What is sick of tomatoes in the greenhouse and how to treat them?

Every vegetable gardener who grows tomatoes in a greenhouse faces their diseases. But, unfortunately, not many know how to correctly diagnose infections and lesions, and then carry out effective treatment. In this article we will look at the most common problems, as well as solutions.

Cracking tomatoes

In fact, the appearance of cracks on the tomato peel is not a symptom of a disease, but the result of improperly growing a vegetable. However, cracking fruit is a fairly common disease of tomatoes in the greenhouse. Through these cracks viruses, infections and fungi penetrate into the plant. Causes of cracking:

• overheating of the vegetable,
• frequent abundant watering that flush minerals from the soil;
• sharp wetting of dry soil when water increases the internal pressure in the vegetable, and it bursts;
• kinks in the fight against bushiness;
• nutritional deficiency, a sign of which is yellowing and dying off of the foliage;
• overdose of fertilizers, especially nitrogen.

To prevent such a disease, tomatoes, especially those grown in polycarbonate greenhouses, Observe the following guidelines:

• Choose varieties unpretentious to watering.
• Protect the bushes from the scorching sun with a scattering grid, thrown on the greenhouse, or lime jelly, covering them with the inner side of the glass.
• Observe the uniformity of moderate watering, especially at the beginning of the ripening of vegetables. Their regularity depends on soil moisture, which, among other things, is influenced by weather conditions. In the heat, water in the early morning or late evening, and in the cool it is better to water in the afternoon.
• Ventilate your “warm garden” regularly, especially in hot weather, creating a draft on quiet days, or opening only one “leeward” butt on windy days.

Fungal diseases

Frequent uninvited guests in greenhouses where tomatoes are grown are fungi, and the fight against the diseases they cause requires a systematic approach.

Usually spores of fungi penetrate into the wounds or into the natural openings of vegetables, instantly striking them. This also contributes to excessive planting density.

Late blight

Late blight is the most common plant disease. High humidity and temperature extremes favor its occurrence.

Symptoms of late blight:

• the appearance of black or brown spots with arachnoid bloom, which quickly cover the entire leaf, after which it dries and dies;
• the appearance of spots on the berries.

Disease prevention: careful watering under the roots (possible through PET bottles with a cut off bottom and side opening, dug near the stems), weekly spraying with serum of cow's milk or inorganic fungicides.

Gray rot

Factors for the development of infection - cold rainy weather, poor greenhouse ventilation.

Symptoms:

• the formation of gray spots on foliage and flowers;
• spots are initially dry, and then lizlyly, in a matter of hours (usually at night) spread to the whole bush in the form of a gray bloom.

Lesions are various wounds. Prevention of infection:

• maintaining heat in the "covered garden", as well as its airing to reduce the humidity of the air and the ground;
• carrying out cultivation works in dry, calm weather in the morning, so that the wounds could heal by the night.

Brown spot

Symptoms of cladosporia (also called brown spotting) appear gradually. First, yellow spots appear on the upper side of the foliage, which, growing, merge into one large spot; the lower side of the leaves is covered with brown velvet, spores of the fungus.

The process ends with their twisting and drying. This disease appears during the flowering period of tomatoes (especially if they grow in the greenhouse) or the formation of the ovary and spreads from the bottom up.

Early infection is most dangerous, since long daylight hours and high humidity, which is so necessary for the young, contribute to the development of the fungus. The berries themselves are rarely affected, but if this happens, they also become brown and soft, gradually drying out.

Treatment:

• before treatment, remove the affected leaves and then sprinkle (especially in the lower part of the bush) with a warm solution of milk and iodine (15 drops of iodine and two glasses of milk for half a bucket of water);
• spraying the plant and watering the land with iodine chloride solution (40 drops of iodine and two tablespoons of potassium chloride per bucket of water);
• the use of broad-spectrum fungicides or copper sulfate solution.

Fighting disease:

• regular, alternate spraying of tomatoes in the greenhouse with a pale pink solution of potassium permanganate and ash decoction (two glasses of ash per bucket of water);
• spraying with a weak solution (1:10) of whey.

Fusarium

This is one of the diseases of the leaves of tomatoes cultivated in the greenhouse. The fungus that causes this disease is activated in the heat, especially if the seedlings are weakened due to the low nutritional value of the soil, and there is a frequent change of rainy and hot days on stable cold nights. Excessive bushiness, “generous” top dressing, increased soil moisture or, conversely, insufficient watering, long nights, and poor greenhouse lighting also favor the reproduction of the fungus.

Symptoms of Fusarium Wilt:

• deformation of primordial stems;
• yellowing, drying out and rapid dying off of the lower tier of the foliage;
• wilting the whole bush.

Unfortunately, if the vegetable is affected by Fusarium, it will not be possible to cure it, since the fungus develops in its internal tissues. It remains only to pluck up a bush and burn.

Fusarium Prevention:

• mop-up in the fall;
• deep plowing and disinfection of land before sowing or planting;
• seed disinfection with fungicides;
• staking with a clean tool;
• regular hilling

Macroscopic

Macrosporia is brown or dry spotting that affects the leaves and stems, and sometimes the fruit. It spreads from the bottom up: on the foliage appear concentrations of round brown spots, which gradually grow, merge, after which the foliage dries out. On the stem, such spots (oval) cause rotting and fading.

Fruits, usually stems, appear dark dents, on top of which a dark "velvet" is formed - spores of the fungus. The best conditions for the development of the disease: heat (+ 25 ... +30 ° C) and high humidity. The spores persist on the remains of plants and in the ceilings of the room and spread with the wind and drops of condensate.

Prevention:

• seed disinfection before sowing;
• before the appearance of the ovaries, treatment of bushes with copper-containing fungicides;
• the alternation of crops in the greenhouse, which should not participate solanaceous and cabbage;
• complete destruction of plant residues;
• fertilization with potash fertilizers.

Treatment: before the beginning of fruiting - treatment with antifungal drugs, and in later periods - with biological preparations. Spraying is repeated every two weeks at least three times per season.

Alternaria

This disease manifests itself in the form of dry, dark brown (or black) concentric spot on the leaves and stems, the tissues of which in the area of ​​the spots become covered with olive velvet, and eventually die off.

The fungus, wintering quietly on plant debris or on seeds, penetrates into the ovary in the spring and develops inside the fruit throughout the season, turning its core into a prelum.

Combating Alternaria:

• deep digging of soil in the fall;
• seed disinfection before sowing;
• timely detection of symptoms at the beginning of growth and spraying fungicides three times a month;
• the destruction of insect vectors spore (cicadas, ticks, aphids, etc.);
• during the harvest destruction of the affected specimens.

Vertex Rot

• This pathology is not an infectious disease. This is a physiological disorder caused by poor care: irregular watering;
• at the beginning of the growing season, calcium deficiency (in vegetables, but not in the soil), caused by an excess of heat in the greenhouse;
• overfeeding plants with nitrogen.

The lesion affects only the berries - they form black dents at the bottom, which eventually become watery, increase in size and begin to rot. The latter circumstance is dangerous because rot can strike healthy "neighbors."

Unfortunately, vegetables affected by top rot cannot be cured - they just need to be removed and discarded.But you can prevent this violation.

Prevention:

• when planting seedlings, add to the wells a mixture of onion peel and shredded shells, and later - fertilizing with organic matter containing calcium (crushed eggshell, ash, etc.) or chemistry (calcium nitrate);
• spraying the ovary and unripe berries with 1% calcium nitrate solution;
• creating a healthy microclimate in a greenhouse, with moderate soil moisture, lack of condensation and regular access of fresh air.

Root rot

Fungi that cause root rot - damage to the roots and basal necks, penetrate the plants from the soil and develop quickly with excessive watering. In illiterate agricultural practices, the disease can arise from germination and progress throughout the entire growth of the plant.

With root rot lesions, blackening (browning) and changes in the texture of the roots and their necks (whitish "velvet" coating), as well as their decay and fading, are observed. In sprouts, a flagellum appears under seedbed leaves, and in more adult seedlings, under the first true leaves, the stem easily tears out of the ground, since the root does not develop lateral roots.

If the roots are already infected, then the bush must be removed along with an earthy ball - it is impossible to cure this disease.

Root Rot Warning:

• soil steaming;
• disinfection of the seedling mixture;
• seed dressing before sowing;
• compliance with irrigation regime (only the land is dry);
• fungicide irrigation;
• soil drainage and aeration.

Viral

Of viral lesions that affect tomatoes grown in the greenhouse, it should be noted tobacco mosaic and strick.

Mosaic

When a tobacco mosaic virus is infected, the foliage of vegetables is “painted” into a mosaic of green spots of different shades. Occasionally, yellow spots appear on the fruit. The growth of the bush slows down, the foliage becomes wrinkled and curls. Ripening of vegetables is possible, but they are not tasty.

Unfortunately, antiviral drugs for tomatoes have not yet been developed, so it remains only to snatch the infected shrub from the bed with the root and burn it. And to avoid this trouble, you need to warn her.

Measures to combat viral diseases of tomatoes when they are cultivated in the greenhouse:

• disinfection of seeds, as well as cultivation equipment;
• the destruction of insects, carriers of infection;
• greenhouse disinfection (autumn or spring);
• destruction of plant residues after harvest, deep plowing and steaming of the soil in spring, before planting sprouts.

Tomato Strick

Strick affects the upper parts of the bush, manifesting itself in the form of brown stripes, which eventually dry out. The petioles become weak, and the fruits are riddled with irregularly shaped furrows. With significant lesions the spots merge, and the foliage fades and falls; bushes are oppressed and can also die.

The causes of the disease are the same as in the mosaic: sucking insects, mites and an unclean instrument. It is also impossible to treat strick so far - you can only, or rather, need to remove infected bushes.

Prevention of infection:

• weed removal;
• the destruction of insect pests (insecticide spraying);
• maintaining a stable temperature and humidity, disinfecting seeds before planting, as well as a cultivation tool, annual replacement of the top layer of the earth (with a spade bayonet);
• spraying the seedlings with a solution of boric acid a couple of days before planting, and also watering the soil with a 2% potassium permanganate solution.

Prevention is the best way to avoid diseases of seedlings of tomatoes, and then their treatment will not be required. Only forethought before planting tomatoes and prudent care for them throughout the season will allow them to maintain their health and harvest a rich harvest in the fall.