Anthracnose on grapes: treatment and control measures, how to process folk remedies

In a short time, an entire vineyard can die from anthracnose on grapes. Previously, winegrowers in the southern regions, where the climate is humid and warm, had to deal with this scourge. Now the problem is increasingly encountered in regions with a temperate climate. Hybrids (varieties) with high resistance to oidium, mildew are predisposed to the disease.

Signs of anthracnose

In advanced form, anthracnose grape disease affects the entire plant. Constant monitoring is required to avoid crop loss. Young leaves are the first to suffer.Small dark dots form on their surface. They quickly increase in size, turning into spots.

The color of neoplasms on the leaves is brown, the edges are darker. Because of these spots, the disease is popularly called spotted anthracnose. The affected surface may cover the entire area of the leaf plate, its color becomes dirty pink over time.

Sick leaves eventually dry up and fall off, the infection spreads further, passes to the shoots. Brown spots appear on them, which grow in breadth and depth, becoming dark brown. Cracks appear at the sites of injury. If the days are dry and hot, diseased shoots dry out and break. In rainy weather, they begin to rot.

On berries, the infection appears as round, concave spots. Their main color is brown, only the central part is purple. Sick berries dry up, crumble.Anthracnose on the hands can be seen before the flowers bloom. Spots appear on them the same as on the shoots. The part of the brush located below the spot dies. The one above continues development, but does not give a harvest, as the ovary falls over time.

Causes of disease

The causative agent of anthracnose is a fungus of several types: Kabatiella, Gloeoporium, Colletotrichum. All its varieties are very tenacious, they are not afraid of cold snaps, spores hibernate on plant debris and on diseased vines.

A fungal infection may not manifest itself for years, but it can provoke its onset:

wrong cut;
mechanical injury to shoots;
bad weather (rain, hail);
soil acidic, saline;
lack of phosphorus, potassium in the soil.

Favorable environment for active reproduction of the fungus - high humidity, soil and temperature from 23 to 35 °C.

How to fight and how to treat

Only systemic infection control guarantees the salvation of the vineyard from anthracnose. Do not give up when symptoms of the disease appear. You can fight the fungus. You just need to know how to treat a diseased vine. Symptoms of anthracnose appear in the spring, you need to treat immediately, all activities must be carried out before mid-summer.

Agricultural activities

Agrotechnical measures - the first way to treat anthracnose. It is especially effective if the vineyard area is small, each vine can be processed:

cut out diseased brushes;
cut the leaves;
shoots with traces of the disease cut off, grabbing up to 4 cm of a he althy area.

All cuttings should be poured into a bag of polyethylene, you can not throw it on the ground, this can lead to the further spread of the fungus. After the completion of sanitary work, all plant debris must be burned.

To reduce fungus activity, reduce watering. As a result, the topsoil (1 cm) becomes dry. Aisles are cleared of weeds, this also reduces moisture in the root zone. The final stage is top dressing. To increase immunity, phosphorus-potassium fertilizers are applied.

Drugs

Now there are no problems with the acquisition of effective drugs for the fungus. Vine growers prefer biological means. They work well against the fungus, do not harm the environment (insects, soil), are safe for humans and pets.

Popular drugs against anthracnose:

Plantriz;
"Gaupsin";
Mikosan.

Preparations from this list have been tested in practice by many growers. There was no effect on the quality of the crop (taste, composition).A positive effect on the formation and growth of shoots was noted. After treatment, the plants quickly restore the amount of green mass. Treatment with these drugs is carried out every 2 weeks.

Fungicides

In advanced forms of the disease, systemic fungicides against anthracnose are used. According to reviews, good results are achieved with the use of "Ridomil", "Fundazol", "Acrobat". Vineyards can also be treated with other preparations:

Bordeaux blend;
Fitosporin M;
"Trichodermin";
DNOC.

The vineyard is treated in the spring, when the shoots have just begun to grow and do not exceed 10 cm. Treatments with a fungicide solution are carried out only in the evening and morning. This avoids sunburn of the leaves.

Folk methods

Any experienced grower will say that treatment with folk remedies will not give positive results if signs of anthracnose appear on the leaves and shoots, brushes. Spraying the bushes with soda, kefir, potassium permanganate and other similar means is pointless.

No need to be afraid of chemistry, only modern drugs will help to cope with a harmful fungus. Biological agents, systemic fungicides and agrotechnical measures are the only correct ways to deal with anthracnose.

Prevention

A well-maintained vineyard is less likely to suffer from anthracnose. The main preventive measures: timely and correctly carried out sanitary and formative pruning (spring, autumn), in the summer - pinching. A neglected, thickened vine is more likely to suffer from fungus.

All work in the vineyard is carried out with a clean tool processed in a solution of potassium permanganate. Leaves and shoots can also be sprayed with the same composition before processing. In spring, prevention is carried out in several stages:

first stage before flowering - spraying with Bordeaux liquid (1%);
second stage two weeks later with copper oxychloride solution.

Good protection against anthracnose sulfur powder. For prevention, they pollinate the vineyard in the spring. After summer thunderstorms, heavy rains, the bushes are sprayed with a fungicide or Bordeaux liquid.

Autumn maintenance work:

fertilization (potassium, phosphate);
sanitary pruning of diseased, damaged shoots, their destruction;
raking and destroying all leaves;
treatment of row spacing (loosening);
covering the soil with mulch.

Most affected varieties

Mildew resistant variety may be more likely to suffer from anthracnose. Experienced growers have found that the varieties most susceptible to disease are:

Hussein;
Isabella;
Karaburnu;
Lydia.

Of the varieties of the old selection are relatively resistant: Riesling, Chassela Belaya, Saperavi, Cabernet Sauvignon, Nimrang, a hybrid form of Viorica. Modern selection does not stand still. There are new varieties and hybrid forms of grapes, the resistance of which to anthracnose in the scientific literature is not yet known.

The choice of grape variety (hybrid) affects the he alth of the vineyard, but in practice, resistance to the fungus does not always correspond to the declared by breeders. Only basic knowledge of vine care and preventive measures will help to save the harvest.