Many people think that growing tomatoes in a greenhouse is easy. They are well protected from adverse weather conditions and drying out of the soil.
But even here they can be susceptible to various diseases, and a violation of watering, temperature conditions contributes to the reproduction of pests and microbes.
Diseases of tomatoes and their characteristics can be varied, the main thing is to notice the main signs in time and use various means to combat them. If everything is left to chance, then this will lead to:
- decrease in yield;
- damage to fruits;
- death of tomatoes.
Fungal lesions, photos and methods of treating greenhouse tomatoes
The most widespread diseases are caused by fungi. Their spores begin to wake up in high humidity, because dampness is not easy to avoid in a greenhouse.
Anthracnose is caused by a fungus mainly carried by weeds.
Tomatoes become weak, shedding all the leaves. On ripe tomatoes, small light depressed spots appear, turning into dark rings. Tomatoes burst, an infection trapped inside leads to rotting. Green fruits and soil are infected.
In order to prevent this, it is necessary:
- kill weeds in time;
- control the moisture content of the soil and air;
- spray regularly with special solutions.
With late blight, the lower leaves first turn yellow, dry and die off. The fungus then infects the fruit. They turn black, becoming covered with small spots that increase gradually. You can fight with a tincture of garlic, treatment with a 10% solution of common salt or 1% Bordeaux liquid.
The disease is caused by a fungus that develops when:
- poor lighting;
- low soil moisture;
- high temperature.
The signs of fusarium are:
- yellowing of the leaves;
- wilting of cuttings and shoots;
- slowdown in plant growth.
At the first symptoms, the diseased plant must be removed along with a lump of soil. For treatment, use:
Root rot is caused by fungi that attack the fruit. A small brown spot appears at their base, the plant begins to wither, and green tomatoes still fall.
It is required to disinfect the soil with a solution of copper sulfate. Remove its top layer and add fresh. For processing it is necessary to use the means "Barrier" and "Barrier".
Cannot be fed with fresh manure.
It is also called dry spotting. The disease develops due to excessive watering and poor ventilation. At first, spots from 7 mm to 15 mm appear on the lower, then the middle leaves and stem. A gray fluffy bloom forms on top of the spots. High humidity causes them to drain. Leaves begin to fall off. On tomatoes, depressed round spots with a black bloom near the stalk are formed.
After detecting the disease, you need to use contact fungicidal preparations. Biological agents "Trichodermin" and "Fitosporin" will help in the treatment.
Before buying fungicides, you must carefully read the instructions.
In cladosporium disease (brown olive spot), the lower leaves are affected first, yellow round spots are formed on their upper side. The lower surface is covered with a brown velvety coating. As a result, the leaves gradually curl and dry out.
If left untreated, the disease affects the fruits, which acquire a dark color, become soft, and then dry out.
The reason lies in:
- watering with very cold water;
- a sharp temperature drop.
It is necessary to fight with the help of drugs such as:
- "Bordeaux mixture".
Gradual wilting of seedlings
The reason for the slow wilting of plants can be contamination of the soil with sclerotinosis. In this case, white spots are observed on the leaves, the stem becomes lethargic, the seedlings become discolored and do not develop. It is necessary to change or disinfect the soil.
Didymella can slowly destroy the plant, in which dented black spots and dots appear on the stalk. Fungi are found in infected tops or seeds. Fight didimella by spraying Bordeaux liquid.
In a short time, gray rot can destroy tomato seedlings; its infection occurs through diseased soil.
All bushes are subject to destruction.
It is necessary to adjust the humidity and temperature, also spray with a fungicidal preparation.
Dripping moisture is the cause of powdery mildew. A white flour coating forms on the leaves. They become brittle, curl, dry and fall off. Lack of treatment leads to the death of the bush. The soil needs to be cleaned and cultivated. Chemicals are used to fight.
Description of viral infections with photos
Tomatoes, if planted with infected seeds, can contract viral diseases. Since there are no effective control methods, you need to hold them in a 1% manganese solution before planting. You also need to disinfect the soil - 2-3% of the same solution.
A bush that suffers from aspermia does not develop correctly. It looks like corrugated paper in appearance. Its color is randomly patterned. Fruits are few, they are small.
Leads to necrosis:
- lack of light;
- abundant watering;
- excess nitrogen fertilizer.
The first signs are the appearance of small dark-green cracks on the lower part of the stem, later in them sprouts of air roots are formed. Then the leaves wither, the plant falls and dies. The fruits on it do not ripen.
The danger of this disease is that there is no treatment, prevention is needed. The reason is the use of contaminated seeds and planting seedlings in diseased soil. The symptom of the mosaic is a patterned color in the form of dark and light green intensely increasing spots.
As soon as they appear, the bush must be pulled out and disposed of, and this place must be treated with a special solution.
Often tomato diseases in a greenhouse are provoked by bacteria. The culture is affected by the infection in a short time. There is no way to save the harvest.
Bacterial black spot affects all aerial parts. The appearance of tomatoes deteriorates. If the soil is infected, all seedlings may die. Symptoms of this disease are raised 3 mm black dots with a watery edge. They gradually increase, begin to press inward, and the edges break. The tomatoes rot under these spots.
Infected residues and untreated seeds lead to contamination.
To avoid bacterial diseases, you need to use alternation; tomatoes can be planted in their original place after 2-3 years.
The first signs are visible after fruit formation, the plant withers, leaves and fruits become stained. The vascular system of the plant is affected, which becomes dark. Cancer is caused by contaminated seed and bacteria.
The fight is to decontaminate the seeds. The temperature in the greenhouse should be about 25 degrees, and the humidity should not exceed 60%.
Harm to tomatoes:
- Medvedka. Has a gray color. This 50 cm insect has pronounced digging legs and short elytra. She digs deep nests, where she lays about 300 eggs. A tincture of 150 grams of hot pepper and 10 ml of water poured into the mink will help to get rid of.
- Wireworm. These are yellow caterpillars 20 mm long, which infect the root, penetrating the stem. They need to be collected by hand, and also sprayed with a special preparation.
- Scoop. This is what moths are called. Their caterpillars are black and earthy gray in color, eating up leaves and stems. You can fight them with an infusion of garlic or burdock leaves.
- Whitefly. The yellowish whitefly completely covers the leaves, on which a black bloom appears. They dry up, and the plant dies. It is necessary to fight the larvae. For this, the leaves are washed with soapy water. Dandelion infusion helps a lot.
To preserve the tomato crop in the greenhouse, it is necessary to start treating diseases in a timely manner, and it is best not to forget to engage in prevention. It is much easier to fight when fungi, bacteria or viruses have just begun to develop.