Diseases and pests of tomatoes in the greenhouse

Tomatoes are one of the most popular vegetable crops grown in greenhouse conditions by gardeners. Experienced tomato growers know firsthand that diseases among this representative of the nightshade family are not so rare.

Depending on the nature of pathogens, the following groups of tomato diseases can be distinguished: fungal, viral, bacterial, non-infectious (caused by damage from pests)... When growing tomatoes in greenhouse conditions, diseases often occur due to a violation of the temperature regime and excessive humidity. The most common diseases of tomatoes in a polycarbonate greenhouse are fungal (late blight, cladosporium, rot).

Spores of microorganisms that can cause disease often persist in the ground and survive the winter safely. Under favorable conditions for the vital activity of bacteria and fungi, they begin to multiply and infect plants.

Even if the land is cultivated or completely replaced, diseases can still occur. For example, they can be brought into the greenhouse with soil after transplanting. Another cause of disease is pests. It is quite difficult to deal with them. They still end up in a greenhouse or greenhouse.

If tomato diseases still appear, in order to combat them, you need to determine which disease you will have to fight with. To do this, it is necessary to study the main types of pathogens. And also a description of the pests of this culture. Then it will become clear how to process tomato bushes.

This type of disease is caused by pathogenic organisms. The cause is poor quality seeds, poor soil, poor seedling care.

There are several types of bacterial diseases developing in the greenhouse.

• Black spot... The disease develops rapidly under favorable temperature conditions (above + 25 ° C) in conditions of high humidity. You can recognize this type of spotting by small black spots surrounded by a yellow border. As it spreads, black stripes become visible on the trunk. Dark spots appear on green tomatoes. They are watery in outline.

• Tomato bacterial cancer. The disease is most often found in tomatoes growing in polycarbonate greenhouses, greenhouses. The first sign of a dangerous (quarantine) disease is twisting and then wilting of leaves. Moreover, the leaves may begin to wither on one side of the plant. Later, brown spots appear on the leaves. Then they die off. There are brown stripes on the stems. Cracks appear, from which mucus flows. The fruits are covered with white spots with a brown dot in the center. Such spots resemble a bird's eye.

When the first symptoms of cancer appear, the diseased bushes are destroyed. The remaining bushes need to be sprayed with copper-based chemicals.

These diseases are caused by fungi. Moreover, some of them can affect not only tomatoes, but also other vegetable crops growing in the neighborhood.

Late blight is the most famous among tomato diseases. The spores of the fungus that cause the infection can be found in the ground, on shovels, pitchforks, and other gardening equipment. You can add fungus to your shoes too. Slugs are also carriers. The causative agents of late blight survive the winter well. In conditions of high humidity and high temperatures, the disease develops rapidly.

Late blight is not a rare guest in polycarbonate or glass greenhouses. Brown spots appear on the underside of the leaves. If you turn the sheet over, you can see a bloom. Flowers dry up and fall off. Later, light brown spots appear on the tomato fruit.

Prevention of late blight - the use of biological preparations... Plants can be cured using chemicals that are sold in specialized stores. Alternative methods of prevention and treatment of plants are also suitable.

Cladosporium (brown or olive spot). Signs of the appearance of cladosporium are yellow-green spots. Later they turn brown. On the spots - terry bloom.

It takes about 2 weeks from the moment of tomato infection to the first manifestations of the disease. And after another month, brown spot can destroy the plant.

Tomatoes at an early stage of the disease are treated with fungicidal agents. In the greenhouse, it is necessary to observe the ventilation mode. It is important to monitor the humidity level (no more than 70%).

The lower leaves on the bushes are neatly broken off and burned. Folk remedies are suitable only at the stage of disease prevention. Cladosporium can destroy about 1/3 of the crop.

Powdery mildew... Often infects tomatoes in greenhouse conditions. Typical signs - a white bloom, reminiscent of flour, forms on the leaves on top. Later, it spreads to the stem. There are spots on the leaves on the underside. The disease affects the tomato from its base.

Macrosporiasis... This disease develops on all parts of the tomato, except for its roots. On the leaves located below, brown spots are formed. Then the disease affects the organs of the plant, located closer to the top. There are brown spots on the stem of the tomato; they are pressed into the tissue of the stem. They resemble burns on foliage in structure. Brownish spots are also formed on the fruit. They appear next to the stalk.

Macrosporiosis retains its viability in the soil for 3 years. They fight the disease by spraying with Bordeaux liquid.

Tobacco mosaic. The disease can reduce the planned harvest by 5 times. The disease is easily transmitted from one plant to another. The causative agents of tobacco mosaic can persist for a long time in greenhouses, in the ceilings of buildings, trellises, and garden tools.

The symptoms of the disease are fruit damage (yellowing) and the formation of mosaic-like stains on the leaf blades. The virus can infect an entire plant. Tomato bushes do not completely die, but their growth is noticeably reduced, development is delayed. In the process of the disease, the fruits become covered with brown spots.

Green tomato mosaic... This virus causes green spots and streaks on young leaves. A viral lesion can manifest itself as leaf deformation. The fruits are also affected.

Affected shoots or bushes of tomatoes must be completely destroyed. If the disease has just begun to manifest itself, fungicidal agents can be used. In the initial stage of the disease, it is quite possible to get by with folk recipes.

Brown (brown) wrinkling... A very dangerous virus.If it gets into the greenhouse, then you can lose the entire tomato crop. Necrotic spots are on peduncles, petioles. Several symptoms appear on the leaves at once. Mosaic and stains are present. The leaves are curled in places. Brown spots form on the fruits of tomatoes, on the surface of which you can notice wrinkling. In this case, the fruits may be deformed.

If the virus appears in the greenhouse, all infected bushes are subject to destruction. It is necessary to carefully observe the cleanliness in the greenhouse, to carry out hygienic measures. Transmission of the virus is possible through contaminated instruments. It can be brought into the greenhouse on clothes or shoes.

Top rot. The disease appears as a result of a lack of calcium and water, damage to tomato roots. Symptoms are brown or dark spots. They are located on the tops of the tomatoes. Spots can grow. The pulp underneath is very dry.

Main reasons - long drought and high air and soil temperatures. To feed the plant with calcium, spraying the leaves with products containing this element is used. It is better to sprinkle a tomato with fertilizers with calcium during the period of fruit setting.

Falling flowers, ovaries. The reason is the poor assimilation of boron and manganese by the plant. This is due to the high acidity of the soil. Lack of potassium and phosphorus also contributes to the development of the disease. The high air temperature in the greenhouse structure can become a provoking factor in the painful state of tomatoes.

Cracking tomatoes... Due to a change in the water level or an insufficient amount of water, tomatoes may begin to crack. And also cracking can occur due to large fluctuations in temperature and excessive amounts of minerals in the soil. To avoid cracking, you need to choose varieties that are resistant to it. Potash fertilization is also a preventive measure.

Potassium deficiency. Uneven color of the fruit can occur due to a lack of potassium.

Insects, slugs, snails can not only spoil the leaves and fruits on tomatoes, but also become carriers of diseases. They easily transfer spores, bacteria, viruses from one bush to another. They make holes in the fruit and carry the infection. Therefore, you need to fight them.

There are several ways to deal with slugs.

• Mechanical method. For this, slugs are collected by hand at night.

• Biological method. A parasitic nematode is used. The slugs are afraid of her. They quickly retreat from the greenhouse in which the tomatoes grow.

• You can also poison slugs. For this, drugs containing metaldehyde are purchased. From folk remedies, you can recommend ammonia or an infusion of onion peel.

In addition to slugs, other pests can also threaten tomatoes in greenhouse conditions. These are the Colorado potato beetle, spider mite, bear, whitefly, wireworm, gnawing scoops. To combat them, insecticides are used, which can be bought at a specialized store.

To get a high yield of tomatoes, it is necessary to avoid the occurrence of diseases. Preventive measures are carried out so that the tomatoes do not get sick. It is necessary to carry out processing of plants in order to prevent the development and spread of pathogens.

For prevention, you can use drugs that increase the protective properties of tomatoes. Sodium and potassium humates are used: 10 ml of potassium humate is diluted in a 10-liter bucket of water. Spraying with such a solution is carried out during the appearance of buds and flowers. In addition to protecting against diseases, the remedy will strengthen the plant's immunity, increase the yield.

Fungicidal agents are used prophylactically to prevent fungal diseases. When the procedure for spraying tomatoes is carried out, you need to make sure that it only gets on the crop.

Some gardeners prefer to do prophylactically "without heavy artillery." There are many natural remedies that can help protect tomatoes from disease without chemicals. For example, a solution of garlic is made and the plants are sprayed. Whey is also used. It is diluted with water. Tomatoes need to be processed every 3-4 days.

Milk is also used, to which iodine is added. For 10 liters of milk, 10-20 drops of iodine are needed. Tomatoes are sprayed with this solution in the greenhouse. This method is suitable for the prevention and control of many diseases of tomatoes. Treatment with a mixture of milk and iodine repels many insect pests.

Ash is also suitable for the prevention of diseases. For 20 liters of water, 6 glasses of ash are needed, a soap solution is added. The resulting product is sprayed on tomato bushes in a greenhouse.

And also a powerful preventive measure will be regular aeration greenhouses.

Assurances from seed sellers that a particular variety is completely resistant to disease is a hoax. There are no such tomatoes. They all can get sick. But there are tomatoes that are highly resistant to a certain group of diseases. Most often these are hybrids. As a result of breeding work, varieties that are resistant or tolerant to diseases appear.

Disease-resistant hybrids with red color of fruits - "Vologda", "Virtuoso", "Bohemia". "Eupator", "Opera", "Ural", "Spartak", "Charisma", with orange - "Firebird", "Diorange", with yellow - "Golden bead", "Yellow date".