The most common tomato diseases, description, treatment tips. How are tomatoes sick and how to treat them? Diseases of tomatoes, a description of diseases with photos and methods of treatment - all not to list - this is a brief overview. There are many more diseases. Photos of some (alas, there are many more) that we may encounter at our site will be presented. Therefore, we still do not hurt to get to know them. This knowledge is needed by everyone involved in their cultivation.
Among gardeners, it is believed that the main trouble for tomatoes is late blight. In fact, tomatoes have a lot of diseases in different places or even in the same place, but in different places the plants become infected with different infections. For example, in one section, tomatoes can disappear from late blight, in the second from macrosporiosis, in the third from cladosporiosis. And in order to defeat the disease, or at least for the future, for yourself to know how to preserve your crop, you need to know the main symptoms of the disease.
Many publications often write: tomato - unpretentious culture. Now I would not say that. Too many sores and pests have fallen on this crop in recent years. What does a tomato need? Light, heat, nutrition, moisture. But even if tomatoes are provided with all of this, they are not always successful. Tomato diseases are not rare. Why are they sick? Because the point here is the little things.
Mosaic
Mosaic is a viral disease. The disease is rather unpleasant, because it practically does not respond to treatment. The only remedy is prevention. And then you need to process the seeds before planting. It is useless to treat diseased plants. The leaves of diseased plants acquire a mottled (mosaic) color - dark and light green areas alternate. On the fruits, yellow spotting sometimes develops. If your tomatoes have this disease, then it’s better to simply remove them. Mosaic mainly affects open ground tomatoes. The first source of infection is infected seeds. For prophylaxis, seeds are best etched before planting.
Bacterial wilting of tomatoes (bacteriosis)
Why do tomatoes wilt in open ground or a greenhouse? The external manifestation of the disease - the bush will fade.
This is alarming to gardeners, as symptoms can occur overnight. The lack of moisture in such cases is not the case. Everything happens very fast. With a detailed examination of the dead plant, you can notice the void inside the stem, the presence of fluid inside it. The internal tissue of the stem may turn brown.
It is impossible to cure a disease. All diseased plants urgently need to be removed, destroyed. Experts advise watering neighboring or all (even without signs of disease) plants with a 0.6-1% solution of Fitolavin-300 (watering volume - at least 200 ml for each plant). You can spray the plants with a solution of the same concentration. This will not cure already diseased plants, but will delay the infection of healthy ones (2-3 weeks).
Tomato stem necrosis
Viral disease. The first signs of the disease appear on the stems of well-developed plants when the first hands with fruits begin to form. Small cracks appear at the bottom of the stem, first dark green in color. Then, the beginnings of aerial roots appear in these cracks. The leaves begin to fade, the plant falls, the bush dies. The fruits do not have time to ripen.
Alternariosis or macrosporiosis (brown or dry spotting)
Fungal disease. It affects leaves, stems, less often fruits.
First, the lower leaves become covered with round, large, brown spots with concentric zoning.
In the photo above and below, brown spots on yellowed leaves characteristic of this disease are visible. Very often, beginning gardeners miss this moment, do not pay attention to the yellow leaves, believing that the lower leaves simply die. Perhaps this happens.
But more often they catch it when all the leaves become dry (the second photo below) and only the fruits remain on the plant. You can’t help the bushes at this stage. Therefore, do not wait, try to immediately pick off the leaves starting to turn yellow.
Brown spots increase, merge, the leaves dry out.
On the stem, the spots are oval, dark brown, large with the same zonality.
They cause death or dry rot of the stem.
In fruits, more often in the stalk, dark, slightly depressed spots form. At high humidity, dark velvety sporulation of the fungus appears on top of the spots. The disease on tomatoes is activated at high temperatures, especially at 25-30 ° C.
The fungus is preserved on plant debris and greenhouse floors. Due to abundant sporulation quickly spreads with raindrops, wind.
Alternaria or macrosporiosis of tomatoes, photos and their treatment: for prevention - treatment with antifungal copper-containing drugs. At the first appearance of the symptoms of the disease - treatment with Skor, Ridomil Gold or other antifungal agents. Skor and Ridomil Gold are powerful chemicals - they can be used to treat plants until the ovaries appear, since the waiting period (as long as you can eat the fruits is 50-60 days). If the symptoms of the disease have appeared, and the fruits are already hanging, then it is advisable to treat with biological products, for example, Trichodermin or Immunototsitom, or Immunocytophyte.
Late blight (late blight)
Late blight (late blight) is perhaps the most common disease of tomatoes. They are also sick with open tomatoes. Phytophthora is a fungal disease. And spores of fungi, as we know, develop where there is dampness. Sudden changes in air temperature also contribute to the development of this tomato disease. First blacken, the leaves dry, then the fruits.
But an experienced gardener is able to maximally delay the arrival of this tomato disease in order to have time to collect the maximum number of fruits. I use ordinary plastic bottles with a cut bottom for this. I make holes on the side with a nail, insert the bottle with its neck down near the roots of a tomato bush. That is, I will water the tomatoes not on the surface of the soil, but through the bottle. A bottle of water should be covered on top with something, for example, a mayonnaise bucket. In this case, all moisture will get to the roots, but moisture will not get into the air, the leaves from below will not sweat. That is, with this simple technique we do not create conditions for the propagation of mushrooms in the greenhouse.
You can prevent the development of late blight of tomatoes growing in the open ground or greenhouse by regular (1 time per week) spraying with whey. Lactic acid prevents spores from developing fungi. Also, such drugs as Fitosporin, Barrier, Barrier are also used to prevent late blight.
Chloratic curl of tomato leaves
Affected plants differ in light green or yellowish color, chlorotic appearance, short stature, curly apex. The disease is caused by two viruses - the tobacco mosaic virus and the tobacco necrosis virus. Transmitted with seeds and contaminated soil. The control measures are the same as with the mosaic - disinfection of seeds, soil. Sick plants are best removed.
Chloratic curliness of tomato leaves is often confused with the appearance of torsion of leaves on the tops of bushes (information below).
Cladosporiosis or brown spotting of tomatoes, treatment
Brown olive spotting (cladosporiosis) is also a fungal disease, but it mainly spreads in the greenhouse. First, the lower leaves become sick. Chlorotic yellow rounded spots appear on the upper side of the leaf, which will subsequently merge, look like one single spot. The underside of the leaf is covered with a brown velvety coating - these are spores of the fungus. As a result, the leaves gradually begin to curl and dry. More often, the disease manifests itself during flowering or at the beginning of fruiting. The sooner the infection occurs, the more harmful it is. With high air humidity (up to 95%), daylight hours of about 10-12 hours and low illumination, the disease is more acute.
In the pictures above you will see the manifestation of the disease in the development process - from the moment the first signs appear until the peak of the development of the disease (if you look at the photo from top to bottom).
Fruits are rarely affected by this disease, mainly only if no measures are taken. If this happened, then the fruits become brown-dark, soften - then they still dry out. The cause of the disease can be watering with too cold water, a sharp temperature drop, dampness. Before treatment, all affected leaves break off.
Control measures - copper-containing preparations, for example, Bordeaux mixture or Barrier, Barrier.
Septoria, white leaf spot
Septoria, white leaf spot is a fungal disease. Reduces yield, causing premature drying, falling leaves. At first, single, rounded small bright spots appear. The center of the spot is gray-white, and the edges are slightly darker. Then a black dot appears in the middle of the spot. The disease first affects the leaves, then the petioles, stems. After some time, the leaves become brown, then fall off. High humidity, warm weather contribute to the rapid spread of the disease. The harmfulness of septoria increases in the second half of summer.
Septoria is not transmitted by seeds.
To process with copper-containing preparations, for example, Tsineb, Chorus, copper oxychloride. The earlier the better. It is advisable to remove the affected leaves at the very beginning of the disease, even if only the growth point remains at the tops of the stems.
Gray rot
Gray rot affects the aboveground organs of plants. On the leaves, buds, flowers, brown, wet spots appear, covering in 8-10 hours (usually during the night) the whole plant with abundant ash-gray powder coating - spores of the fungus. On the stems, the spots are brown or gray, first dry, then slightly slime. They are located more often around wound sites, for example, when breaking off stepsons or at branching stems. Spore viability lasts 1-2 years.
Gray rot - it affects tomatoes at the end of summer, when it gets cool, it rains cold. This is one of the common tomato fungal diseases. It occurs with poor ventilation, when the greenhouse is poorly ventilated, with high humidity, a violation of the temperature regime, if we are talking about growing in a greenhouse.
While the fruits are so slightly pronounced whitish concentric spots they are suitable for eating. There will be no particular problems with fruits that manage to turn red on the bush. But problems will begin (if measures are not taken in time) at the end of summer, that is, when it is necessary to collect green fruits for ripening. Then such fruits will spoil first and may infect healthy fruits in the crates. Therefore, if you notice fruits with such whitish concentric circles, it is better to cut off the tops of the bushes so that the fruits have time to ripen on the plant.
One way to deal with this disease is to remove the affected leaves, until the disease has gone further, has not penetrated into the trunk. It is advisable to remove the leaves in sunny weather, so that in the evening the places of pruning of leaves have time to dry out, and the spores of the mushrooms do not get on the trunks. Try not to irrigate irrigation immediately after removing stepsons or leaves.
For the prevention of gray rot, spraying plants with garlic infusion is useful - 30 g of chopped garlic (you can use the arrows) to insist 2 days in 10 liters of water.
Brown rot (phomosis)
Brown rot (phomosis) - develops near the stalk. Outside it may be a small speck, but the core of the tomato will be all rotten. To protect your crop from this disease, fertilizing with fresh manure should also be avoided.
Blackleg
This is a fungal infectious disease. The causative agent of the black leg is rhizoctonia mushroom. Occurs in greenhouses or hotbeds. The spread of the fungus depends on the growing conditions.
Spores of fungi penetrate the root neck of weakened plants. The stem at the root darkens, thins out for 3-5 cm, then rots. And the plants wither, die after 4-6 days from the beginning of sowing.
With sudden changes in temperature, high humidity, thickened crops in permanently used land, lack of ventilation, the disease progresses rapidly.
The main source of infection is contaminated waterlogged soil. With strong waterlogging in the light, microscopic algae begin to grow in the soil on which the fungus grows. The mushroom rhizoctonia, falling into microcracks on the trunks of seedlings, spreads rapidly and the plant dies. The disease also spreads with plant debris, lumps of soil, partly with seeds.
Control measures. Growing seedlings on soil free from infection. With the accumulation of pathogens of the disease - a change of soil or its pre-plant disinfection.
In single cases of infection, it is recommended:
- adding planted plants with sand with a layer of 2 cm, which contributes to the drying of the soil, the formation of additional roots;
- liming of soil in greenhouses or greenhouses;
- loosening the soil;
- systematic ventilation;
- watering the soil with potassium permanganate (3-5 g + 10 l of water).
If a large percentage of the seedlings are infected, then it is usually advised to treat the plants with Previkur or Funadazole. But against the fungus rhizoctonia, these drugs are not effective. Try to find on sale remedies for diseases containing mefenoxam (read the section "composition" in the instructions), for example, Ridomil, Uniform.
It is pointless to spray solutions of these drugs on a sheet, since the main culprit of the disease is in the soil. You will have to shed the soil in which the plants are located. But first you should dry the soil. This can be done often by loosening the soil or pouring sand or peat in pots with seedlings.
Root rot
Root rot - this disease affects both tomatoes and cucumbers. The main reason is poorly prepared soil - a lot of not overripe manure, moist moist soil. To get rid of it sometimes you have to change the whole soil in the greenhouse.
This concludes, perhaps, our review of the diseases that we may encounter when growing tomatoes.
P.S. Those who often go to this page of the site, probably noticed that earlier it was possible to read information about some signs of a lack of various nutrients when growing tomatoes. Yes, it was. But over time, new information appeared, new photos and the page became too voluminous. Sometimes even difficulties with its discovery appeared. Therefore, it was decided to divide the material into two parts. The part that you are reading now is dedicated to tomato diseases. And the other part, devoted to the manifestations of nutrition and care deficiencies on tomatoes, has been moved to a new page. Here is a link to it: What tomatoes lack, how to determine. I advise you not to ignore it, because very often gardeners for diseases take signs that are not diseases.