecting grapes from diseases is timely treatment of the plant.

Spraying will be effective only if it is carried out in the evening in calm weather. Fungicides and other drugs are used to treat diseases and kill pests.

Fungicides

Fungicides – used to eliminate fungal diseases. Based on their effect on plants, they are divided into three groups:

• System. They are able to penetrate the stems through the leaf blade and, thanks to sap flow, are spread throughout all the vegetative organs of the bush (Topaz, Skor, Quadris, etc.). They are not washed off by rain, which allows you to do only three treatments per season;
• Contact. Affect directly the lesion (Shavit, Cuprozan);

For control, you can use systemic fungicides intended for different cultures: “Karbil Top”, “RidomilGold”. Or use Bordeaux mixture.

The disadvantage of these drugs is that after each rain it is necessary to carry out treatment. There may be 6–7 of them per season.

• Complex. The most effective, as they combine the properties of contact and systemic drugs (Paracelsus, Polychomus, etc.).

Paracelsus has a contact, systemic effect, which compares favorably with other drugs.

Drugs

Pests and diseases can destroy not only the harvest, but also entire vineyards. Therefore, in addition to fungicides, contact protective drugs are used:

• Bordeaux mixture. The concentration varies. So, for preventive purposes or in case of weak development of the disease, a 1% solution is used, and in case of strong development fungus is already 3%. They begin to spray at an air temperature of 11–12 degrees and regularly repeat this operation after each rain;

“Bordeaux mixture” is a remedy for protecting fruit, vegetable, berry and other plants from diseases

Treatment with Bordeaux mixture 15 days before the start of harvest is unacceptable.

• copper oxychloride (Cupritox. Hom). Effective against mildew, low toxicity. Treatment is carried out at least 6 times during the growing season;
• colloidal sulfur. Used against ticks, oidium. Processed carefully bottom part leaf plate.

Prevention measures

Any grape variety requires. Even resistant to fungal diseases. Because pests and diseases in some years under unfavorable conditions external environment, and this very coldy, hail, drought and others cause enormous damage to grapes. On average, yields are reduced by a quarter. In addition, it worsens marketable condition berries, shoot growth is weakened and they ripen poorly. Sick bushes produce a smaller harvest the next year. And if the damage to diseases and pests was large, then the bush may die. Therefore, they try to prevent the onset and development of the disease. To prevent diseases of fungal etiology, Ridomil Gol, iron and copper sulfate are used.

inkstone

It has two positive features:

1. Low toxic substance for the human body.
2. Has a wide spectrum of action: fights pests, restores the structure of damaged wood, protects vineyards from fungal diseases. Such as mildew, oidium, anthracnose, etc. As a result, the yield of the bush increases. The bunch grows large and the berries are juicy.

Preventative treatments begin in the spring before buds open. The second time you can carry out preventive spraying at the end of the growing season. This is a must do in the fall. Treat not only the bush, but also the soil near the plants with a solution of 500 grams iron sulfate in 15 liters of water.

Treatment of grape bushes with iron sulfate is carried out in the spring, before the buds form.

Processing of grapes must be carried out taking into account certain safety measures, even if the packaging with the drug contains a note that it is of low toxicity to humans.

Disease-resistant varieties

IN Lately Hybrids resistant to certain diseases have appeared. At the same time, it may be highly resistant to mildew, but susceptible to anthracnose. Much still depends on the climatic indicators of the area where the crop is grown, the soil, and the condition of the seedlings. Thus, on the southern coast of Crimea, grapes are not affected by mildew every year, unlike regions located at the same latitude. Therefore, the reduced susceptibility of some varieties to diseases does not mean that preventive treatments are not necessary.

These varieties include:

• ;If the berries have exactly these signs, then it is better not to eat them, as this is a fungal disease. True, such berries do not ripen. That's why they don't reach the consumer's table. But it happens that small black dots are visible on the grapes. At the same time, the bunch is beautiful, and the berries are juicy with a color characteristic of the variety. These grapes can be eaten. It will not cause any harm to the body.

  Video

  Here they teach you to recognize grape diseases at their very beginning and teach you how to fight them.
  

  conclusions

  Some of the crops and bushes can be spoiled by diseases and pests. In this case, the shoots do not ripen, the bush weakens and the harvest next year will be low. If the damage is severe, the plantings may die. Among the most common diseases and pests:

  1. Diseases: Mildew, oidium, anthracnose, cancer. Gray, white, black rot and others. Cancer
  2. Pests: Phylloxera, wireworm, fall armyworm, marbled and hairy beetle, spider mite etc.
  3. To fight Phytoncides are used for diseases. Even resistant varieties require preventative treatments. Especially in adverse weather conditions. This can be done with Ridomil Gold, Bordeaux mixture and iron sulfate. The use of iron sulfate for treating apple trees is described. This scheme Can also be used for grape bushes.

Many people are fans of delicious grape berries, which is why they try to plant this crop near their own homes or in their summer cottages.

However, not always and not everyone manages to achieve good results in viticulture. Indeed, along with the existence of a huge number of grape varieties, there are also a large number of grape diseases, as well as pests that can cause harm to the grape bush.

But still, if you take into account the possibility of diseases affecting grapes or notice their appearance in time, you can effectively fight it.

It is in particular about diseases of vineyards that we will devote you below.

Oidium: how to recognize and fight this disease

What you need to know about oidium?

This disease is often called “powdery mildew” because one of its manifestations is a whitish dust on the leaves of grapes. Refers to fungal diseases, it came to our open spaces from the North American continent. It is very dangerous because affects both the grape bush and the crop. The degree and characteristics of the damage will depend on the grape variety.

External signs of damage to a grape bush by oidium

When a grape bush is affected by this disease, many shoots will be stunted in growth, and the leaves on such shoots will be curly. The gray-white dust is especially noticeable on the leaves. As the crop begins to set, this dust will be noticeable on the entire surface of the affected leaves, inflorescences and clusters. Affected by oidium inflorescences and already set berries die and dry out.

It is important to note that the incubation period during which oidium can infect grapes lasts 1-2 weeks. Warm and humid weather has a positive effect on its reproduction and spread. Even at temperatures above 5ºC, this fungus begins to germinate.

What to do to prevent the bush from being affected by powdery mildew

Even simple agricultural practices help fight oidium well. In particular, powdery mildew is afraid large quantity fresh air, reproduces less when thinning a thickened bush.

Also, preventive spraying is recommended for grapes, which should be carried out three times per season: when shoots grow to grapevine up to a length of 15-20 centimeters, before the start of flowering and during the period when peas appear on the clusters.

Methods of treating grape bushes from oidium

For the treatment and prevention of this disease, it is recommended to use special medications. Among them, the most effective and common are “Strobe”, “Thanos”, “Topaz”, “Horus”. Disease-affected leaves, shoots and It is recommended to remove and burn the bunches. This will help stop the further spread of the disease.

Downy mildew or mildew is the most dangerous disease of vineyards

What is the peculiarity of this disease?

Unfortunately, mildew is not only very dangerous, but also the most common disease that affects vineyards. Just like true powdery mildew, mildew can affect absolutely the entire bush. Of course, the degree of damage by this disease is not always the same.

The grape variety and weather conditions will play a big role: the disease spreads best with heavy rainfall and high air humidity.

How to recognize mildew on your grapes?

Mildew appears as round, oily spots that appear on growing grape leaves. At high humidity with bottom side white powder appears under such a stain on the leaf - a powdery coating. Over time, the areas of the leaf affected by such spots begin to die: the leaf turns yellow, and then the “burn” area acquires a red-brown tint.

Such leaves fall. But the damage is not limited to the leaves, but may spread to the inflorescences, on the crest of which long green spots appear. The affected ridge tissue also dies over time, interfering with the supply necessary substances directly to the berries.

Mildew can also infect the entire bunch, covering it with white powder and causing the berries to dry out. This disease is especially dangerous for the reason that without special spraying and under favorable conditions, mildew fungus can occur in one season. capable of regenerating up to 16 times.

To prevent mildew from affecting your grapes, it is very important to take good care of them and select varieties that have complex resistance.

In order for the grape bush to be strong and strong, it needs to be regularly feed with fertilizers, capable of feeding the soil with potassium and phosphorus. It is also important to constantly mulch the soil near the trunk and remove all shoots from the vine.

But the best prevention against mildew is treating the bush with various fungicides. Preventative treatments carried out at the same time as spraying against powdery mildew.

Treatment of a grape bush affected by mildew

To prevent the disease from spreading and to remove the source of its occurrence, it is recommended to remove and burn the affected areas of the grape bush. Also, for planting grapes, it is better to select places where the bush can receive the maximum amount solar heat and light even in the worst weather conditions.

Effectively fight mildew possible with the following medications:

• "Antrakol"
• Mixture of Bordeaux mixture
• "Kuproskat"
• "Ridomil"
• "Strobe"
• "Copper oxychloride"

How to help grapes resist black spot?

Distinctive features diseases

Another very dangerous fungal disease for grape bushes. When describing it, names such as Phomopsis or simply the death of shoots are often used. Often found precisely in those vineyards that grow in areas With increased level air humidity. Black spotting appears for the most part over all green parts of the bush and along the woody vine.

Features of the manifestation of black spot in the vineyard

Discoloration begins on the indicated parts of the grape bush. Typically, this kind of spots affects only 6-7 internodes, although there are cases of damage to the entire bush up to the trunk. After fading and at temperatures above 10ºC, black dots appear on the affected areas - fungal bodies or pycnidia.

If the disease manages to penetrate deeply into the wood, the affected area rots and can cause the death of the entire area of ​​the grape bush.

Black spotting begins to appear in June. striking annual shoots with peculiar round dots, painted black-brown.

As the shoot grows, these points spread and stretch, causing the vine to crack. Sometimes black spot damage affects the leaves and ridges of the grapes. Affected leaves begin to turn red and turn yellow long before autumn.

Preventive measures to help prevent black spot disease

It is very important to know that vineyards are often affected by this disease through damage to the bush. So, with untimely pruning or careless removal of shoots, the wounded areas become especially vulnerable.

Combined with unfavorable weather conditions, all conditions arise for grapes to become infected with black spot. That's why, pruning should not be considered a mere formality, it is worth treating this process with the necessary responsibility and treating the cut areas.

For the prevention of black spotting, those drugs that are recommended for the treatment and prevention of mildew are well suited.

How to overcome black spot in your vineyard?

Chemical methods of combating the manifestations of this disease have not yet given good results. It is very important to remove the fungus itself; for this purpose, in the autumn, after pruning the vineyard, it is treated with copper preparations.

All damaged areas of the vineyard are completely cut out.

Spraying against black spot is carried out in early spring, when the first 2-3 leaves appear on the bush. Fungicides are best suited for such spraying. After this, it is worth spraying about 3 more times. special drugs bush, combining treatment with spraying against oidium and mildew.

The danger of black spotting is that it the disease is considered chronic for vineyards. Therefore, if it has already appeared on the bush, then you will have to fight it for more than one year. However, if you put in enough effort and carry out regular treatments, you can significantly improve the health of the bush.

How to distinguish manifestations of gray rot on grapes?

If in the future the air around the grape bush stagnates, and there is an excess of moisture in the air, a gray coating may even cover the bunches. At the same time, if you touch the affected bunch, it will become dusty.

Thus, the disease completely ruins the harvest. if the weather is dry, then only a few berries may be affected, which wrinkle over time. If gray rot has affected the inflorescences, in dry weather they will simply die and dry out, acquiring a brownish color.

This disease can cause rotting of berries and grape ridges.

Prevention of gray rot: what measures are important to take?

• IN general outline prevention of gray rot is the same as for oidium or mildew: the same drugs are used for regular implementation The disease often does not manifest itself after necessary spraying.
• In order not to independently cause the appearance of gray rot, it is worth considering that this disease primarily affects the places of cuts and those places that have been weakened. Thus, you need to be attentive to the bush and keep a good eye on such places.
• A grape bush becomes more susceptible to gray rot if it is only fed one-sidedly with nitrogen fertilizers.
• It is also worth knowing that even if spring time gray rot has affected your grapes, then when dry summer weather sets in, it will not spread further.

Treatment of grape bushes for this disease

To prevent the disease from spreading throughout the bush, it is important remove affected parts of grapes. Also, in this case, spraying with special preparations will be mandatory. Even if the drugs do not destroy the disease, it will not develop further this season.

Anthracnose: features of damage to a grape bush and the fight against the disease

Characteristics of the disease anthracnose: why is it dangerous for grapes?

Anthracnose, like almost all fungal diseases, often has a very wide affected area. It appears both on the leaves and shoots of the vineyard, and on the inflorescences, and later on the berries.

The disease occurs throughout the world; warm climates, such as on the Black Sea coast and southern Ukraine, are especially favorable for it.

The most negative feature of this disease is its ability to winter and last up to 5 years. Thus, even without external manifestations, grapes can be affected by anthracnose. It is worth noting that during one growing season, the fungus of this disease can produce about 30 generations of its spores.

This disease is especially dangerous for the parts of the bush that are just budding, if at the same time the weather is generous with precipitation.

Features of the manifestation of anthracnose in grapes

Leaves affected by this disease are distinguished by the presence of brown spots on them with a characteristic dark white border. Because of this nature of its manifestation, this disease is often called “bird's eye.”

The spots can often even merge. Just like with oidium, these spots cause the death of leaf tissue. The shoots are also affected by a pink-gray or brownish-brown heel, which look like depressed pits.

The spots on the shoots are also characterized by a dark border. The affected wood cracks over time and ulcers form on the vine. The shoots can generally break and subsequently dry out completely. Leaf petioles and bunch ridges react in the same way to grape anthracnose.

After being affected by the described disease, the inflorescences turn brown and dry out. The berries are also affected by depressed reddish spots, with an obligatory border of a darker color. The disease can deprive the harvest and greatly harm the bush.

What to use to prevent anthracnose in grapes?

This disease spreads especially strongly in rainy weather. Therefore, after the weather becomes drier, the grape bush must be treated with preparations.

It is best to use fungicides, which need to be sprayed on the bush twice before it blooms, and once after, during the formation of grape berries.

It is best to select grape varieties that genetically have good resistance to anthracnose.

Treatment of grape bushes affected by anthracnose

Treating this disease is quite difficult, although success is possible. The following are used as bush treatment preparations:

• "Antrakol"
• "Acrobat"
• Mixture of Bordeaux mixture
• "Kuprosat"
• "Ridomil"
• "Thanos"
• "Horus"

It is important to note that the treatment is carried out both contact (the very first treatment in the spring; copper preparations are used) and systemically (all subsequent ones).

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28.04.2018

Everyone's favorite fragrant and delicious grapes appears on shelves closer to autumn. In order not to have to wait a long time for a juicy delicacy, gardeners grow grape bushes on their own. To maintain health and increase yield, it is recommended to constantly monitor the bush, because one of the problems is the appearance of black spots on berries, leaves, and stems.

Causes of the disease

Most common cause The appearance of black dots on the grapes is a fungal infection of the bush. Depending on the location, as well as additional symptoms and signs, you can independently determine the extent of the lesion and the pathogen. In order to inspect a grape bush, you need to carefully examine the stem of the plant, its leaves on both sides, as well as the presence of new shoots. If the bush is already bearing fruit, you need to carefully examine the berries for diagnosis.

The appearance of spots on berries

The appearance of an unpleasant symptom in the form of multiple small dots indicates that the plant is suffering from a fungal infection. The most common type of this disease is anthracnose. Initially, small inclusions appear, which, as the berry develops, turn into brown or brown spots. A few additional signs of anthracnose:

It is important to know!

Black spots on leaves

It is generally accepted among summer residents that the most beautiful and delicious grape varieties are prone to fungal infection. One of the common problems is black spotting, which at the initial stage is characterized by the formation of black dots on grape leaves . The first signals arrive already in May and early June, when gardeners expect flowering.

The list of signs of excoriosis will help to determine it with accuracy:

Excoriosis can be treated with chemicals if the disease is diagnosed in time.

Preventive measures and methods of control

If fungal infections are ignored for a long time, the bush begins to gradually die. At first, new shoots do not form, the inflorescences dry out, and the fruits are not set. How formerly a gardener takes measures to combat the pathology, the greater the chance of saving the bush.

To remove black spots on grapes, use the following techniques:

Among the preventive measures, it is worth highlighting improved ventilation of bushes, removal of stepsons and extra shoots, digging up rows, weed control, and tying up vines. Digging up the soil between the rows is a must, because some types of fungi tend to overwinter between the bushes. All vines removed during pruning must be burned - this way re-infection can be prevented. Among the folk remedies against fungi, a lime-sulfur decoction is used to help destroy the infection.