What are fungicides for grapes: types, how to use

Grapes are often affected by various fungal diseases, which are not always curable. Therefore, regular treatment of the vines with fungicides—chemicals used to suppress infections—is recommended. All pesticides contain active ingredients that block the vital functions of pathogens and cause their death.

Fungicides for grapes

All modern medicinal products are divided into three large groups according to their mode of action:

1. Contact.
2. Systemic.
3. Complex.

Each product has its own working algorithm. The effectiveness of a fungicide depends on the time of the grapevine's growth stage and the stage of the disease. If the disease has not yet affected the grapes, certain products are used, while others are used when infection foci appear.

Contact

Products in this group should be used as a preventative measure, as they are not able to combat the disease once it has already appeared. Contact fungicides are reliably protect healthy plants During a rampant infection in the garden. The main advantage of contact fungicides is that plants do not develop immunity to them, so beneficial spraying can be done several times (3-6 times) per season. The disadvantages of such fungicides include their short duration of action—they protect plants for about 10-12 days, after which they must be re-treated. Furthermore, plants should be re-sprayed immediately after rain, as precipitation easily washes the product off the leaves.

Contact pesticides work by preventing their active ingredients from penetrating the plant, creating a protective film on the surface that prevents fungi, viruses, and bacteria from penetrating. Because the entire mass remains on the plant's surface, these pesticides are also called local pesticides. Treatment must be thorough, as if even one untreated area remains, the infection will quickly take advantage of the situation and penetrate the stem. All above-ground parts of the plant—stems, vines, leaves, and trunks—are sprayed.

Fungicide treatments begin as early as possible, usually at the very beginning of the season, before infection has even appeared in the garden. Thorough spraying of grapes is carried out before bud swelling. Copper-containing solutions should not be used during flowering, as this element can accumulate in various parts of the plant.

Systemic

If the infection has already penetrated the plant, systemic fungicides are used for treatment. Their active ingredients readily penetrate plant tissue, from where they act on the pathogen. The active ingredient begins combating the pathogen immediately upon entering and reaching the source. The treatment blocks the fungus's ability to reproduce, preventing the pathogen from growing and eventually killing it completely. Systemic fungicides can be used at all stages of plant development and disease progression. Their duration of action is virtually unaffected by weather conditions, as they are not washed away by precipitation or evaporated by sunlight.

However, this depends on the fungus's immunity and its rate of reproduction. Typically, the therapeutic effect lasts for 2-3 weeks, after which the treatment should be repeated. However, overuse of harsh chemicals is undesirable, as this can lead to plant suppression. A weakness of systemic treatments is the rapid tolerance of pathogens to them. Therefore, repeated treatments with them are not advisable, as this will be ineffective. It is recommended to alternate fungicides containing different active ingredients.

Complex

These products are also called combination products, meaning they combine the properties of contact and systemic fungicides. While highly effective in combating rampant disease, combination products are not without their drawbacks:

• they are toxic to humans and animals;
• they cannot be used during the fruiting and ripening period;
• Most medications can combat a specific type of fungus.

The most popular drugs

Each fungicide “works” in its own direction, treats certain diseases and affects the fungus in its own way. Therefore, it is first necessary to determine the specific disease the grapes are affected by, and then select the most appropriate treatment for that specific condition.

Strobe

Operating principle. A systemic fungicide whose effectiveness lies in the rapid penetration of its active ingredient into plant tissue, attacking the pathogen from within. Synthetic strobilurins (a member of the fungal family) used in the formulation inhibit the viability of the pathogen, thereby preventing the growth of mycelium and secondary spores. The product is used to combat fungal diseases, particularly mildew and oidium.

Peculiarities. Strobi is popular due to its effectiveness and low toxicity. It doesn't accumulate in soil or water and is harmless to bees. Furthermore, repeated spraying doesn't harm the plants themselves—it can be applied even during flowering. The product isn't washed away by precipitation. It can be used at temperatures down to -4 degrees Celsius.

How to apply. During the season, Strobi treatment is carried out 2-3 times. The first preventive spraying Apply in the spring, when the buds are swelling. The treatment can then be repeated before and after flowering. The product is available as water-soluble granules. To prepare a working solution, dissolve 2 grams of powder in 6 liters of water. Spray all areas of the shrub with the resulting mixture.

Quadris

Operating principle. A Swiss product designed to inhibit fungal reproduction. Its active ingredient, azoxytrobin, is a strobilurin. Upon application to the affected area, the product immediately begins to attack all harmful pathogens indiscriminately (especially those causing mildew, powdery mildew, and downy mildew), while sparing beneficial microflora. This makes Quadris suitable for use against all fungal diseases.

Peculiarities. The fungicide's components are harmless to flora and fauna. They decompose quickly in the soil and do not accumulate in the berries. The medicinal liquid accumulates only in the leaves, while it practically does not penetrate the stems and fruits. The protective and therapeutic effect lasts up to 21 days. Quadris's effectiveness is not limited by weather conditions. It is highly effective at temperatures ranging from 4 to 30 degrees Celsius.

How to apply. Fungi quickly become accustomed to the product, so it should be applied to the same area no more than twice, with an interval of 10-14 days. It is recommended to alternate it with fungicides of a different chemical base. Quadris is available as a suspension in 6 milliliter and 1 liter containers. To prepare a working solution, dilute 60 milliliters of the suspension in 10 liters of water. One liter of the prepared solution is sufficient to treat one square meter. As a preventative measure, vines are sprayed before flowering and again after harvest. Treatment with Quadris should be stopped 16-20 days before the fruit ripens.

Skor

Operating principle. This fungicide treats grapevine diseases such as powdery mildew, rubella, rot, and Phomopsis. Its active ingredient, difenoconazole, is a triazole. This substance is fully absorbed by all parts of the plant and acts on fungi by direct contact. It inhibits their development, thereby halting mycelial growth, completely eliminating the possibility of secondary infection.

Peculiarities. Skor penetrates plant tissue within two hours of application. Its duration of action is unaffected by rain or wind. Air temperature can affect its effectiveness – Skor is most effective at temperatures between 14 and 25 degrees Celsius; otherwise, its therapeutic effect is weak. Protection lasts for 7-10 days, after which the application must be repeated.

How to apply. The product is a liquid, available in ampoules or vials. To treat grapes, 5 milliliters of the product and 10 liters of water are required. The working solution consumption is 500-800 milliliters per plant (no more than one liter). The maximum number of treatments is four.

Topaz

Operating principle. A single-component product whose active ingredient is penconazole. When applied to the mycelium, penconazole completely inhibits the fungus's activity, preventing its spores from growing. After a period of time, the spores die within the plant. Topaz is most effective in the early stages of the disease, quickly suppressing primary infection. It is effective against diseases such as powdery mildew, rust, and downy mildew.

Peculiarities. The active ingredient is instantly absorbed into the leaves and stems. It is not washed away by rain or wind. Its effectiveness remains unchanged with temperature fluctuations. Spraying can be carried out at temperatures down to -10°C. The product remains effective for 14-18 days.

How to apply. To prepare a therapeutic solution, stir 2 milliliters of the emulsion into 10 liters of water. For severe infections, treat the vines twice a season, alternating with contact fungicides.

Falcon

Operating principle. A complex systemic fungicide. It consists of two active ingredients (spiroxamine, tebuconazole) and one auxiliary (triadimenol). These ingredients cause tissue destruction and rapid death of pathogens. Highly effective against powdery mildew.

Peculiarities. Falcon, compared to its analogues Topaz and Horus, is less expensive, is practically harmless to humans, animals and plants, and does not cause addiction in pathogenic microorganisms.

How to apply. To prevent powdery mildew and oidium, prepare a solution of 3 milliliters of the product and 10 liters of water. The older the plant, the higher the concentration. When symptoms appear, prepare a therapeutic solution of 6-10 milliliters of the suspension and 10 liters of water. The approximate consumption of the prepared solution is 100 milliliters per square meter. The maximum number of treatments is four.

Fundazol

Operating principle. A systemic medication based on benomyl, which is absorbed into the leaves and stems, treating the disease from the inside out. The active ingredient destroys the cell nuclei of harmful microorganisms. Part of the suspension remains on the surface, forming a white, oily coating. Fundazol is used to prevent and combat leaf spot, various rots, powdery mildew, and root infections.

Peculiarities. The product simultaneously performs two functions: heals and protects the plant Fungal growth prevention. Fundazol is effective in any weather, lasting up to 10 days. It can also be used as an insecticide, killing aphids, whitefly eggs, and leaf beetles.

How to apply. The product is available as a white powder with an unpleasant odor. Frequent use of Fundazol can cause pathogen resistance, so it is recommended to apply the pesticide every two years. Plants should be treated with the fungicide no more than twice per season. One plant is sprayed with a solution consisting of 10 grams of the product and 10 liters of water.

Thiovit Jet

Operating principle. The product contains 80% sulfur, which has a negative effect on various fungi and harmful insects. It is a contact product, meaning the medicinal solution coats all areas of the plant with a film, treating them directly from the outside. When applied to the infected areas, the sulfur damages the pathogenic cells, causing their death. This product is effective against downy mildew and mildew.

Peculiarities. Thiovit Jet is effective at a specific temperature: between 20 and 28 degrees Celsius. Under optimal environmental conditions, Thiovit lasts up to 10 days, providing plants with reliable protection. It is also noted that Thiovit does not cause tolerance in microorganisms, and therefore can be used annually.

How to applyThe product is available as a granular powder that dissolves easily in water. A working solution consists of 40 grams of powder and 8-10 liters of water. The resulting mixture is enough to treat 2-3 bushes.

Shavit

Operating principle. The fungicide consists of two components. It combats various fungal diseases (powdery mildew, gray mold, mildew, white rot, and fungal infection). When applied to the plant, Shavit disrupts the pathogens' activity, preventing the disease from progressing.

PeculiaritiesThe advantages of Shavit include: lack of resistance, long-lasting action (up to 16 days), safety for birds and animals, and harmlessness to plants.

How to applyThe powder, in the form of fine granules, is dissolved in water (0.2 grams per bucket of water). The first treatment is carried out before flowering; it is preventative. The bushes are then sprayed when sporulation appears. The procedure is repeated 2-3 times at two-week intervals.

Cuprozan (copper oxychloride)

Operating principle. A German chemical product developed for treating plants against fungal infections. Cuprozan is a mixture of copper oxychloride and zineb. It acts on the pathogen by contact and combats a variety of harmful organisms.

Peculiarities. Cuprozan has moderate toxicity. It copes well with all grapevine diseases. It can be used as a preventative measure against vine infections in the summer.

How to applyTo prepare a spray solution, dilute 40 grams of the product in a bucket of water. The application rate is 6 liters per 10 square meters. The fungicide can be used at all stages of plant growth. Up to six applications can be made per season.

Convertible top

Operating principleThe product contains the active ingredients metiram and pyraclostrobin. Pyraclostrobin penetrates deep into plant tissues and cells, inhibiting fungal growth. It also acts as a protective barrier for plant cells. Metiram attacks the infection from the outside.

PeculiaritiesCabrio Top is effective for 18-20 days. It can be used for both prevention and treatment. It is not washed off by rain. It is low-toxic to microorganisms and plants, but is dangerous to humans. It is used to treat anthracnose, mycosis, and escoria.

How to apply. Treatment is carried out during flowering and fruit set. The application rate is 0.2 grams per square meter. The frequency of treatment is up to three times.

Paracelsus

Operating principle. A combination fungicide. It treats and protects plants from fungi and regenerates damaged tissue. The active ingredient is flutriafol. This component immediately begins to affect the mycelium, destroying pathogen cells with its vapors.

Peculiarities. The pesticide's protective period is up to 35 days. It is non-toxic and does not cause resistance to fungi. It protects plants both internally and externally. It combats grape diseases such as powdery mildew and downy mildew at any stage of their development.

How to apply. To treat one hundred square meters of grapevine, dissolve 5 milliliters of the suspension in 5 liters of water. The first treatment is carried out before flowering, as soon as the first disease spots appear. Repeat treatments are applied during fruiting.

Polychom

Operating principleA complex fungicide. Highly effective against mildew. It consists of two active ingredients: polycarbacin and copper oxychloride. In addition to affecting the mycelium, these substances also repel certain insects.

Peculiarities. This product has a highly protective effect. It combats all types of fungal diseases. It is rainproof and can be applied at various stages of plant development. It is compatible with pesticides and is non-toxic to pollinating insects.

How to apply. Up to four treatments can be carried out per season. The first treatment is carried out before flowering, and the second after flowering, until the crop begins to ripen. The recommended application rate is 30 grams per 10 liters of water.

Acrobat

Operating principle. A new-generation systemic and contact product. It works both inside and outside the plant. Acrobat's two active ingredients, dimethomorph and mancozeb, destroy fungal spores and build a protective barrier against pathogens.

Peculiarities. This product has long-lasting therapeutic and protective effects. It is safe for the environment and humans and is compatible with other chemicals. It is highly effective at temperatures ranging from 17 to 25 degrees Celsius.

How to apply. The product is sold as a granulated powder in 20-gram, 1-kilogram, and 10-kilogram sachets. To prepare a solution, dilute 20 grams of fungicide in 10 liters of water. The prepared solution can be used to spray up to 100 square meters. This solution can be applied 2-3 times per season.

Preventive measures against fungal diseases

Unfortunately, once the disease has begun to spread throughout the vine, it can be very difficult to cure. Therefore, preventative measures are recommended, including preventative inspections of all areas of the vine, beneficial spraying, and soil treatment.

Regularly inspect the vines and leaves, promptly removing any rotted or dried-out areas. The first preventative spraying should be done immediately after removing the winter cover, before the buds begin to swell.

Sanitary pruning will allow the plant to focus its energy on growing healthy shoots. Removing excess branches that crowd the bush will allow better air circulation, significantly reducing the risk of excess moisture and fungal growth. It's also important to keep the soil clean: promptly remove weeds that carry infections; and loosen the soil to saturate it with oxygen. apply fertilizersto increase the immunity of grapes.

Conclusion

You should also remember the processing rules:

• All spraying is carried out early in the morning in calm, dry weather;
• During processing it is necessary to use protective equipment;
• You cannot treat plants while the fruits are ripening;
• If poison gets on the berries, they can only be eaten after 2-3 weeks.

When applying fungicidal treatments, carefully read the instructions. Concentrated pesticides may not only fail to suppress the infection but also kill the plant itself.