Why do grapes dry up in spring. Dry grapes, what to do

Growing grapes- an activity that is loved by many gardeners. But this process does not always go smoothly. Sometimes you have to face certain difficulties caused by diseases and various pests. If the grapes begin to dry, and the plant itself loses foliage, then all this becomes a problem that must be dealt with. Sometimes the whole brush begins to dry and most of the crop dies. The moment of drying occurs both when tying berries, and during their ripening. What is causing this drying up? A number of reasons can contribute to this - various diseases caused by fungi and various microorganisms.

The greatest harm is caused by downy mildew, which affects not only the grape brush, but also young and old shoots. Sometimes an entire grape bush dies because of this fungus.

Reasons for the drying of berries

We pay attention to the following:

1. Spotted anthracnose is one of the reasons for the drying of grapes. The greatest number of cases of the development of this disease occurs during the rainy season. Moreover, it must be borne in mind that it can develop not only in the warm season, but even when the temperature is kept around + 2 ° C. This disease affects not only the berries, but also all the green parts of the plant. If anthracnose infects grapes before flowering, then the entire brush will be affected at once.
2. Verticillosis is a disease that affects the plant through the root system, after which the pathogenic microorganism begins to multiply, preventing the plant from receiving the amount of moisture and nutrients it needs. With this disease, grape berries begin to dry. With the progression of the disease on the grape bush, the leaves begin to dry, and then the shoots and clusters gradually suffer.
3. Bending the ridges of the bunches can cause the berries to dry out. Clusters sometimes bend under their own weight, with this position of the brush, the berries do not receive the necessary amount of water and nutrients, which is why they begin to wither and dry. Most often this happens with hybrid grape varieties, because they grow very large bunches. In order to avoid such problems, you should grow a grape bush with the creation of a support. For these purposes, you can use gazebos or arches.

Ways to deal with the drying of grapes

There are no effective ways to combat the drying of berries. Treatment of affected areas or the entire bush with various drugs and fungicides is rather ineffective.

(reklama) It can be recommended to use a three percent magnesium sulfate when the berries dry, or use a half percent sodium chloride solution. It is possible to carry out preventive preparation of the plant by treating it one and a half months before the likely development of drying out, and then carry out several sprayings in a ten-day period.

Treatment with a five percent solution of magnesium sulfate will be more effective at the moment when the grape berries begin to ripen, form under the influence of sunlight, acquire color and cluster. The area should be processed, which will be located next to the ripening bunch of grapes.

But the most reliable, best and most effective way to deal with drying grape ridges and berries will be the correct implementation of all agrotechnical rules. It is necessary to be able to properly trim the vine, to be able to organize a balanced feeding for the grape bush, which includes magnesium and the permitted percentage of nitrogen. In addition to the above, it is necessary to regularly water the grapes, carry out its chemical treatment and apply fertilizers that will prevent the appearance and development of ridge paralysis.

When the vine is healthy and gives a good harvest, the heart rejoices, but it happens when the plants, for no apparent reason, begin to dry, starting with the leaves and ending with the fruits. This is where confusion comes in, because often, especially beginner gardeners, they have never encountered such problems, and they don’t know what to do in these cases, and it’s a pity for the grapes - so much work has been spent on growing it. So why do grape leaves dry? This question remains relevant for many growers.

The vine leaf dries out for many reasons that gardeners need to learn to recognize in order to identify the problem that has befallen their beloved vineyard in time and begin to eliminate it in a timely manner. If time is lost, it may not be possible to heal the plants.

Grapes - leaves dry, what could be the reasons:

• insufficient amount of moisture;
• all kinds of diseases and pests;
• damage to the root system;
• lack of microelements in the soil;
• wrong choice of variety;
• violation of the conditions for growing crops;
• fad.

lack of moisture

Although grape plants prefer hot weather, however, moisture is a necessary condition for normal growth and fruiting. If you do not water the vineyard in a timely manner, then, first, the leaves of the grapes will begin to dry, then the fruits will wither, and the root system will get sick. As a result, the entire plant may die. It is very easy to eliminate this reason - regularly and on time to water the plants in specially prepared grooves for irrigation, and so that the moisture does not stagnate, loosen the ground around the bush more often without touching the roots. If the space around the plants is mulched, then the liquid will not evaporate from the soil surface for a long time.

Fungal diseases and pests

Numerous diseases cause symptoms such as drying out of the leaves of a grape plant. The main disease that causes drying is chlorosis, which has several types.

Verticillosis also contributes to the fact that the leaves of the grapes dry. The disease first affects the roots of the bushes, as a result of which the process of plant nutrition is disrupted. Because of this, minerals cease to flow into the plant itself and the leaves dry up, first along the edges, and then completely, later completely disappear. The scary thing is that this disease manifests itself only in the second or third year after infection.

When grapes become ill with a spotted mosaic, first yellow streaks appear on the leaves, then spots, and in the end the leaves dry and fall off.

Grapes, why do the leaves dry? The cause may be mildew and oidium - the most famous misfortunes of grape culture. It is very sad that not only adult plants, but also grape seedlings suffer from them.

Gray mold on grapes can also cause dry leaves. It spreads in humid and warm weather, affecting first the leaves, then the fruits, and then the whole plant.

A disease such as cercosporosis provokes the drying of leaves, which is dangerous not only for leaves, but also for berries. It appears on the underside of the leaves in the form of an olive coating, after which the leaves begin to dry out and fall off.

Infectious rubella, which occurs during extreme heat, can cause changes in the leaf blade, which first changes color to red, then the structure of the leaves changes - they become thicker, at the same time, their fragility increases due to a lack of potassium.

The main ailment that causes drying is chlorosis.

Alternariosis also manifests itself in hot and dry weather. Grape leaves begin to dry along the edges, as with a lack of potassium, then they become covered with yellow spots and, over time, fall off completely.

Escoria or black spotting is accompanied by drying of leaves and shoots, the appearance of black spots on them, drying out and death of brushes. The disease is very dangerous, as it affects the entire plant as a whole.

Pests

Spider mite raids on a vineyard can cause vine leaves to dry out. This pest is so small that it is very difficult to see it with the naked eye. A sign of damage to a plant by a pest is a cobweb formed at the junction of a leaf with an escape. If the tick is noticed in time, then it will still be possible to prevent the death of the plant.

Root damage

If the grape leaf dries, then a possible reason is damage to the root system, which can occur due to improper loosening of the soil, or unsuccessful shelter of the vine for the winter. Rodents - mice, moles and arthropods can also damage the roots.

Micronutrient deficiency

For grape culture, the content of microelements such as nitrogen, potassium and phosphorus in the soil is very important. Their lack can cause problems, as a result of which the leaves of plants dry out. First of all, it concerns nitrogen. Correcting the situation is very simple - abundant fertilization containing nitrogen. The stores sell a huge number of different nitrogen-based fertilizers. One of the most popular is urea. You can use ammonium sulfate, ammonium nitrate, an aqueous solution of sodium nitrate for top dressing. From organic substances, cow and horse manure, as well as chicken manure, diluted with water, are perfect. Potassium deficiency manifests itself as dry edges of the leaves, which, subsequently, completely dry out and fall off. In addition to nitrogen, it is also necessary to remember about feeding grapes and other trace elements that plants need for good growth. It is important to ensure that there is no oversaturation with minerals, which is also extremely harmful to the grape culture.

Wrong choice of variety

If the climate is cold in the region, and crop varieties are chosen that do not tolerate cold weather, then they are most vulnerable to the incidence of various diseases, as a result of which the leaves can dry out. The right choice of grape variety will minimize the risk of disease and ensure the normal functioning of grape plants.

Violation of growing conditions

Grapes, dried leaves? Such symptoms can be caused by a lack of sunlight and heat, a lack of moisture, and soil that is not suitable for the crop variety. Plants should be planted in such places that they are as comfortable as possible - there is enough light, mineral components. It is worth protecting the vine from frost, covering it for the winter, protecting it from cold winds. It is necessary to timely process grapes from diseases and pests, and prune plants, monitor the condition of the soil under the vine bushes, and water and fertilize in time.

craze

Due to the fact that diseases can be transmitted from one plant to another, mass infection can occur. If it is not possible to cure a diseased vine bush, then it is better to destroy it in order to avoid disease of other plants.

What to do if grape leaves dry

It is necessary to examine the vineyard more often for disease and pest damage. By the appearance of plants, any disease can be detected at an early stage. If the leaves begin to dry, then the disease has already gone too far.

In order for plants to function properly and be healthy, you need to provide them with decent care. In summer, in the heat, abundant and regular watering is necessary. It is necessary to ensure that the water is absorbed exactly under the root, and does not flow away in different directions.

If there are signs of a lack of trace elements in the soil, then appropriate fertilizers containing the minerals necessary for plants should be immediately applied.

Timely treatment with drugs for fungal diseases will help prevent damage to the vineyard by such dangerous diseases as mildew and oidium, and many others. Now there are many available drugs that will reliably protect your vineyard from various misfortunes. If the plant has already fallen ill, and all its green parts have been damaged, then, in order to avoid infection of the remaining grape bushes, it is worth digging it up and burning it, and planting a new variety resistant to diseases and pests in its place. Many insecticides will help you against spider mites.

To avoid chlorosis, it is necessary to monitor the acidity of the soil, and make the necessary fertilizers in a timely manner.

Grapes are a heat-loving plant that loves the sun and warmth. Growing in the middle lane, we put it under stress, due to which the immunity of grapes is weakened and does not always cope with the disease. The task of the grower is to notice and neutralize any ailment in time. Drying and falling leaves are not uncommon. Before taking action, you need to understand the reasons.

There are many reasons why grape leaves can dry out, and they are all different.

lack of moisture

Often, drying begins when the water regime is violated. Despite the fact that grapes love the heat, they cannot survive without water. With a lack of moisture, the berries first wrinkle, then the greens wilt. If you do not water on time, the leaves will quickly dry out and fall off.

With prolonged drought, small roots are oppressed, and nutrients cease to flow to the plant. The grapevine may die.

Lack of nutrients in the soil

The drying of greenery may be due to a lack of trace elements in the soil. If there is not enough boron or magnesium, the green part between the veins first becomes yellow, then turns brown and dries. In this case, the veins on the leaves remain green.

With a lack of nitrogen, the leaves turn yellow and dry, the shoots do not ripen, the bush itself becomes smaller.

With a lack of potassium, a dry border appears along the edge of the sheet.

Diseases

When affected by a spotted mosaic, the veins first turn yellow, then the entire fabric is covered with spots. After that, the leaf dies.

Often, the drying of the leaves, and subsequently the entire bush, is caused by pathogenic microorganisms - fungi. One such disease is verticillium wilt. First, the root system is affected, which ceases to perform its function and absorb useful microelements and water from the soil. Leaves and stems stop getting food. Drying starts from the edge of the sheet, it looks like burnt. The leaves dry up and fall off completely. Symptoms of the disease appear in the second or third year after infection.

A problem with foliage occurs with chlorosis disease. Due to the lack of iron, it does not produce chlorophyll. The fabric first turns yellow, then the sheet dries up and falls off.

With mildew disease, light, almost transparent spots are first covered, then they become brown. In wet weather, a white coating is noticeable on the lower part of the greenery. In dry hot weather it may not be.

Pests

The pest that causes the leaves on the grapes to dry out is the spider mite. It is very small and not always immediately noticeable. The cobweb at the junction of the leaf with the shoot is proof that a malicious pest attacked the grapes. If you regularly inspect, you can find it on the lower part of the foliage, even before it damages a significant part of the plant.

What to do if grape leaves turn yellow

If every day you go around the vineyard, carefully examining all the plants, paying attention to the slightest deviation from the appearance, then almost any disease can be detected at an early stage. The drying of greens indicates that the violation in the development of grapes has gone quite far.

Water the grapes regularly in hot weather. It is necessary to water under the root, make sure that the water is absorbed into the ground, and does not spread around.

If you know the acidity of the soil on the site and follow the feeding schedule, you can avoid the development of chlorosis. We noticed signs of nutritional deficiencies - feed the grapes, add the missing trace element to the soil. This will keep all the greenery from drying out.

With verticillium wilt, partial pruning, foliar feeding and regular watering will help.

Any insecticide helps with spider mites.

How to deal with if the leaves dry around the edges

The edges of grape leaves most often dry up with a lack of potassium in the soil. It is usually enough to simply feed the grapes with potassium sulfate in dissolved form, because the liquid fertilizer is absorbed faster by the root system.

Faced with a disease of the vine, novice growers often cannot determine why the leaves of the grapes dry, what to do to prevent the death of the plant. There are many factors that affect the condition of the grape bush. Methods of dealing with diseases can also be different.

When growing grapes, there are many difficulties due to which you can lose a good harvest.

Grape Features

In order to properly prescribe treatment, you must first determine the cause of the disease, find out why the leaves of the grapes dry and wither. Growing grapes in the northern regions, it is almost impossible to avoid various grape diseases. Bushes sheltered for the winter often suffer from high humidity and poor air circulation, which favorably affects the reproduction of fungal diseases.

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What are the causes of diseases?

The causes of diseases can be hidden not only in climatic conditions. Violation of the composition of the soil, lack of watering, cool or insufficiently sunny weather also affect the health of the plant. At the same time, not only do the vine leaves change color and dry out, but the vine comb dries out, the berries begin to crumble and the bush becomes very weak.

Plants affected by infectious diseases infect neighboring bushes. If no action is taken, the entire vineyard may die. Some of the diseases are quite difficult to treat, so the only way to get rid of them is to replace the plant with one that is immune to a particular type of pathogen.

A hallmark of mildew disease are yellow spots on the surface of the leaf.

One of the most common diseases of grapes is called mildew, its causative agent is considered to be a fungus that affects the leaves, shoots and berries of grapes. A distinctive feature of the disease is yellow spots on the surface of the leaf and traces of a powdery coating of white or grayish color on its lower part. This disease is contagious for neighboring grape bushes, so you need to start fighting it right away, barely noticing the first signs.

Dill sown around the grape bush can serve as a prevention of mildew grapes. The main treatment for already diseased plants is the treatment with Bordeaux mixture in the period between bud break and flowering. In the early stages of the disease, treatment with Ridomil-gold is effective, however, if a month or less is left before harvesting, treatment is not recommended.

The second most common is the fungal disease oidium. It manifests itself, as a rule, during periods of drought, and the first sign of the disease is the appearance of characteristic ash-colored spots on the leaves of the plant. Subsequently, the leaves dry and fall off, and the berries crack and rot.

To avoid the appearance of this fungus, it is necessary that fresh air constantly circulate around the bush and between the shoots of the plant. This requires timely thinning of greenery and weeding. You can eliminate the signs of the disease that have arisen with the help of a solution of colloidal sulfur, they spray the plant from the outside.

Gray rot also refers to fungal diseases. It occurs in a warm and humid environment around the plant and spreads to its upper part without affecting the root system. Spring disease manifests itself in the form of a gray and fluffy coating on the leaves. When the leaves are swayed by the wind, the plaque crumbles, affecting the entire plant. The entire crop is at risk, as the berries of diseased grapes change color to brown and quickly rot.

A solution of baking soda will help get rid of some grape diseases.

Of the simple means to help fight this fungal disease, you can use a solution of baking soda (0.5 tsp per 1 liter of water), which the plant is treated with after removing the affected parts.

All leaves and shoots affected by gray rot must not only be removed from the bush, but also burned to prevent the spread of the disease to surrounding plants.

Drying of grape leaves can also be triggered by cercosporosis. This is another of the fungal diseases, which manifests itself in the appearance of an olive-colored plaque on the underside of the leaves, after which the leaves quickly crumble, and the plaque passes to the clusters, hardening the berries, and adding a lilac tint to their natural color. Berries crumble at any touch.

The infected parts of the plant must be removed and burned, and the remaining bush should be treated several times with a Bordeaux mixture.

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Less common grape diseases

Rubella is the oldest known infectious grape disease. The disease manifests itself in the hottest time of the summer season, and, as the name suggests, manifests itself in the reddening of the leaves of the plant. First, the leaves turn red, then they become thicker, becoming smooth and brittle due to a lack of potassium. Applying a fertilizer containing 1% potassium nitrate will help to cope with the threat of crop loss. As a rule, fertilizer is applied by spraying before sunrise or after sunset, so that the leaves do not suffer further from sunburn.

It will take 3-5 spraying approaches with an interval of about 10 days between them.

Phomopsis disease is manifested by drying of leaves and shoots, and the presence of black spots.

Alternariosis disease manifests itself in hot and humid weather. Symptoms of the disease are similar to oidium, as they appear as light spots on the leaf surface with necrotic foci in the center. At first, a dry border forms on the leaves, similar to the symptoms of potassium deficiency. In the rainy period, the leaf darkens, mold forms on it. The berries are first covered with a veil with a metallic sheen, then with a velvety coating characteristic of mold. In this case, preparations from systemic fungicides are used to treat grapes: Skor, Quadris, Colfugo Super, etc. The period of time between treatments is 10-14 days.

A disease similar in symptoms to black rot, and accompanied by escoriosis, drying of leaves and shoots, and the presence of black spots is called phomopsis. In this case, the disease affects the berries immediately after the flowering period, and they begin to rot in 6-7 weeks. Dried bunches and shoots fall off.
Protect the plant from the disease by timely autumn pruning of shoots and burning of damaged parts. Additionally, spraying with Bordeaux liquid or zuparen is used.

Of the pests, a population of spider mites can cause reddening of the leaves. To get rid of it, the plant is treated with special preparations.

There is no grape variety that is not susceptible to disease. But you can initially select for cultivation those varieties that are less susceptible to diseases and have increased resistance to fungal diseases.

Timely care, removal of diseased shoots and leaves, top dressing and spraying will help save both plants and crops.

We treat diseases

In my opinion, disease is the only deadly threat to the vine. The most delicious and beautiful varieties are most affected by diseases. Despite the efforts of breeders, this law has not yet been overcome. Carriers of genes for resistance to mildew - the most formidable disease - are varieties with a mediocre taste, high acidity, and, like Isabella, a sharp "fox" aftertaste. Unfortunately, when trying to cross tasty and stable grapes, it was not possible to get good offspring for a long time - disease resistance genes are transmitted only along with bad taste. But now there is hope that with the help of genetic engineering it will be possible to obtain varieties of the highest quality. It will soon be possible to assemble the grape genome "brick by brick" from several parents, placing in it genes that protect against diseases and pests, and taste, and aroma, and color, and everything that is good in different varieties and forms.

But for now, it will be necessary to do protective treatments unambiguously. Moreover, according to the scheme and on time, alternating preparations.

Descriptions of diseases are not arranged in alphabetical order, but according to the degree of their prevalence and harmfulness to grapes.

initial stage

mass defeat

Alternariosis

Downy mildew, grape pernosporosis, the most dangerous disease of grapes, is widespread - wherever there are vineyards, there is mildew. The causative agent is a fungus. Lives on living tissues. It affects leaves and green shoots. The fungus overwinters in spores on fallen leaves and soil, easily tolerates frost and heat. In spring, it germinates at a temperature of 10 C. With wind or rain splashes, the spore falls on the reverse side of the leaf.

During the season there can be up to 20 generations of the fungus, only the complete death of the plant or a decrease in temperature will stop the reproduction of the pathogen
up to + 13 C.

Outwardly, the disease manifests itself as the appearance of numerous yellowish spots.

In wet weather, the reverse side of the leaf, due to the active reproduction of the fungus, is covered with a moldy coating. There is no flight in dry weather.

If the variety is resistant to mildew, the symptoms will be more blurred - the spots will be small, dry quickly, and may look like needle punctures with dried edges. The leaf thus acquires an oily sheen.

Spots appear on infected green shoots - oblong, first yellowish, then brown. Later, they, like the leaves, become moldy.

The tops of the shoots on unstable varieties can be especially affected. Then the inflorescences are affected, the clusters of berries that have just started. If the infection occurs later, when the berries are already large, bluish-gray depressed spots form under the stalk. Later, sometimes already colored berries shrivel, turn brown and fall off.

Only a system of preventive, advance treatments will prevent the outbreak of this disease in your vineyard and protect your crop.

- powdery mildew, ashtray - a fungal disease of grapes.
It affects all green parts of grapes at any time during the growing season. Like most fungal diseases of plants, it came to Europe from America in the middle of the 19th century. It is found everywhere where grapes grow. It causes especially great damage where there is an early spring and a moderately warm summer.

The fungus - the causative agent of oidium - lives only on living tissues. Winters in cracks in the bark, kidneys in the form of mycelium - mycelium. In the warmest areas of grape cultivation, oidium appears very early - freshly sprouted shoots can be completely covered with a moldy coating. In other regions, the disease appears later on leaves and clusters in the form of individual spots. Pathogen activation time - temperature +25 C and high humidity. At this time, the plaque appears on both sides of the sheet, it is compacted and becomes bright.

Oidium remains on the plant throughout the season and continuously produces spores that can immediately germinate and form new vine lesions. Closer to autumn, the plaque grows so much that it becomes like felt. The leaves turn yellow, become covered with a dirty gray coating, and bend. Young bunches and flowers dry up. If the infection occurs during the filling of berries, the skin and pulp crack, the seeds turn outward. This is a very characteristic feature for oidium.

Young green shoots may become moldy. With a strong defeat from the bushes, it can smell like rotten fish. Brown spots of irregular shape sometimes appear on the old vine.

Contributes to the outbreak of the disease warm winter, warm damp spring. Unlike mildew, prolonged rains stop the spread of oidium. The disease can completely destroy the crop and weaken and then destroy the vineyard in 2-3 seasons.
You can fight oidium with the help of colloidal sulfur, ground sulfur, Thiovit-Jet, Topaz, Skor, Bayleton.

You can see the terms and frequency of processing or On the page

Fungal disease of grapes. Distributed everywhere.
In recent years, it has been increasing its harmfulness more and more. Hot, humid weather favors the disease. It affects leaves, petioles, shoots, berries. The disease looks like an oidium - the shoots are covered with brown or silver spots. Light spots first appear on the leaves with characteristic necrosis in the center, then the leaf darkens and becomes covered with mold in wet weather. On the berries, the fungus forms a film that gives them a light metallic sheen, then a velvety coating forms. They shrivel, and the taste becomes spoiled and unpleasant. If the clusters were infected in the field, but the development of the disease, for example, due to dry air, did not occur, then the fungus will easily start growing during storage and spoil the already harvested crop.
To distinguish alternariosis from oidium, you can place the affected part of the shoot or leaf on a damp saucer, cover with a damp glass and put in a warm place - after a few hours, if it is alternariosis, the material will be covered with a velvety coating of olive color. Because of this, this disease has another name - olive blotch.

Fungal disease of grapes. Distributed everywhere. It spreads most actively during heavy rains with hail, causing mechanical damage. The pathogen is activated in a humid environment in a wide temperature range from 2 to 30°C. For the season can give up to 30 generations. Young leaves and shoots are affected in spring. Brown dry spots 1–5 mm in diameter appear on the leaves, surrounded by a brown-black border, sometimes with angular edges. The affected areas are often numerous, they can merge with each other or remain single. The center of the spot dries up and becomes gray-white. Dry patches often fall out and give them a "perforated" appearance. Young leaves are most susceptible to infection. Spots can cover the entire leaf, but are more common along the veins. When the necrosis affects the veins, especially on young leaves, the normal development of the leaf is disrupted, resulting in malformed or desiccated leaves. At the same time, the tips of the shoots with young leaves look dried up and as if burned.

Young green shoots are most susceptible to anthracnose. In the spring, symptoms of an early infection may appear from the opening phase of the first leaf on the leaves and shoots of the vine. Depressed brown-brown, violet-brown or violet-black spots form on them. With the further development of the fungus, they acquire an oval shape and a pinkish-gray color, and can also combine with each other. The death of shoot tissues causes longitudinal cracking of the bark, sometimes to the core. Wounds take the form of extensive ulcers. Shoots become brittle and break.

Anthracnose also affects leaf petioles and ridges of brushes. Damage to shoots by anthracnose can be confused with hail damage. The differences between them are that the edges of the wounds caused by anthracnose are raised and have a black color.
The brushes are especially susceptible to anthracnose before flowering and before the berries begin to ripen. The damage on the ridges is the same as on the shoots. Diseased inflorescences dry out completely. If the cluster is pinched by necrosis, then the part of the brush below the necrosis fades.

A sign of damage to berries by anthracnose is spots, sometimes rounded, sometimes angular, depressed, brownish or gray, surrounded by a narrow dark border. The center of the lesion at first has a purple color, gradually becomes velvety. In general, the pattern of spots is similar to the image of a bird's eye, hence one of the names "Bird's eye". Berries may crack.

If the diseased parts of the plant are placed in a moist and warm environment, then an easily flaking pink or pink-orange coating will appear on them.

The pathogen hibernates in affected shoots and in mummified fruits (lasts up to 5 years). At a temperature of 24–30°C and with frequent rains, the incubation period lasts 3–4 days. In dry weather, the spores of the fungus stick together into lumps and do not germinate. In the presence of a sufficient amount of moisture, the mucus swells, and with drops of rain or watering are transferred to other plants.

The first treatments are carried out with copper-based contact preparations at the time the shoots grow by 5-10 cm, further treatments with systemic fungicides Ridomil, Skor, Arcerid, Acrobat) should be carried out with an interval of 10-14 days. After hail falls, it is imperative to treat with fungicides against anthracnose as soon as possible.

bacterial cancer

Bacterial disease of the vine. Found everywhere. The causative agent is a mobile bacterium that penetrates the plant through wounds. Under its influence, normal cells turn into tumor cells. Galls (growths) form on the shoots, which causes vascular obstruction. This leads to a disruption in the growth and development of parts of the shoots located above the tumor. The main source of infection is planting material and infected tools. There are no reliable chemical means of control. It is impossible to eradicate the pathogen from an adult plant. Sick plants, when the first signs appear, are best removed from the site and burned. In place of the affected bush, you can not plant grapes for at least 3 years. In the literature, there are indications that it is possible to improve planting material by placing pharmacy oxytetracycline in a solution. Treatment of diseased bushes at a concentration of 500 units. solution every 2 weeks delays the development of the disease on adult bushes for 2 years. This method has not been proven to be safe. In Australia and the USA, a group of soil microorganisms has been identified that are natural antagonists of causative agents of bacterial cancer.

Apoplexy

Sudden and complete death of the plant. It is caused by certain types of pathogens - verticillosis, fusarium, armillariasis. These pathogens are capable of producing toxins. When pathogens enter the conducting system, plants cause general poisoning. The foliage instantly fades, the plant dies before our eyes. In this case, single bushes suffer. Apoplexy occurs in hot weather in weakened or depleted plants.

Gray rot

A fungal disease that affects many types of plants, is widespread everywhere. It can affect shoots, inflorescences, tendrils, berries and leaves. Harvest after a fungus attack is not suitable for food. In humid weather, the foci can become covered with a dense gray coating, which dusts when touched. In hot and dry weather, the disease proceeds according to the type of noble rot - the berries wither and accumulate a large amount of sugar. You can make wine out of them.

Verticillosis (wilt).

-fungal disease. The disease develops in hot weather 2-3 years after planting, until then the disease develops asymptomatically. The pathogen enters the plant through wounds and root hairs (through the soil). The course of the disease is characterized by rapid withering of the shoots and the death of the plant - apoplexy. In a less acute form, the leaves gradually turn yellow, turn brown and fall off partially or completely. In annual shoots, the nodes lignify unevenly. If you cut across thick roots, stems or withered shoots, then black-brown necrosis is visible on the cut. The pathogen persists for 4 - 5 years in the soil, often infects strawberries - it is not recommended to plant vineyards in areas from under this crop. Other preventive measures include the removal of weeds that may be carriers of the pathogen.
Treatment has not been developed. If the bushes do not die within 5 - 6 years, then they spontaneously recover completely.

Armillariasis

A fungal disease that affects more than 200 plant species. Develops on the roots. The fungus penetrates the root bark, releases extremely toxic toxins. Poisoned wood dies and mycelium settles in it. The penetration of the pathogen causes white peripheral rot. The disease appears in the spring. Leaves wither. The roots become brown, soft, rotten. On the inside of the bark, white films of mycelium are formed. Even one focus of infection can lead to the death of the entire plant. In autumn, with the onset of a wet period, fruiting bodies of the fungus appear on diseased or dead plants - legs 5 - 15 cm tall, caps - 4 - 12 cm in diameter, brown-yellow.
To prevent the spread of the disease, dead plants must be immediately removed and burned, the soil should be shed with a solution of copper sulphate. To prevent the transition of mycelium from natural foci to the vineyard, the vineyard is separated from the forest, forest belts, neglected areas, by a ditch.

Viral diseases

A group of infectious diseases caused by viruses. Little has been studied about the virology of grapes, most diseases have only been described, there are about 35 in total. The pathogen is transferred from a diseased plant to a healthy one only with infected juice - vaccination, sucking insects, nematodes, pruning of a diseased and healthy plant with the same tool, reproduction by parts of an infected plant. The picture of the disease is always different - sometimes the plant can be an asymptomatic carrier of the virus (due to good immunity or varietal resistance), in some specimens the viral infection may have a vague, fuzzy picture, and in some cases the disease proceeds quickly with pronounced lesions.

The first group - NEP viruses - suspected to be spread by nematodes and planting material - cause:

Short knot grapes - the leaves at the same time curly, take an asymmetric shape, the venation becomes abnormal. The internodes are abnormally short, alternating with normal ones, the nodes are sometimes double, the shoots are flattened and forked. Berries fall, bushes degenerate.

yellow mosaic vine - in spring, young leaves and shoots are yellow, then yellow spots or stripes appear on the leaves. Clusters are small with peas of berries. Bushes practically do not grow and degenerate.

vein fringing - in late spring - early summer, chrome-yellow stripes appear along the veins. Growth stops, bushes wither.

Rezuhi mosaic virus (mosaic arabis), Tomato black ring spot virus, Raspberry ring spot virus, Strawberry latent ring spot virus - less harmful viruses, they may not show themselves for a long time, when the plants are weakened - general lethal symptoms appear - a sharp stunting, leaf curl, uncharacteristic coloring of shoots and leaves, and ultimately the death of bushes.
Similar symptoms - variegated color, leaf deformation, growth and development lag, striated wood, discoloration of young shoots giveGrape ring spot virus, Grape chromium mosaic virus, Grape rosette virus other.
From diseased plants, moreTobacco necrosis virus, X-potato virus, Tomato bushy dwarf virus, Alfalfa mosaic virus.

The understudied areAsteroid (star-shaped) mosaic of grapes (random chlorotic leaf spots with central necrosis and leaf deformity),Ainashiki's disease - the disease manifests itself on ripe berries (sugar in berries decreases, ripening is delayed, an unpleasant taste appears),Disease of enations of grapes (parallel outgrowths 0.3-5 cm long and 0.2-0.3 cm wide appear on the lower leaves, the leaves are deformed, the shoots are twisted, later the bush is restored).

More widely distributed in grape wood striation virus - (longitudinal furrows and pits appear on the bark, the bark is thickened and loose, growth is stopped, and the bushes quickly die),grape red leaf virus (the leaves become smaller, turn yellow, and then immediately turn red and fall off),Grape marbling virus, Vein necrosis virus, Grape vein mosaic virus.
Gives a clear pictureVine leafroll virus - in the second half of summer, the leaves turn yellow or redden ahead of time - the strip along the central vein remains green. The leaves themselves thicken, become brittle and twisted, the crop does not ripen.
Control measures: bushes with signs of viral diseases are immediately uprooted. On the vacated place it is impossible to plant grapes for 5 years.

white rot
(white mouth, hail disease)

This fungal disease often occurs on berries damaged by sunburn or hail. The time of its appearance is when the berries reach from half the usual size to the softening stage, which corresponds to the time from mid-June to the end of August. At high temperature (from 18 to 30 C) and high humidity, the disease proceeds very quickly. In a matter of hours, the berries turn brown, acquire a scalded appearance and wrinkle.

root rot

Occurs in soils with excessive moisture. It is caused by a fungus that can exist on dead parts of the plant and, under certain conditions, switch to weakened grape specimens. In affected plants, white threads of the fungus appear between the bark and wood. Often they cover all the roots with a solid white mass. Sick bushes do not grow well, they have short internodes and yellow leaves. After 2-3 years from the onset of the disease, the plant dies completely. The disease can develop as secondary after the defeat of the roots by phylloxera. The tumors caused by the pest are destroyed and diseased tissues become infected with the fungus. The root system dies off in 2-3 years.
Control measures: drainage in damp areas, destruction of diseased plants, if the area is infected with phylloxera, then plant grapes grafted onto phylloxera-resistant rootstocks.

Diplodia

Grape necrosis

Fungal disease - affects ripening berries, shoots and wood. Affected berries acquire a black-bluish color, covered with black tubercles. The disease spreads when hot weather and prolonged rainfall coincide. The pathogen persists on plant debris.
Control measures: after the onset of the disease, carefully remove the affected parts from the bushes, after leaf fall, remove all residues from the site, treat the bushes with 1% Bordeaux mixture. If the vineyard is routinely treated against mildew, then the appearance of the disease is excluded.

This is a group of diseases with similar symptoms - the death of large areas of perennial wood. It may be of an infectious nature or caused by adverse conditions.
Spotted necrosis or dry arm - a disease of a fungal nature - infection occurs during the shelter of the vine with soil in winter. Brown spots appear on the vines, they grow, merge, as a result, the branches die off.
Vessel necrosis of wood - a disease of seedlings, causes darkening of the core and their death in the future.
Bacterial necrosis, Oleiron's disease, bacterial wilt - affects the entire aerial part. On perennial parts, black, deeply depressed spots appear with a brown border. In inflorescences, normal flowers alternate with blackened ones. Shoots in the nodes break and dry out. In spring, the lower buds do not germinate, while the upper buds produce wrinkled, chlorotic shoots. The causative agent is a bacterium. The disease can proceed in an unexpressed form for many years, and flare up in a cold spring. If an infection is suspected, the treatment is carried out before bud break with 5% Bordeaux liquid, after the leaves open 2 more times with 2%. Severely affected bushes must be uprooted.
Non-infectious necrosis can be caused by frost, deficiency of potassium, magnesium, the action of toxic smoke, and so on.

grape burns

Non-infectious damage to plant tissues caused by high temperature (41 C and above) and excessive solar radiation. The leaves turn yellow completely or partially. Damaged areas die off. Berries do not ripen. They acquire a red-brown color, wrinkle. Sugar does not accumulate. In areas where such damage is possible, you need to choose a formation where the clusters are covered with foliage. Sometimes you can untie the vertical growth and lay it along the bunches, that is, close the bunches from the direct sun. Keep the soil moist to help the plant withstand the heat.

Penicillosis

Penicillosis or Blue mold is a fungal disease of grapes. It starts as a small watery light brown spot. As it grows, the spot grows, slightly pressed, then covered with a greenish-gray, or olive bloom. The berry acquires a moldy taste and smell. Appears on berries at the time of ripening. Most often in rainy and warm times, on plants damaged by mildew or pests.

Fusarium

Fungal disease of grapes. The first signs of the disease - yellowing of tissues between the veins of the upper leaves - appear 7-10 days before flowering. A short knot may appear on diseased shoots. The leaves are small, stepchildren appear in large numbers and they are thinned. This form of the disease is called cottis. Growth is markedly reduced. Leaves turn yellow in June. With the onset of hot weather, the green color may return. Berries on infected bushes are substandard - small, uncolored. The bush may die.
Outwardly, the bushes have signs of chlorosis caused by physiological causes. To clarify the diagnosis, it is necessary to make a cross section of thick branches, and preferably a bole - dead vessels will be visible on the cut, and the wood of the base of the bole and perennial wood will be painted pink.
The disease often develops in cold and wet springs.
With systematic treatments of the vineyard with Bordeaux mixture, infection can be prevented. Top dressing with ammonium nitrate can sometimes improve the condition of the bushes.

Bacterial spotting

Bacterioses

E This is a whole group of diseases caused by bacteria. A characteristic feature of these infections is the appearance of specific spots on leaves, ridges, stalks and berries. Bacterioses are widespread and can cause significant damage to the crop.

The disease on the berries begins with a small yellow spot in the depths of the tissue - this is the place where the pathogen penetrates. Then, in this place, a deepening quickly forms, which acquires a brown color. Infection occurs mainly through damaged skin - hail, sucking pests (most often cicadas ), or particles of flying soil or mowed weeds from row spacing during their processing. Some weeds may be involved in the spread and persistence of bacteria, such asfield loach

A characteristic difference between the defeat of bacteriosis and oidium is that during bacteriosis, the affected tissues sink deep into the berry, and when affected by oidium, they are squeezed out along with the seeds.

Within 10 days, the berries dry out and fall off. In the future, they will serve as a source of infection. The development of infection is possible from the beginning of flowering to the beginning of maturation. There is no cure. It is necessary to collect diseased berries and take them out of the site. According to some reports, treatment with Bordeaux mixture or ampicillin antibiotics can reduce the incidence rate. Prevention is possible with Fitolavin.

On stalks and ridges, the disease manifests itself as brown necrotic spots on stalks and ridge ramifications. Diseased brushes quickly wither, flowers and berries fall off. Such infection is possible only during the flowering period. The causes of infection and control measures are the same.