Grapes are often exposed to a variety of diseases, they are attacked by pests. Because of this, crop losses are up to thirty percent, and in some cases up to fifty percent. In order to avoid loss of crops and vines, it is necessary to carry out the prevention of grape diseases in a timely manner. But if suddenly the plant was struck by some kind of ailment, the treatment should be carried out correctly.
Types of diseases
All grape diseases are divided into infectious and non-infectious. The most contagious - infectious - are represented by such ailments as:
- mildew;
- grey rot;
- oidium;
- anthracnose;
- white rot and some others.
Also, all diseases are divided according to the type of pathogen that causes the disease. It can be viruses, bacteria, fungi. The latter include pathologies such as black spot, mildew and others.
Mildew
Pathogen: Plasmopara viticola Berl. etToni.
Among grape diseases, the most common is mildew, or downy mildew. This is a dangerous disease that affects shoots, leaves, fruits. With a strong defeat, the grapes do not produce the next year.
The disease was brought in the nineteenth century from America to France, and from there it spread throughout Europe and beyond. The degree of harm caused and the level of disease in different territories manifest themselves in different ways. It depends on the climate, planting density. Frequent rains, dews, the subtropical zone can lead to the development of a severe fungal infection of plants.
You can learn about the disease of grapes by signs. Mildew is characterized by the manifestation of the first signs even at the stage of unfolding the sheets, but the disease can also appear on adult leaves. Initially, a small oil stain of any shape appears. In humid weather, a white coating forms on the underside of the spot. Gradually, necrosis occurs on the spots, covering more and more he althy tissues. First, the affected tissue turns yellow, then becomes brownish, the process of drying and dying begins. Those leaves that are most affected fall off. After the appearance of the disease on the leaves, it passes to the crop. When the fruit brush is damaged, it wilts.
In order to prevent grape disease, soil mulching under vines is carried out in early spring, phosphorus-potassium fertilizers are applied in a timely manner, stepchildren are removed and preventive treatments are carried out with fungicides. The first treatment is carried out during the period when the shoots grow to a length of up to fifteen centimeters. The second treatment is carried out before flowering, and the third - during the period when the berries reach the size of a pea. For processing, various preparations offered in garden stores are used. It can be "Strobe", "Horus", Kuproksat" and others.
Powdery mildew, or oidium
Pathogen: Uncinula necator Burril.
In the description of grape diseases there is such a disease as oidium, or powdery mildew. It was brought from North America.
Signs of the disease is a lag in the growth of shoots. This can be seen at the very beginning of leaf blooming, the growth of the vegetative mass. The loose leaves look curly, completely covered with a grayish-white bloom. Inflorescences, clusters look like they were showered with ashes. All affected inflorescences die off. In dry weather, diseased berries dry up, but if the weather is damp, they burst and collapse.
The oidium disease causes great harm to vineyards. The incubation period is one to two weeks. Conidia are able to grow at a temperature of five degrees, but this process is enhanced at 25-35 degrees. In places where ventilation is poor, the plant is most affected.
The fight against oidium involves airing the bushes, weed control, proper pinching, tying the plant. Be sure to treat the vines with fungicides. These can be drugs "Strobi", "Horus", "Topaz", "Thiovit".
Black spotting
In regions with high air humidity, the fungus spreadsintensely, affecting all parts of the plant, including lignified parts of the vine.
Signs of the disease are discoloration of the bark of young shoots and the formation of black dots. They grow and take up more and more space. Gradually, the spots merge into one huge spot, the vine begins to crack, the leaves and fruits are affected.
Black spot is almost impossible to treat. Looking at photos of grape disease, you can see what the disease looks like.
To protect the vine from black spot, it is necessary to carry out preventive treatment of vines. For this purpose, spring treatments are carried out at the time of leaf blooming. For this, drugs such as Ridomil, Antrakol, Bordeaux mixture, etc. are used. After treatment for black spotting, the vines are sprayed against mildew and other diseases. Be sure to carry out the treatment in the fall, after all the leaves fall, with copper contact preparations.
Grey Rot
Protection against this disease is carried out in the spring. Processing of grapes from diseases is carried out from spring to autumn.
Signs of the disease are a brown shade of berries, cracking of the skin, a grayish coating appears. There are practically no effective remedies for the treatment of this disease, but prevention helps a lot to help protect the vine from infection. For this purpose, it is recommended to grow those varieties that are resistant to gray rot. When cultivating grapes, the vines form a standard type, ensuring optimal loads.
During the growing season throughout the entire periodpruning leaves to improve air circulation inside the plant, remove all excess shoots. At the first symptoms of the disease, the affected clusters are removed.
Be sure to treat the foliage with a solution of copper sulphate, diluting it at the rate of twenty grams of powder per twenty liters of water. You can use baking soda at the rate of two hundred grams for two buckets of water.
Chlorosis
With this type of disease, a change in the color of the leaves is observed: they become colorless, pale yellow. The development of chlorosis is promoted by cold water, an insufficient amount of nutrients in the soil, which are necessary for the formation of chlorophyll.
To protect the vines from chlorosis, they are treated with phosphorobacterin dissolved in water, ferrous sulfate is introduced into the soil. In order to prevent chlorosis, it is imperative to carry out bush pruning only with the treatment of wounds with vitriol. In the spring, for the purpose of prevention, they are treated with a solution of iron sulfate in the morning and evening hours. The solution is made at the rate of one hundred grams of powder per bucket of water.
Anthracnose
This disease is fungal. It affects shoots, leaves, inflorescences, berries.
Anthracnose is widespread in Europe, America, Asia. Basically, the disease occurs in areas with a humid and warm climate, as well as in the zone of the Black Sea coast of the Caucasus, in Moldova.
The causative agent of anthracnose overwinters on the affected parts of the vine, can survive up to five years in the form of mycelium, sclerotia and pycnidia. It gives up to thirty generations of spores per season. Spring rainfall causes earlydefeat of developing young leaves and shoots.
Signs of the disease is the appearance of brown spots on the leaves, surrounded by a dark white border, which often merge. Then the affected areas crack, forming deep ulcers. They can affect inflorescences, acquire a brown tint, dry out. Similar clinical signs appear on petioles, ridges, berries. The disease hits vineyards the hardest during the rainy seasons, causing great damage.
Methods of controlling the disease are reduced to the cultivation of anthracnose-resistant grape varieties, as well as treatment with contact systemic fungicides. The terms for processing vines from this ailment are the same as for processing from mildew.
Antracol, Acrobat, Bordeaux mixture, Horus and other drugs are used to combat anthracnose.
Phylloxera
Phylloxera is a dangerous pest of grapes. It is distributed with planting material. The larvae form galls on the underside of the leaves, where they lay eggs that give rise to new generations. Up to ten generations of the pest can develop during the growing season.
The most effective pest control method is to grow varieties on rootstocks that are resistant to phylloxera. Radical methods of dealing with the detection of root phylloxera - uprooting all the bushes in the lesion and in the surrounding area.
Actellic, Aktara, Confidor and other drugs are used to fight diseases.
Spider mite
There are more than two hundred varietiesspider mite, which parasitizes plants, including grapes. This pest got its name due to the ability to weave plants with cobwebs. It can be seen on the underside of the leaves, near the stems.
Ticks feed on the sap of the plant, leading to a decrease in growth and a deterioration in the ripening of shoots. It also reduces the sugar content and increases the acidity of the grapes.
When treating diseases and pests in the spring, be sure to use such drugs that help prevent the appearance of spider mites. These are "Match", "Aktellik" and others. They also carry out the processing of vines when infected with a tick.
Fitoptus, or grape itch
Another type of mites is the grape felt mites. Its appearance is indicated by swollen dark areas on the front side of the leaves, and impressions covered with villi are visible from the inside. At first they are pinkish-white, then they turn brown or reddish. As a result of damage, leaf photosynthesis is disrupted. If the itch affects the inflorescences, then there is a compaction of the petals, a change in color. Subsequently, they crumble. Most often this happens on hybrid producers.
Zuden hibernates under the scales of the buds, at the very base of the shoots, in the cracks of the bark. In the spring, it passes to the kidneys and sticks to them. During the growing season, it gives several generations.
According to statistics, not all varieties are equally affected by this disease. Those infected with phytoptus should be treated immediately.
Processing grapes in the spring from diseases andpests are best done together. This will help prevent dangerous fungal, viral and other types of diseases from infecting the vines, as well as keeping pests out of the vineyards.
To protect against diseases and pests of grapes, acaricides are used: Thiovit Jet, Match, Actellik.
Leaflet
When carrying out seasonal processing of grapes from diseases and pests, the vines must be sprayed.
Leaflet usually damages inflorescences, young ovaries, berries. It can eat not only grapes, but also other plants. The caterpillar of the first generation is capable of destroying up to thirty buds, and the second - about twenty berries. Pathogenic microorganisms develop on damaged buds and ovaries, causing rotting of berries and clusters.
The leaflet can be of different types. The most common: bunch, grape, biennial.
The biennial leaflet is a small grayish-yellow butterfly with a black transverse stripe in the form of a triangle on the wings. Caterpillars about two centimeters long, brown-red. Leafworm pupae are short, less than a centimeter, yellow-brown in color. They have four pairs of hooks at the back end.
Vine leafworm is a caterpillar that causes great harm to inflorescences, grapes. They turn into beautiful brown butterflies with a bluish-brown pattern on their backs.
Grape leafworm is capable of infecting swollen buds, eating leaves, twisting them. It damages inflorescences and berries. Butterflies of thispest species are yellowish in color with three brown stripes. The second pair of butterfly wings is gray or greenish.
To fight pests and diseases of grapes, it is necessary immediately after opening the bushes to clean the old bark along with pests and disease spores. All removed parts of the vine are burned.
Be sure to treat with chemicals. A two-year-old leaflet is treated by spraying two weeks after the start of the summer of butterflies of the first and second generation. After another two weeks, re-treatment is carried out.
To combat grapevine leafworms, the first treatment is carried out two weeks after the start of summer of butterflies of the first generation, the second treatment is carried out after another ten days, the third - after two weeks.
Processing grapes from diseases and grape leaflets is carried out during the swelling of the buds and immediately after they bloom.
Products "Prokleim", "Match" and others are used for treatments.
At the first signs of the disease, you should look at the description of grape diseases with photographs to find out what exactly caused the damage to the vine. But it is better to prevent the spread of diseases and pests, but to carry out timely preventive treatments, remove leaves from under the vines, remove mulch, burn cut branches, bark. All this will help protect the vineyard and stay with a big harvest.
