Late blight appears most often on tomatoes. This disease affects young and adult plants. In order for the cultivation to be problem-free and the harvest to be pleasing with its quality, you need to know preventive measures and methods of control when the disease has already begun to spread.
Signs of infection
Late blight is also called brown rot; it affects vegetable crops, which belong to the nightshade family. It is difficult to fight it, since the fungus cannot be dealt with using simple methods. Therefore, it is better to focus energy on prevention.The spores that cause the disease live in the soil, on the tops of the previous harvest, on garden tools, all year round.
To know how to deal with late blight on tomatoes, you need to find out what caused its development. The likelihood that late blight of tomatoes will appear in the beds depends on certain features:
- the climate that prevails in the region;
- weather conditions at the time of the plant's growing season;
- timing of the appearance of the fungus (the younger the bush, the more destructive the disease is);
- the degree of resistance of the selected variety to diseases;
- carrying out protective measures at various stages: treatment of seeds, soil, seedlings, adult seedlings.
The first symptoms of late blight on tomatoes appear as a white coating on the inside of the leaves. Therefore, the problem is difficult to detect at the first stage. The spores spread quickly and within three days the entire plant is infected. Signs of late blight look like black spots on the leaves, stems, and fruits.
Identifying the cause
Late blight often develops on tomatoes due to improper care. Provoking factors include:
- long rains, foggy weather;
- excessive watering, which does not allow the soil to dry out;
- excessive application of nitrogenous fertilizers;
- lack of microelements in the soil;
- dense plantings, not maintaining distance between planted bushes.
Late blight is also dangerous for greenhouse tomatoes. In a confined space, infection appears more often, since the composition of the soil remains constant. It is necessary to regularly ventilate the room and reduce air humidity if a problem occurs.
How to protect tomatoes, you need to properly care for vegetables. It is necessary to apply fertilizers, loosen the soil and remove weeds on time. You need to water as the soil dries out.If the beds are planted with seeds, then thinning must be carried out at least twice. When transplanting seedlings, you must maintain a distance of 50 cm.
Spores do not like sunny, hot weather. Therefore, during this time their activities cease. But as soon as the rains begin to fall, their distribution reaches a maximum.
How to deal with late blight on tomatoes, you need to consider several points. The plant needs to be watered in the morning so that in the remaining time of the day the moisture is absorbed by the roots and the excess evaporates. You need to pour water at the root, avoiding getting it on the green part of the seedling.
The spread of the disease is observed in the second half of August, when the weather becomes cool and damp. Early varieties of tomatoes, which manage to ripen until the end of August, are most protected from late blight in open ground. They are less susceptible to late blight.
Under unfavorable conditions, spores begin their activity and fall on the greenery along with currents of moist air. How to protect tomatoes from late blight can be done using the mulching procedure. Straw, chopped grass, peat, and sawdust are well suited as mulch.
To prevent black spots from appearing on tomatoes in open ground, they need to be planted at a large distance from each other. In this case, air and light will reach any areas in sufficient quantities.
Preventive actions
To prevent the infection from destroying the crop, it is better to start fighting it in advance. How to cultivate the land as a preventive measure?
- Prevention of late blight of tomatoes begins in the fall, when the harvest is harvested. The tops that remain from vegetable crops must be removed from the garden plot.
- If there is excess lime in the ground, it is recommended to add sand.
- For three years, seedlings cannot be planted in an area where eggplants, potatoes or peppers previously grew.
- Before planting seeds or seedlings, the soil should be watered with a solution of potassium permanganate.
- To prevent diseases, next to tomatoes It is useful to plant garlic and onions.
- Spraying young sprouts with garlic infusion helps. Suitable for preparation are cloves of garlic and tops of the plant, which are crushed and filled with water. Leave to infuse for two days.
- Fitosporin can be purchased at a specialty store. It contains only natural ingredients that do not harm plants. Spraying with a diluted solution is carried out after 1.5 weeks.
If tomatoes are to be grown in a greenhouse, then the entire room, including the ground, must be treated. Prevention of late blight on tomatoes in a greenhouse involves the following measures:
- the top layer is removed by approximately 18 cm, and a new layer of fresh soil is filled in;
- it is useful to plant dill, calendula, mustard, as they fertilize the soil and disinfect it;
- As a treatment for open ground, you can use phytosporin or copper sulfate (the activity of the fungus is suppressed in the treated soil).
The fight against late blight on tomatoes in a greenhouse or in an open area can be carried out using copper wire. Copper contains many trace elements; it is also involved in the synthesis of chlorophyll, respiratory and metabolic processes. With a lack of copper, plant growth stops and immunity decreases. Description and treatment using this method is not complicated.
Copper wire against late blight on tomatoes will increase the plant's resistance to this disease. A regular cable is stripped of its outer sheath and the wire is cut into 4 cm strips.This copper strip is used to pierce the stem of each seedling.
For late blight in a greenhouse, you can use a piece of copper, which is placed under an adult plant. In this case, with each watering, components important for the plant will enter the soil.
Ready-made products from the store
If late blight is detected on tomatoes, how to fight it? You can use purchased anti-phytophthora preparations based on chemical components. Tomato processing can be carried out using such agents as Quadris, Boric acid, Hom, Bordeaux mixture. After treatment with these drugs, fruits cannot be picked for about three weeks.
How to save a plant from late blight, biological preparations come to the rescue. They include beneficial microorganisms that fight pathogenic flora. After them, vegetables can be eaten, but only after washing them thoroughly. Tomato protection can be carried out with the help of Fitosporin, Trichophyte, Guapsin.
Hom does not cope with the large area of late blight, but it perfectly prevents the problem. After treatment, a film is created on the leaves that prevents bacteria from penetrating inside. The active substance is copper oxychloride. 40 g of the drug is dissolved in a bucket of water. You need to spray in calm, dry weather. After spraying, the vegetable crop will be protected for two weeks.
Reviews about these preparations for treating tomatoes in open ground are mostly positive: “I always treat vegetables with Hom at the beginning of summer. I have never encountered late blight before. Now I recommend this remedy to my neighbors in the country, it will definitely protect you from many diseases.”
Therapeutic actions using traditional recipes
If it was not possible to prevent late blight on tomatoes, and black spots were noticed on the leaves, then you need to start fighting as quickly as possible, otherwise the risk of losing the harvest will increase every day.
Treatment of tomato late blight begins with getting rid of infected bushes. It is recommended to uproot the affected plants and remove them away from the garden bed. If the bushes grow in a greenhouse, then after cleaning it needs to be ventilated. The remaining bushes need to be treated with chemical or natural compounds.
Folk remedies for late blight on tomatoes help fight this type of fungus. At home, you can prepare your own medicinal solutions from natural products. To spray tomatoes against late blight, use ingredients that every housewife has in her home.
- Tomatoes can be treated against late blight with table salt, which inhibits the activity of bacteria. You need to dissolve a glass of salt in water. Spraying the green part of the plant is carried out after removing the infected parts. The salt film prevents bacteria from spreading.
- Iodine solutions with whey are popular. Late blight iodine helps disinfect the surface, stop the proliferation of spores and prevent re-infection. A liter of whey is diluted in a bucket of water and mixed with 20 drops of iodine. The components are able to saturate the plant with microelements and prevent the proliferation of bacteria. Spraying once a week is recommended.
- If you decide to fight late blight on tomatoes using folk remedies, then you cannot do without a recipe based on live or dry yeast. Thanks to yeast, not only does the fungus disappear, but also the development of the vegetable improves. You need to water the solution weekly.
- How to get rid of late blight on tomatoes, an infusion based on wood ash helps. The ash is poured with water and infused for three days. Before watering, the solution is diluted with water and crushed soap is added.
Many people advise using wood ash: “Get rid of rot and other infections by sprinkling with a dry protective compound or infusion of wood ash. After it, the plant begins to develop better and does not get sick.”
The fight against late blight on tomatoes using folk remedies is absolutely safe, and the components that are included in the most popular recipes can get rid of the problem for a long time.
You need to know how to fight infection with folk remedies. Be sure to follow the recommended dosages. Many components, if overdosed or improperly prepared, can lead to rotting of the root system.
Other ways to fight
How to treat tomatoes against late blight? Treatment of late blight on tomatoes can be carried out with time-tested fungicides.
- Furacilin against late blight on tomatoes has been used for a long time. The solution has proven itself to be effective. For one liter of water you need to take one tablet. The first time should be sprayed before flowering, then during the formation of ovaries and the last time during the formation of the first fruits.
- Tomatoes are protected from late blight using a composition based on copper sulfate (60 g) or calcium nitrate (30 g). The selected component is poured with water and the bushes are treated before flowering begins.
- How can you fight late blight on tomatoes in a greenhouse? You can treat tomatoes with Trichopolum. The medicine is an antibiotic that can fight many pathogenic bacteria. Take one tablet per liter of water.It is recommended to use the resulting composition every two weeks.
- Metronidazole is used against late blight. It is better to spray the plant in early summer. Two weeks before harvest, the procedure is carried out again. You need to dissolve 15 Metronidazole tablets in a liter of water. Water the soil with the prepared solution; you can lubricate the tomato leaves.
Land after late blight must be treated. To destroy late blight spores, fungicides and biological products are used. Chemicals must be applied in the spring; biological products can be added to the soil at any time except the beginning of flowering. At this time, insects fly to the plants, and the composition of the preparations can be harmful to them.
