How to treat powdery mildew tomatoes: control measures

Powdery mildew on tomatoes is a common name for fungal diseases that are characterized by a white, powdery coating on leaves and stems. The main pathogens are marsupials Oidium erysiphoides and Oidiopsis taurica.

Oidium most often affects greenhouse tomatoes with insufficient watering and low relative humidity. In the open field, the disease is possible, but does not carry such serious consequences and is easier to treat.

The first signs of the disease are rounded yellowish spots on the leaves at the bottom of the bush.On the reverse side, a white powdery coating is visible. Over time, the spots merge and the plaque moves to the upper parts of the leaves and stems. Fruits affected by powdery mildew crack and rot.

To minimize the risk of powdery mildew on tomatoes, the following rules must be followed:

regular cleaning of the site from weeds, rotten fruits and other plant debris;
compliance with the rules of crop rotation on the site and the annual replacement of soil in the greenhouse;
Planting no more than 3-5 bushes per square meter, forming bushes, tying to supports, removing excess shoots and leaves that interfere with air circulation;
timely feeding of tomatoes with mineral fertilizers without exceeding the permissible dosages (especially nitrogen);
timely watering;
regular ventilation in the greenhouse;
daily planting inspection for early detection of infected plants;
prophylactic treatment of tomatoes with biological products;
timely treatment of infected plants with chemicals.

How to deal with powdery mildew on tomatoes?

At the first signs of infection of tomato plantings with powdery mildew, it is necessary to react quickly and treat the plants in the first 3-4 days. Fungal infections are easier to treat in the early stages before tissue necrosis has occurred.

If measures are not taken to control powdery mildew on tomatoes, mushroom colonies spread rapidly. The leaves dry up and fall off. The plant will try to start new shoots, but under the influence of infection, they will also die quickly.

It is wiser to carry out preventive spraying of tomatoes 2-3 times a month with safe biological preparations or formulations from folk practice.

Folk remedies

Before you treat powdery mildew tomatoes with chemical fungicides, you can try to treat with folk remedies. The main thing is to have time to spray the tomatoes in the first 3-5 days after infection.

Soap and soda solution

In 10 liters of hot water, stir 2 tablespoons of soda and 10 g of laundry soap. All tomatoes are sprayed with a cooled solution when the first signs of infection appear in the beds. After 2-3 days, the treatment is repeated.

Whey

Whey is diluted with water in a ratio of 1:10 and sprayed on tomatoes in dry weather. Dried on the leaves, the serum forms a protective film and prevents the development of the fungus.

Whey is a safe and effective prophylactic against powdery mildew. Spraying the plants once every 2 weeks will help to avoid infection. The initial form of the disease is treated with a course of 3-4 treatments with an interval of 2-3 days.

Wood Ash Infusion

Wood ash is poured with hot water in a ratio of 1:10, stirred and infused for a week. The water is carefully drained without sediment and the tomatoes are sprayed with it. Processing tomatoes with an ash solution is an additional foliar top dressing with minerals.

Manganese solution

2.5 g of potassium permanganate is dissolved in a bucket of water and the tomatoes are sprayed every 5 days until the signs of the disease disappear.

Bioactive substances

Not all measures to control powdery mildew on tomatoes are equally safe for treated plants, humans and the environment. If the disease is not advanced, then it is better to use harmless bioactive substances.

Humate Na

Sodium humate solution (0.01%) is suitable for the treatment of tomatoes in the initial stages of infection with powdery mildew and for preventive treatments.

Spraying once every 10-14 days at the first sign of disease stops the spread of the fungus.

Important! Humate, being a growth stimulant and complex fertilizer, helps plants to get stronger and recover from illness.

Thiovit Jet, Cumulus DF (colloidal sulfur)

Bioactive substance colloidal sulfur disrupts the vital processes of mealy fungi cells. The result is visible the very next day after treatment and retains a protective effect for another 10-14 days.Subject to the recommended dosage of 30-80 g per 10 liters of water, remedy is safe for plants. Tomatoes are processed 1-5 times per season.

Biologicals

Sprinkling tomatoes with biological preparations, you can not only cure plants from fungi, but also further strengthen their immunity.

Baktofit

Treatment with the biological preparation Bactofit should be carried out as a preventive measure and at the first symptoms of infection with powdery mildew. It is harmless, is a good growth stimulant and increases yield by 10-20%. Bactophyte can be used in conjunction with chemical herbicides to reduce the likelihood of burns and restore plants.

Planris

Planriz is not registered, but is widely used by vegetable growers to combat fungi, including powdery mildew of tomatoes. This biological agent treats the disease in the initial stages and is suitable for preventive spraying. Processing is carried out every 10-14 days. Planriz is suitable for tank mix when needed.

Bordeaux liquid

Processing with Bordeaux liquid can only be carried out on cool, dry days so as not to leave burns on tomato leaves. For preventive spraying, a 1% solution concentration is suitable. When signs of fungus disease appear, treatment is carried out with a 3% solution of Bordeaux liquid. Copper in the composition of the solution has a positive effect on plant growth and ovary formation.

Chemical fungicides

Chemical fungicides can harm pollinating insects and cause fungal resistance when used frequently.

Advice. Do not treat tomatoes with chemical fungicides more than 2-3 times per season and try to change the active ingredients.

Silicate glue is usually added to solutions for better adhesion of the drug. When spraying, a fine spray mode is selected to prevent the substance from running off onto the soil. In the greenhouse, not only plants are treated with fungicides, but also structures of the structure.

Quadris

Quadris belongs to the class of strobilurins. In calm, dry weather in the evening or morning hours, tomatoes are treated with a 0.2% fungicide working solution. Do not allow the product to drip onto the ground. The number of treatments per season should not exceed two.

Topaz

Topaz belongs to the class of triazoles. Active against powdery mildew on tomatoes and other fungal diseases.Topaz is able to penetrate through young shoots into the plant and act systemically in all parts of the bush. The activity of the drug is maintained for two weeks.

Privent, Byleton

Privent and Bayleton belong to the group of triazole derivatives. The active substance is triadimefon. Broad spectrum fungicide. If signs of infection with powdery mildew are found, the plants are treated with a 0.1% working solution.

Triadimefon penetrates into the tissues of tomato bushes and stops fungal cell division. The effect of the drug is noticeable already on the first day after treatment and lasts up to 3-4 weeks.