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Tomato disease specialists are divided into two large groups - infectious diseases( occurs through the entry of the infectious agent into the body) and non-infectious( caused by abiotic factors).
The causative agents of diseases can be:
Consider how to deal with diseases of the tomato of each group.
Diseases of tomato caused by the bacteria
Bacteria are microscopic unicellular organisms. Live in all environments. Most of them are in soil and water. They penetrate the plant through stomata and mechanical damage, settle inside the tomatoes and multiply, thus infecting them and causing disease.
Found infrequently. The main sign - the defeat of the leaves. First, they are covered with small, oily brown spots of 2-3 mm in size, then they coagulate and die. Fruits and stems are less common.
Pathogen: Pseudomonas syringae.
Infection occurs from accompanying weeds, at low temperature and high humidity bacteria multiply.
Prevention: Disinfection of soil and seeds before planting, climate control in the greenhouse.
Treatment: if the infection has already occurred, the plant is treated with Fitolavin-300 or with preparations containing copper( 1 cup of blue vitriol per bucket of water).Affected leaves are removed. Reduce humidity.
It affects the whole plant: roots, leaves, fruits, seeds. The development of the disease begins with the leaves. With the naked eye you can see brown growths in the petioles - colonies of bacteria. The stem is affected from the inside, becomes empty, yellow. White spots appear on fruits outside. Seeds are deformed, do not grow and do not sprout when planted. The plant becomes contagious to others, the infection can be both on the plant itself, and in the soil, in the seeds. Fruits for food unsuitable.
Pathogen: Clavibacter michiganensis.
Prevention: before planting, soak the seeds in TMTD, spray the culture with fungicides.
Treatment: Sick plants are removed. The protection of healthy bushes is carried out with copper-containing preparations: Bordeaux mixture, Copper sulfate, Copper oxychloride.
Treatment of plants done in dry weather, observing circadian rhythms: 10.00 - 12.00 and 16.00 - 18.00
. The disease develops rapidly: within a few days the plant withers. Although there is enough fluid in the soil, it does not enter the leaves. Stems turn brown from the inside and empty. Treatment of tomatoes from bacterial wilt is not made, the plant will have to be destroyed, and the main thing to be done is to protect the rest of the bushes from infection.
Pathogen: Pseudomonas solanacearum.
Bacteria inhabit the soil and infect the roots of plants, clogging blood vessels. You can see how bacterial mucus is secreted from the affected parts.
Prevention: seed dressing before planting, sterilizing the soil, harvesting last year's plant residues.
Treatment: affected plants are removed, a complex of quarantine measures is taken with Fitolavin-300 solution( at least 200 ml for each plant + spraying)
Rarely encountered, affects the roots. The pathogen is transmitted from other plants through the soil. May get into the plant through fresh slices on the roots, wounds. The incubation period is 10-12 days, then growths appear on the roots, inside which there are colonies of bacteria.
Pathogen: Agrobacterium tumefaciens.
In addition to tomatoes, it affects more than 60 species of plants. Able to live in the soil for several years.
Prevention: sterilization of the soil when planting seeds, processing seedlings in the Fitosporin-M district( 2-3 liters per 1 l of water), preserving the integrity of the root, avoid injury during transplants.
Treatment: the affected plant is removed, the soil of the neighboring bushes is treated with solutions of cartocid or copper oxychloride preparations.
Wet fetal rot
Pathogens are spread by insects and other diseased plants. Favorable factors for development are high humidity and temperatures above 28 degrees. Mostly subject to disease culture, growing in open ground. Those varieties of tomatoes that have a generative gene for growth are resistant to the disease.
The disease affects the fruits, they become soft, darken and rot.
Pathogen: Erwinia carotovora.
Prevention: destruction of insect vectors, soil disinfection before planting
Treatment: the diseased plant is removed, neighboring bushes are treated with FITOLAVIN-300.
The pathogen enters the plant through seeds, soil and other plants. The stems are affected: brown spots first appear on them, then they increase to the size of warts, the stem bursts, the leaves and fruits die.
Pathogen: Pseudomonas corrugata.
Prevention: steaming or calcining the soil before planting, because the pathogen dies at a temperature above 41 degrees.
Treatment: the infected culture is destroyed, the soil is treated with a 0.2% solution of Fitolavin-300.
Black Tomato Bacterial Spotting
Bacteria can kill up to 50% of the crop, affecting all parts of the plant except the roots. Spots appear on tomatoes, which over time increase in size and darken. Bacteria are very resistant to temperature difference, they can develop in cold and heat and remain on the seeds for one and a half years. They die only at temperatures above 56 degrees.
Pathogen: Xanthomonas vesicatoria.
Prevention: seed treatment before planting with Fitolavin-300 or trisodium phosphate, prophylactic seed treatment 1 time in 2 weeks with 1% bordeaux mixture and cartocide.
Treatment: the plant is isolated, the affected areas are removed, the neighboring bushes and soil are treated with fungicides.
Diseases initiated by
viruses Pathogens are viruses that are hundreds of times less bacteria. There are no preparations against viral diseases of tomatoes, therefore the infected plant is subject to isolation and destruction. The carriers are both parts of infected plants and insect pests. Much attention should be paid to prevention, which includes a whole range of measures to combat tomato diseases:
- soil treatment before planting: disinfection, calcination;
- seed preparation, pre-disinfection;
- isolation of diseased plants;
- compliance with the rules of landing: the distance between the bushes, water and light mode;
- compatibility with other crops, do not plant tomatoes near plants - potential carriers of viruses, remove weeds;
- pest control.
Another name is seedlessness. The virus infects the generative parts of the plant. The flowers grow together, deform, the seeds do not ripen in the fruit. In the photo of tomatoes suffering from aspermia, it can be seen that the leaves of the plant become small, the stem is weak, and the peduncles do not develop.
Pathogen: Tomato aspermy cucumovirus.
Aspermia virus enters tomatoes from insects or other plants( for example, from chrysanthemums)
Preventive measures include:
- isolation and destruction of diseased plants in greenhouses;
- fighting aphids;
- weed control;
- divide geographically tomatoes and chrysanthemums.
A sign of infection with a leaf bronze virus - the appearance of a characteristic pattern on fruits and leaves in the form of brownish rings. The main carriers are thrips. The virus dies at temperatures above 45 degrees.
Pathogen: Tomato spotted wilt virus.
Prevention: roasting the soil before planting seeds, destroying thrips.
The curly virus in tomatoes infects leaves that become small, deformed, unevenly colored. The bush does not grow in height, the fruits are not tied.
Causative agent: Tomato yellow leaf curl virus.
Prevention: Whitefly most often becomes the carrier of the virus. Therefore, preventive measures are aimed at preventing the reproduction of these insects.
Bushiness Manifestation of the disease is first noticed on the leaves. White dots appear on them, which then darken. Leaf blades become coarse, streaks turn blue, the leaf itself curls at a sharp angle. The bush takes the form of a spindle.
Pathogen: Tomato bunchy top viroid.
Prevention: Aphid, infected seeds become the carrier of the virus. The virus is deactivated at a temperature of 75 degrees. Preventive measures consist in tillage before planting and destruction of aphid colonies.
Infection occurs from affected seeds. Most often occurs in plants grown in open ground. The leaves are covered with light and dark spots, like mosaics, on the fruits - yellow spots.
Pathogen: Tomato mosaic tobamovirus.
- Seed treatment before planting.
- The diseased plant is removed.
- Fallen bushes are burned.
- From folk remedies, it is proposed to process young bushes 3 times a month with urea milk.
Infection occurs on leaves, stems, flowers and fruits. The leaves change color, first turn pink, then darken, become coarse and brittle. The edges are wrapped and the sheet looks like a boat. Flowers grow together, lengthen, petals remain small. Usually the fruits of them are not formed, or small tomatoes appear, with uneven color, white and solid from the inside. You can not eat them.
Most often the virus infects southern cultures, its main carriers are cicadas.
Pathogen: Lycopersicum virus 5 Smith.
Prevention: disinfection of planting material and soil, isolation of tomatoes from other vegetable crops, control of insect vectors.
Fungal diseases of tomatoes
The fungus can infect any part of the plant. This is the most common group of diseases.
Fungi causing rotting are called rot. It can be of different types: brown tomato rot, black, white, gray, root, apical. Common is the nature of the lesions and the prevention measures. Consider several types of rot.
The fungus enters the plant through the soil. Fruits are covered with weeping white putrid spots.
Most often damaged areas are affected - in the ruptures of the skin of the fetus with excessive growth, mechanical damage, as well as violations of transportation and storage conditions.
Pathogen: a fungus of the genus Sclerotinia.
Prevention: disinfection of soil during planting, compliance with the rules of transportation and storage.
Treatment: Treatment of plants with a solution of copper sulphate, urea and zinc, diluted in water.
Can destroy 50% of the crop. Mycelium of the fungus penetrates into the stem and fruits, tissue necrosis develops, they soften and become covered with gray bloom. Spores of fungi are very viable, persist in the soil for several years. Can spread from other cultures( for example, cucumbers).The infection spreads through the air and through the water.
Pathogen: a fungus of the genus Botrytis cinerea.
- reduction of air humidity in the greenhouse;
- removal of infected plants;
- to prevent small wounds and cuts through which infection may occur;
- periodic greenhouse disinfection.
Treatment: chemicals( Bayleton, Euparen), treatment with sodium HUMAT.An effective means is to coat the lesions with a fungicidal paste mixed with CMC glue. This procedure should be repeated 1 time in 2 weeks so that new stains do not appear.
Tomatoes root rot
Another name is black leg. Due to the appearance of the affected area: the upper part of the root at the root of the neck blackens and rots. The whole plant dies next. The fungus spreads in moist soil and remains on plant residues and seeds. Primary contamination comes from old soil and peat. Excess moisture exacerbates the disease.
Pathogens: fungi of the genus Rhizoctonia solani.
Prevention: observe irrigation, seed and soil disinfection before planting, for example, Pseudo-bacterin-2 at a rate of 1: 100 l of water, sulfur-containing preparations are also effective
1 year tomatoes in this place is not planted.
The next group of fungi infect leaves with different spots. Hence their name is spotting. There are black, gray, white, brown, yellow spot on the leaves of tomatoes.
Another name is white spot. The fungus infects the leaves, they are covered with light spots, deformed and dry. The most favorable conditions for the fungus - the temperature of 15 to 27 degrees and humidity from 77%.The fungus is preserved on residues from the plant.
Pathogen: the fungus Septoria lycopersici.
Prevention: removal of plant residues, respecting the distance when planting, isolate tomatoes from other nightshade.
Treatment: Spraying with fungicides.
The second name is brown spot. It affects the leaves, which appear orange-brown spots that darken over time and become covered with bloom. Like all mushrooms, the causative agent of the disease of tomato develops at high humidity and temperature. Disputes persist until 10 years. Breeders are constantly improving the varieties of tomatoes, bringing resistant to kladosporiozu species.
Pathogens: fungi of the genus Passalora fulva and Cladosporium fulvum.
Prevention: the use of varieties that are immune to the disease.
Treatment: spraying with drugs: XOM, Abiga-Peak, Poliram.
Another name is the gray leaf spot of a tomato. The etiology of the disease is still the same. Spots of gray-brown are formed on the affected leaves. They increase in size, are interconnected, affecting the leaf tissue. The plant fades.
Pathogens: fungi of the genus Stemphylium solani.
Prevention: sanitation of soil and seeds before planting, compliance with the light regime.
Treatment: Spraying with fungicides.
Fungus infects the leaves, stems and fruits of tomatoes. First, the disease progresses on the leaves, they are covered with large dark brown spots and dry up gradually. It also darkens and dies the stem. On fruits, spots are formed at the stem, with enough moisture, spores of the fungus develop. The top of the tomato becomes dark, depressed, with a velvet bloom. Especially fast the fungus grows at a temperature of 25-30 degrees and high humidity.
Pathogen: mold fungus Alternaria solani Sorauer.
Prevention: seed and soil treatment with antifungal agents( Trichodermin, Fitosporin, etc.), choose varieties of tomatoes that are resistant to the disease.
Treatment: treatment with copper-containing drugs( Ridomil Gold, Skor) during the vegetative period, if the fruits have appeared - biological products.
It is impossible to plant tomatoes in a place where potatoes, eggplants, cabbage, and pepper grew before.
Anthracnose tomatoes become ill with adult plants. The fungus can infect leaves and fruits. In the first case, the leaves wither, the stem becomes bare, the roots are deformed, they become weak and thin, the plant breaks loose easily. On the affected parts you can see small black seals consisting of the mycelium of the fungus.
If the fungus struck the fruit, they are covered with flattened flat spots.
Pathogen: fungi of the genus Colletotrichum.
Prevention: seed treatment with Agat-25, in the vegetative period, Quadris or Strobe, or on the basis of a hay stick.
Treatment: During the development of the disease, gardeners recommend spraying the bushes with the drug Poliram with a consumption rate of 2.53 kg / ha.
Fungal disease affecting the old leaves of tomatoes. Chlorophyll production is impaired, so the leaves fade and die. Mycelium of the fungus is resistant to temperature fluctuations and long stored in the soil and on plant residues. Later, the roots and stems are infected. The disease spreads from the bottom up to 1 m in height. There are no drugs that completely conquer the fungal spores. When choosing varieties of tomatoes should pay attention to the resistance to verticillus.
Pathogen: fungi of the genus Verticillium.
Prevention: the use of varieties that are immune to the disease.
Treatment: the diseased plant is eliminated, fresh soil is laid out in its place, and the soil is regenerated using crops such as rye, peas, mustard. They contribute to the development of microorganisms that destroy harmful fungi.
Able to infect huge areas. Microscopic spores of the fungus look like white bloom on the leaves of tomatoes. The affected plant is deformed. Parts of the leaf become discolored, the plant weakens and dies. Most often develops in closed ground.
Pathogen: marsupials of the genus Oidium erysiphoides Fr.
Prevention: the use of varieties that are immune to the disease, the implementation of measures to disinfect greenhouses.
Treatment: spraying with fungicides, sodium humate 0.1 and 0.01% completely destroys the fungus, Topaz, Kvadris, and Strobe also are effective.
The second name is stem cancer, because the fungus first infects the plant stems, and then the disease spreads to the leaves and fruits. The affected areas darken, weeping indented spots appear on them. Promotes the development of the fungus cold and wet weather. Spores of the fungus are long preserved in the soil, on plant residues and seeds. Most often affects greenhouse plants, in the open field is rare.
Pathogen: mushrooms of the genus Ascochyta lycopersici.
Prevention: treating the soil and seeds before planting, raising the temperature with a decrease in humidity, airing greenhouses.
Treatment: treatment of spots with a special chalk paste, spraying with growth regulators( Agat-25, Immunocytophyte)
A rather common disease among the nightshade. There are varieties of tomatoes resistant to the fungus Fusarium, when planting should pay attention to it. If there is no such mark, then it is worth carrying out preventive measures to avoid infection.
The disease manifests itself in the leaves and develops from the bottom up. Chlorous spots appear first, then the leaf is deformed and the shoots wither. If you put a sprig of an infected plant in a glass of water, you can see white mycelian filaments of fungi in 1-2 days.
The fungus is particularly harmful to greenhouse crops, affecting the vascular system of plants. Infection occurs from plant debris.
Pathogen: fungi of the genus Fusarium oxysporum.
Prevention: Tillage before planting with Pseudobacterin -2, petrolmidazole, crop rotation, microbiological recultivation.
Treatment: Trichodermin, Benazole, Planriz are effective anti-fungal drugs.
A common disease of tomatoes in open ground. Mycelium of the fungus through the soil affects the root system and stem. The leaves are covered with red spots, on the back side you can see a bloom of light gray. Fruits form solid brown spots, they rot and fall. Infection can occur from other solanaceous( for example, potatoes).
Pathogen: fungi of the genus Phytophthora infestans.
Prevention: soil sterilization before planting, treatment with Pseudobacterin -2, during the vegetative period - with HUMAT sodium.
Treatment: removal of infected plant parts, spraying plants with a 0.5-1% Baktofit solution with an interval of 8 days or with Agat-25.
Diseases of tomatoes caused by abiotic factors
These include genetic disorders, adverse weather conditions, improper care.
Vertex rot of fruits
It develops in large fruits due to unfavorable soil or genetic disorders with a lack of calcium ions. Fruits are covered with brown spots on the top, which sometimes occupy a third of the tomato.
Prevention: the use of calcium fertilizers, compliance with watering.
When the disease does not form seeds. Occurs with violations of pollination processes and the lack of nutrients( especially potassium)
Prevention: compliance with recommendations for the cultivation of tomato crops, irrigation regime, selection of soil, fertilizing.
Cracking of fruits
Cracks on the tomatoes appear when there is an excess of moisture in the soil. This happens after heavy rain or watering, especially in crops with large fruits and thin skin. For the health of the whole plant, this phenomenon is not dangerous. Fruits remain edible, but it is desirable to remove them from the bush immediately, as they noticed cracking, since spores of rot may settle on the wound.
Large varieties usually burst along the radius, while small varieties, such as cherry, circle. Prevention consists in observance of the mode of watering and timely collecting large fruits.
Scarring( deformed tomato)
Occurs in large-fruited varieties. This phenomenon is a consequence of the merging of flowers. The reason is the predominance of nitrogen in the soil and lack of phosphorus. The bush grows, the flowers do not separate. They are called "terry".The result is a giant fruit of irregular shape with scars - "clasps".Prevention - to remove already formed double flowers, to monitor the mineral composition of the soil.
Yellow tomato disorder
With a lack of organic matter in the soil, high acidity and low phosphorus content, the disease of uneven fruit ripening “yellow disorder” can develop. Such tomatoes never ripen to the end, remaining half yellow. Inside, they are light, solid and tasteless. Exit - to establish mineral metabolism in the plant nutrition.
Tomatoes do not like direct sunlight and high temperature. Leaves and fruits can get sunburn. Plot in these places is discolored. Spores of rot can penetrate the wounds of the fetus, so it is better to remove it from the bush. For prophylaxis, choose shady tomato areas with well-drained soil or install light filters.
Manifested in the form of small bumps on the leaves of a tomato. This phenomenon occurs due to improper irrigation, violation of turgor and water-salt metabolism. It is necessary to rearrange the plant to a more spacious place, ventilate and process copper-containing drugs.
Blue color of foliage and stem
Sometimes after transplanting seedlings, gardeners observe a change in the color of the plant: the stem of a tomato turns blue, and the leaves turn a shade of purple. Most often this is due to a sharp change in temperature. If there are no other signs( fading, staining, etc.), then there is nothing to worry about - the color will be restored as soon as the temperature is above 15 degrees.
For a plant to be stress-resistant to climatic extremes, it must be hardened!
External changes may indicate a lack of trace elements for plants. The table below shows the signs by which you can analyze the sufficiency of inorganic elements in the nutrition of tomatoes.
Breeders and agronomists offer all new methods to combat tomato diseases. In the gardener's arsenal there are biological products, chemicals, new varieties of tomatoes that are resistant to fungal diseases. The complex of agrotechnical measures, compliance with the rules of planting, timely prevention will help preserve the harvest.