In the greenhouse and open field, tomato bush often cause disease. Some of them carry pests, while others attack plants due to non-compliance with the rules of agricultural engineering or the effects of adverse weather.
Any of these causes can have dire consequences for your harvest. Therefore, it is important to identify the disease in time and begin treatment. Of course, in the field it is not so easy to do this, because many pathogens disguise themselves perfectly. But we hope that detailed descriptions and photos will help you navigate.
Below we consider the most common signs of fungal, viral, bacterial and some other diseases that can attack your beds. And also present the measures to combat them.
Using chemicals, remember that tomatoes can be eaten only 3-4 weeks after the last treatment.
Brown spots on the leaves, stems and fruits of tomatoes
Necrosis of brown color with light edging is formed on the leaves and stalks. On the reverse side of the sheet plates in wet weather there is a whitish bloom. The plant dries out. Fruits from the inside are coveredbrown spots and rot.
Diagnosis: phytophthora (phytophtorosis) of tomatoes - a fungal disease caused by microscopic fungi Phytophthora infestans.
The disease is activated in wet weather, especially dangerous in the second half of summer, when nighttime temperatures become much lower than daily readings. Also on the development of the disease is influenced by fog and dew. At risk - tomatoes in open field and film greenhouses without heating. After damage to the leaves and stems of the phytophthora, it passes to the fruits and makes them unfit for consumption. If the signs appeared at the beginning of the growing season, a complete loss of the crop is possible. The disease spreads very quickly, especially in wet weather.
Phytophthora also affects potatoes, eggplants, sweet peppers and other Solanaceae.
Control measures. To prevent phytophthora, spray Abiga-Pik, Concent, Revus or other fungicidal plants. Repeat the treatment every 10 days. If the bushes are severely affected, use Kuproksat or Infinito fungicides. Just before maturation - biological products Fitosporin and Gamar. If the fruit began to turn black, remove the surviving unripe tomatoes and lower for a minute in hot water (50 ° C). Then dry and put in the box for ripening.
- Effective folk remedies from phytophtora on tomatoes and potatoesThe fight against blight is not easy. How to protect tomatoes and potatoes from this disease?
Small spots on the leaves, dark depressed spots on the fruits of tomatoes
On the leaves and stems visible spots up to 1.5 cm in length, sometimes with black bloom. Lesions are most often formed along the edges of the sheet. Then the spots grow and merge. The stalks crack, and the fruits are ulcerated with dark, dry spots.
Diagnosis: Alternaria, or dry spotting, of tomatoes is a fungal disease.
Alternariosis attacks plants immediately after transplanting tomatoes into open ground or a greenhouse. The fungus loves dry and hot weather, so it is especially dangerous for plants in glass greenhouses and film greenhouses. All parts of the bush are affected, and in the absence of treatment, the yield loss is up to 85%. Fruits from infected bushes are not subject to storage. The disease is easily transmitted to the potato, and vice versa, so it is better not to plant it next to the tomatoes.
Control measures. Spray the affected bushes with a 0.4-0.5% solution of Acrobat or Ordan preparations. The fungicides Ridomil Gold, Poliram, Cumulus, and Sectin Phenomenon also proved to be well proven in the fight against Alternaria. Process according to the instructions every 7-10 days until the signs of the disease disappear.
Round brown spots with dark edging on the leaves of tomatoes
On old, and then on young leaves, small watery spots appear. At first they are not very noticeable, but then turn white and covered with a brown edging. The rest of the leaf turns yellow and dries out. The fruits are small and sluggish. Young leaves at the top of the bush are rarely affected.
Diagnosis: Septoria, or white spot, of tomatoes is a fungal disease.
Most often, the disease affects plants in the open field. Foci of septoria can also occur in the greenhouse at high humidity. The fungus moves from the lower leaves and stem base to higher, damaging young leaves, shoots and flowers. As a result, the bush is forced to spend energy on the restoration of green mass, and not on the setting of fruits and their ripening. The spores of the fungus spread rapidly throughout the garden. High humidity, heat, windy weather contribute to the reproduction and dispersion of the pathogen.
Control measures. At the initial stage of infection, it is important to remove the affected leaves so that the spores do not scatter with the wind on other plants. If the bush is completely affected by septoria, it is better to dig up the plant and burn it. Fungicides Acrobat, Ridomil Gold, Ordan, Fundazol, etc. are suitable for processing tomatoes. Spraying of copper sulphate (50-100 g per 10 l of water) is also effective.
Yellowish spots on the leaves of tomatoes
First, the lower leaves are stained, then the disease spreads to the whole plant. The leaves dry out, curl and fall off, on the fruits there are hard spots of olive color.
Diagnosis: cladosporia, or brown spot, of tomatoes is a fungal disease.
The development of the disease is promoted by growing in unheated and rarely ventilated greenhouses. Most often leaves are affected. Fruits, stems and ovaries suffer less frequently. But since plants lose their foliage, the harvest is very poor. And if the disease goes to the fruits, then they shrivel and shrink.
Control measures. Treat the first lesions with Abiga-Pik or Poliram. During the summer, spray the bushes with 0.05% Fitosporin solution. For prevention, regularly remove old leaves and maintain moisture in the greenhouse not higher than 80%.
White bloom on the leaves of tomatoes
Leaves on both sides are covered with white bloom. Rounded spots are located all over the leaf plate, then merge and darken.
Diagnosis: powdery mildew of tomatoes is a fungal disease.
The development of the disease contributes to excess nitrogen fertilizer and errors in watering. Tomatoes of open ground powdery mildew does not cause much damage, but the greenhouse falls hard. The processes of photosynthesis are disturbed, the leaves gradually die off. In severe lesions, the stems and flower stalks turn white. The fungus weakens the immune system of plants and significantly reduces the yield. If you do not take action, the bush can completely die. Many summer residents take white bloom for dust, but in fact it is the mycelium of the fungus, which grows very quickly and is transferred to other plants. He can also cover the fruit, degrading their taste.
Control measures. When the first signs appear, treat the tomatoes with the fungicides Quadris, Topaz, Cumulus, Prevent, etc. For prevention, spray the beds with 0.5% Baktofit solution. After two weeks, repeat the procedure. The third treatment spend through 7-10 after the second.
Dark indented spots on the fruits of tomatoes
Fruits are covered with softened spots up to 1 cm in diameter. At first, they are hardly noticeable and do not differ from the skin color. Then darken and turn black. Fruits are fully mummified. Brown scaly spots are visible on roots.
Diagnosis: Tomato anthracnosis is a fungal disease.
Anthracnose is widely found both in open field and in greenhouses. More often adult bushes suffer from it. The peak of the disease occurs at the end of summer and the beginning of autumn. Mainly affected fruit, roots and root neck. Ripened tomatoes can not be eaten, they are watery and tasteless. The spots darken with time, and spores of the fungus become visible on them. Often, anthracnose appears on the bushes along with Alternaria, causing a mixed infection.
Control measures. Remove affected fruit and spray bushes with copper chloroxide (40 g per bucket of water) or 1% Bordeaux liquid. The latter can be used for the prevention of disease. To do this, spray the planting 3-4 times every 10-12 days. When the greenhouse becomes empty, conduct its complete disinfection using bleach (200 g per 10 liters of water).
Necrotic spots on the leaves and stems, white spots on the fruits of tomatoes
The stems and petioles become covered with ulcers, the stems crack, slime stands out from them. Leaves dry and curl on one side, but do not fall off. Fruits are speckled with fine hard specks. The plant fades.
Diagnosis: Tomato bacterial cancer is a disease caused by non-spongy aerobic bacteria.
Greenhouse tomatoes, which grow in conditions of high humidity and low light, suffer from cancer most often. Also, heat and waterlogging affect the development of the disease. Crop losses can reach 30%.
Control measures. Affected plants do not respond to treatment. Dig them up and burn them. Process the remaining tomatoes with 1% Bordeaux liquid to prevent infection.
Tomato leaves are twisted, yellowish in color, white bloom on roots
The lower leaves die off quickly, the stalks are deformed. Tops of bushes become lethargic. The vessels in the stems turn brown, the metabolism is disturbed and the plant fades.
Diagnosis: Fusarium wilting of tomatoes is a fungal disease.
The disease is very dangerous, because Fusarium causing fungus is resistant to many chemicals. At the same time difficult to diagnose. Many people confuse the disease with non-infectious chlorosis, arising from improper irrigation and the introduction of top-dressings, or verticillis, which is also characterized by wilting. Meanwhile, it is the pronounced chlorosis in this case that excludes the disease of verticillus and, together with the above symptoms, speaks of the infectious origin of the disease.
Control measures. Treat affected plants with Fundazole, Benazole or Strekar. These preparations can also be used for seed dressing before sowing. For prophylaxis after planting, pour tomatoes with Pseudobacterin.
The lower leaves of tomatoes dry and fall, the upper leaves curl
Leaves partially turn yellow, then necrotic spots appear on them, the roots gradually die off.
Diagnosis: Verticillary wilting, or Verticilliasis, of tomatoes is a fungal disease.
More recently, verticillosis was one of the most dangerous and common diseases of tomatoes. But as of today, many varieties and hybrids resistant to it have been bred; therefore, infection occurs less frequently. Meanwhile, the wilting fungus still lives in the soil and under favorable conditions (low temperature and high humidity) infects plants. Particularly affected are young bushes of tomatoes, which just started to grow.
Control measures. For treatment, use drugs Previkur, Trichodermin, Topsin-M. After picking, when the plants take root, feed them with this mixture: 2 g of copper sulfate and zinc, 3 g of boric acid and 10 g of potassium permanganate per bucket of water. After 10 days, repeat the procedure. Spend the third dressing after 20 days, and after another 30 days - the fourth. This will strengthen the immune system of tomatoes.
Watery spots on the leaves, stems and fruits of tomatoes
The lesions increase in size, then the sporulation of the fungus in the form of brown spots becomes noticeable on them. The leaves turn yellow due to metabolic disorders. The plant fades and dies.
Diagnosis: Tomato rot is a fungal disease.
The fungus is activated during fruiting in wet weather. The first signs of damage can be seen on the leaves. Small gray dots quickly become large, merge and covered with bloom. The disease is especially dangerous for greenhouse tomatoes, which grow in conditions of high humidity.
Control measures. If there are few lesions, immediately treat the plantings with this composition: in 1 liter of water add 1 cup of ash and 1 tsp. copper sulfate. The mixture is enough for 2-3 sq.m. With a strong manifestation of the disease, spray the leaves and stems of tomatoes with Fitosporin or 1% solution of Bordeaux liquids.
Light speckled spots and shriveled areas on tomato leaves
The leaves are speckled in color, then deformed and acquire a filamentous shape. Leaflike outgrowths appear at the bottom. The plant slows down in growth, cannot take fruit and soon dies.
Diagnosis: Tomato mosaic - a viral disease.
Mosaic causes enormous damage to tomatoes in the open field and greenhouse. Plants pick up the virus during the invasion of aphids, nematodes and thrips that carry the disease, as well as tissue damage by dirty garden tools. If a shrub is infected at the beginning of its development, its fruits will grow defective and unfit for food. Possible loss of half the crop.
Control measures. Infected plants cannot be treated. To stop the spread of infection, scoop them up and burn them. Cultivate the land with Ridomil Gold, Kuproksat or other fungicides. Weakly affected bushes can be sprayed with a solution of whey (100 ml per 1 l of water) with the addition of Pharmaiodus. For prophylaxis before sowing, dress the seeds in a 1% solution of potassium permanganate.
Watery dark spots on the bottom of the fruits of tomatoes
First, at the base of the fruit (often green or just beginning to ripen) appear subtle watery specks, which soon increase in size and become brown. A third of the fruits turn dark, shrivel and turn black.
Diagnosis: Tomato's apical rot is a physiological disease associated with violations of agricultural engineering and plant genetic characteristics.
The disease usually occurs due to improper watering or excessive foliar plants. Also, unbalanced feeding and developmental features of fruits cause rot, when nutrients (in particular, calcium) do not have time to get to the top. This is especially true for large-fruited varieties of tomatoes. Temperature drops can influence the appearance of watery spots. Tomatoes are affected in greenhouses and open ground. The bushes weakened by a disease badly fructify. Rotting fruits damage the immunity of plants. As a result, up to 50-60% of the expected yield may disappear.
Control measures. At the first signs, remove the rotted fruit from the bushes and spray the leaves with a 0.2% solution of calcium chloride. Repeat the treatment two more times during the week. For prevention, treat the leaves and soil with a solution of calcium nitrate (1 tbsp per 10 liters of water). Do not apply too much nitrogen fertilizer, exclude the introduction of fresh manure. During autumn digging, enrich the soil with calcium.
White and yellow stripes on the fruits of tomatoes, leaves and stems purple hue
The fruits are lignified and tasteless, inside are covered with a white network of vessels. The leaves are stranded, have an unnatural color, eventually shrink. Stamens and pistils in flowers are underdeveloped. The roots are covered with cracks. The plant is stunted.
Diagnosis: Mycoplasmosis, or stolbur, of tomatoes is an infectious disease caused by mycoplasmas, the smallest bacteria that live in the vessels of plants.
Stolbur often affects plants in open ground. The peak of the disease usually occurs at the end of August. The disease is carried by sucking insects, in particular, the cicadas (slobbering pennitsa), a dangerous pest of a vegetable garden. The risk of infection with stolbur increases in hot and dry weather when insects actively reproduce. Also, the infection can get into the soil through infected seeds and seedlings.
Control measures. Infected bushes need to dig, because they cannot be treated. To prevent re-infection need to deal with weeds. As well as spray planting from the cicadas using Kinmiks or Tsvetofos. It will also help dusting the plants with wood ash (30 g per bush).
Tomato Disease Prevention
Preventive measures will help you protect plants from pathogens:
- plant disease-resistant tomato varieties;
- before sowing seeds on seedlings, dress them with Fitolavin, Fundazole, Strekar or TMTD;
- disinfect garden tools;
- decontaminate the soil with the help of Trichodermine, Fitosporin and other chemical preparations; a solution of potassium permanganate is also suitable;
- reject weak and diseased plants;
- observe crop rotation;
- increase plant immunity with a double dose of potash fertilizers;
- observe the mode of watering and feeding;
- adjust the temperature and humidity in the greenhouse (the norm is not higher than 32 ° C and 80%);
- kill pests and weed;
- wash the greenhouse at the end of the season, remove crop residues and dig the soil.
To increase the yield of tomatoes every year, monitor the health of the plants and take timely measures to combat major diseases. Also read about how to identify and cure diseases of cucumbers, peppers and zucchini.