How to fight late blight on tomatoes. Late blight, or brown rot of fruits. Late blight on potatoes - treatment

Late blight – common fungal disease, which mainly affects plants from the Solanaceae family. Tomatoes suffer the most from it. The disease is insidious and so total that within one or two weeks it can destroy a tomato crop that you have carefully grown and almost brought to ripening. How to fight late blight on tomatoes? There are several solutions.

To choose best practices struggle, it is necessary to find out how this disease occurs, what its nature is, and what this fungus of the same name is “afraid of.”

Late blight affects almost all varieties of tomatoes, except those to which breeders have grafted increased stability to this disease. But even sowing resistant varieties is not a 100% guarantee that your tomatoes will be protected from late blight damage. Therefore, it is of great importance preventive measures.

The disease has the following “clinical picture”:

Blackening of tomato fruits does not always occur due to late blight. Sometimes this is a reaction to other problems or unfavorable growing conditions (poor soil, dryness, excess moisture, pest damage). But in most cases, this sign indicates late blight.

Late blight produces a fungus, Latin name which is Phytophthora infestans. The phrase has a rather harsh translation - “destroying a plant.” The disease fully corresponds to its name; if the causative fungus gets on a tomato bush or other plant, it is quite difficult to save the plant.

Causes

What conditions must be met for the late blight fungus to enter the plant and begin to multiply there?

Not enough air

It is well known that for good care Plants need moisture, but many people forget that air is no less necessary. Late blight thrives in environments where there is not enough air penetration. For this reason, it is necessary to plant tomatoes of all types, and it is especially recommended this procedure for tall tomatoes.

Protected ground

Protective shelter can provoke the occurrence of disease. At night and during the day, the temperature in the greenhouse differs sharply. Due to these fluctuations, condensation collects on the film surface from the inside, which forms increased humidity. Phytophthora fungus spores require a moist environment to more easily penetrate the plant.

High humidity

Long rains and high humidity air when growing tomatoes in open ground.

During the rainy season, the likelihood of late blight infection increases, especially if the optimal temperature regime(for tomatoes it is +19°С…22°С).

Cool nights are a plus high humidity will almost certainly result in the tomatoes becoming infected with fungal spores.

Along with tomatoes, potatoes, peppers, and eggplants are actively infected with late blight. When planning plantings, you should not grow these plants side by side, and you should, if possible, observe crop rotation or thoroughly disinfect the soil after harvesting.

How does infection occur?

Late blight is transmitted by everyone different ways: through infected stems, leaves, fruits and tubers; downwind and through the soil. The fungal spores are washed off with water when watering and are spread on the soles when moving around the area.

The fungus can live in the soil for several years, especially in soil that contains small amounts of copper compounds.

How to prevent late blight from tomatoes

Potatoes are the first to be affected by late blight. If you grow this crop, try to protect your tomatoes from infection. This can be done by disinfecting potato leaves and tops. Leaves that show signs of damage, mainly those located in the lower tier, should be removed from the bush. Additional hilling also helps, as a result of which the formed potato tubers located further from the soil surface.

You can protect tomatoes by limiting the spread of fungal spores on them. You should not plant these two crops in close proximity, and if this cannot be avoided, you can create “living barriers” between them by sowing with thickened planting climbing beans or green peas.

When growing tomatoes in greenhouses, care should be taken to ensure that not only humidity and temperature are controlled, but ventilation is also provided.

Before planting tomato seedlings, you must do the following:

1. Prepare appropriate place. Avoid proximity to other nightshades, especially potatoes.
2. Clear the soil of debris, all last year's organic waste, grass and anything else that may harbor the late blight virus.
3. Provide ventilation (in the greenhouse), or select an area that is blown by the wind, but does not have a constant draft.

After planting the seedlings, during their growth period, before the fruits begin to form:

How to get rid of late blight

Even before the formation of the ovary, without waiting for signs of the disease to appear, it is better to spray the tomato bushes with 1% Bordeaux mixture.

As soon as you notice that the pigmentation of the foliage or stems has changed, and even more so if the fruits that have set begin to turn black, remove infected plants and diseased plants immediately and burn them.

Potato and tomato tops, in order to avoid the proliferation of fungal spores throughout the area, is not laid in compost pit, even if the plants are visually healthy.

Disinfecting treatment

There are many folk and agrotechnical methods treatments that will help prevent the onset of late blight, or protect plants if the disease has already occurred.

Any processing should be carried out in dry, windless weather. The rainier and colder the summer turned out to be, the large quantity treatments may be necessary.

In addition to mineral and organic fertilizers, it is necessary to feed tomatoes with biosubstances that will strengthen their immunity.

Folk remedies

Garlic

Infusion of garlic with potassium permanganate. It is prepared as follows. For 100 g of garlic heads, stems or young leaves, take a glass of water. Grind the garlic in any way, leave in water for 24 hours. Strain thoroughly and dip into a 0.1% solution of potassium permanganate, volume 10 liters (for this volume of water, to obtain a 0.1% solution you will need 1 g of potassium permanganate powder).

Spray the ovary for the first time, then 10 days later. After this, three more sprayings can be carried out at intervals of 12-14 days.

Serum

Ideally, it will be whole cow's milk and not powdered milk. It must be fermented to separate the whey. Dilute it with water in a 1:1 ratio. Spraying should begin at the beginning of July. This remedy is rather preventive, so the irrigation procedure can be carried out daily or every other day.

Iodine milk

To prepare this disinfectant you will need low-fat cow's milk. For 10 liters of water, take one liter. 20 drops of 3% iodine tincture are also added there. With the beginning of the formation of the ovary, iodine-milk irrigation can be carried out every two weeks.

Ash

Ash is used not for spraying, but for dusting. You can start a week after planting the seedlings. After watering, spray the sifted ash thickly onto the bushes and soil, including between the rows. When the fruits begin to set, repeat the procedure, but this time only dust the soil between the rows.

Yeast solution

Dissolve a 100-gram pack of raw baker's yeast in 10 liters of water. If the first signs of late blight are noticed, begin regular weekly spraying of yeast solution on the leaves and stems, especially in the lower tier.

Saline solution

10 liters of water consumes 200 g table salt. It must be well dissolved. Processing is carried out on fruits that have already begun to form, but are not yet large. The salt film will protect the tomatoes from fungal attack, but spraying must be carried out in such a way that it is not immediately washed away by rain or when watering. Before spraying, carefully remove already affected fruits or leaves.

Agrotechnical methods

Copper sulfate

The inorganic compound copper sulfate is a real “lifesaver” for the gardener, helping in the fight against many diseases and pests. Late blight is no exception. To rid tomatoes of it, you need to treat them before flowering. aqueous solution of this substance, in the proportion of 2 tbsp. powder per 10 liters of water.

The period of action of the drug is 30 days, so one high-quality treatment will be enough.

Calcium nitrate

Has a powerful protective effect. For 10 liters of water, calcium nitrate will require one tablespoon. It not only helps in the fight against late blight, but is also a nitrogen fertilizer that increases plant immunity. Tomatoes are sprayed once before flowering.

Fungicides

One of the most popular representatives of this class of biological substances is Fitosporin-M. They are starting to use it for protection at the seedling stage. Seedlings are dipped in a solution prepared according to the instructions before planting.

Then the plants are sprayed every 10 days until fruit sets. Can be watered with solution upper layer soil.

Other biological drugs:

• Alirin-B
• Gamair
• Oksikhom
• Ordan
• Ridomil Gold.

If folk remedies can be used almost throughout the growing season, the use of fungicides is limited to the time of fruit set and formation. And although efficiency chemical substances above, better take care of early processing harmless means.

Late blight poses a serious threat to tomatoes. This crop is not characterized by problematic cultivation, but this disease can be considered the most common and difficult to cure. In order for tomatoes to ripen healthy, gaining full consumer ripeness, varietal taste and weight, concern for the eradication of late blight on the site should be a priority in their care.

There is probably no person on earth who does not like tomatoes. We eat them both fresh and canned, use them in salads, tomato pastes, ketchup, all kinds of seasonings, etc. Some people buy vegetables in a store or market, while others prefer to grow them on their own personal plots and in greenhouses. So, gardeners often encounter various diseases of tomatoes, including late blight.

Late blight on tomatoes: description

Late blight is a fungal disease that affects almost all crops of the nightshade family (tomatoes, potatoes, etc.). The disease is caused by a specific fungus - late blight, which has more than 100 species.

What is late blight and how does it manifest itself?

Late blight or late blight on tomatoes is a brown rot that affects the fruits and leaves of plants of the nightshade family (potatoes, tomatoes, eggplants, peppers). The disease is caused by fungal spores that all year round live in the soil, on old vegetable tops, the surface of greenhouses, garden tools, etc. The danger of the disease lies in the fact that cool and damp weather, as well as night fogs, contribute to the rapid spread of late blight. Infected fruits quickly rot and fall off, which often leads to complete loss of the crop.

The duration of the incubation period from the moment the fungus enters until the first appearance signs disease is determined external factors and ranges from three to fourteen days.

Dark brown or black spots irregular shape first appear on the foliage, and then gradually move to the stem and fruits. In damp weather, with high air humidity, a whitish oily coating forms on the spots, which indicates the spread of the fungus.

The clusters begin to turn yellow and black, after which they wither and fall off before they have time to form fruit. Appear on the bottom of tomatoes spots dark- Brown, which gradually increase in size. On initial stage As the disease progresses, the hardness of the tomato remains, but as the fungus grows, the fruit softens.

Late blight affects not only the outer part of the plant, but also its intercellular cavity, which leads to oppression of the bush and its further death.

Favorable conditions for the development of the disease

Since fungal spores do not tolerate sun rays and are inactive under their influence in hot, dry weather, the risk of late blight affecting tomatoes is minimized. But when air humidity rises, which happens during fogs and rains, the fungus activated and begins its negative impact.

If the rainy weather lasts for more than two days, your tomatoes are likely already infected with late blight. Do not get carried away with excessive watering of tomatoes, because by doing so you create favorable conditions for the development of late blight. Plants should be watered in the morning so that the moisture has time to be absorbed during the day and only under the root; under no circumstances wet the foliage.

The risk of late blight is especially increases at the end of August, since during this period the nights already become cool, and as you know, dampness and cold are the most important factors, promoting the development of late blight.

When growing tomatoes, temperature conditions play an important role, which is easiest to maintain in a greenhouse. But here too there are certain rules: greenhouses or greenhouses should be regularly ventilated to avoid the accumulation of condensation, otherwise the air humidity will increase greatly.

In addition, there are the following causes late blight development:

• Shortage useful microelements- iodine, potassium, manganese, copper in the soil;
• excess nitrogen fertilizers;
• dense plantings, that is, insufficient distance between bushes and much more.

In order to prevent the development of late blight, preventive measures are taken.

How does late blight become infected?

The disease spreads quite quickly and the appearance of at least one infected plant can lead to damage to other tomato bushes. Sources of transmission of fungal spores are following:

Late blight on tomatoes: how to fight?

It is quite difficult to fight this disease. There are many methods for combating late blight on tomatoes, and each gardener can choose the most effective method, in his opinion. Experts recommend alternating folk remedies and medications, since monotony can be addictive and, as a result, lead to a decrease in the effectiveness of protective agents.

Before you start processing plants, it is necessary to take into account some nuances regarding the treatment procedures:

Preparations for combating late blight on tomatoes

To date, there are no drugs whose action is aimed specifically at combating late blight, therefore Special attention is given to preventive agents with a fungicidal effect, providing comprehensive protection from many diseases.

Fungicides are divided into the following kinds:

• Protective(contact). Such drugs are used for preventive purposes. Their action extends only to the treated surface of seeds, stems, leaves and fruits, as a result of which fungal spores are destroyed and their reproduction is stopped. The effectiveness of the preparations is determined by the amount of the product, the duration of exposure, the degree of preservation in the treated areas, weather conditions and chemical resistance.
• System. The method is based on the ability of the active substance to penetrate inside the plant, gradually spreading throughout its entire vascular system, thus acting directly on the infectious agent and inhibiting it.

Chemicals protect the plant both outside and inside, and in the early stages of the disease they can save tomatoes from late blight.

The effectiveness of such agents depends on the speed of penetration active substance in plant tissue, while weather play almost no role. Just a few hours after treatment, a protective barrier is established and exposure to moisture does not in any way affect the effectiveness of systemic medications. Their effect lasts for several weeks.

Have proven themselves well chemical products containing live bacteria and copper. Their effect is to suppress pathogenic microorganisms at the initial stages of the disease, that is, even before the spores penetrate into the plant. It is recommended to spray the bushes in dry weather before lunch.

Use chemicals to protect plants from late blight should only be done as a last resort, after others have more safe ways did not give results.

Scheme for treating tomatoes against late blight

You need to know that plants can be treated before and after planting, as well as during flowering and formation fruits

Folk remedies for combating late blight on tomatoes

There are many folk ways combating tomato diseases such as late blight. Before deciding to use a specific facilities, you need to try each of them and make a choice based on the test results. After all, susceptibility to active ingredients at different varieties tomatoes vary. In addition, the effectiveness of the drug often depends on weather factors.

Late blight is an insidious disease, which can be overcome with a creative approach, as well as a desire to experiment. After all, it happens that a product that worked well last season is no longer next year may not be as effective.

You can quite successfully fight late blight on tomatoes if you strictly follow the proportions for preparing infusions and solutions, as well as the timing of treatment.

Boron, iodine and dairy products

Iodine has a powerful antimicrobial effect and serves as an excellent treatment for late blight on tomatoes. There are many folk recipes using iodine, some of them are indicated below.

• Mix water (10 l) and whey (1 l), add hydrogen peroxide (1 tbsp) and iodine tincture in alcohol (40 drops).
• Take water (8 l) and mix it with whey (2 l), add iodine tincture (15 drops) and sugar (0.5 tbsp.).
• Mix water (9 l) and low-fat milk (1 l), add iodine (20 drops).

Using one of the prepared solutions, carefully treat the stems and foliage of tomatoes, especially on the back side. Also, for preventive purposes, you can use solutions of whey and fermented kefir (1 l/10 l of water). The product is used in pure form or with added sugar. This solution must be watered weekly, immediately after buds form.

The element boron has also proven itself quite well. To prepare the mixture you need to take boric acid(10 g) and dilute it in hot water(10 l), let cool to room temperature and spray tomato bushes. For greater effectiveness, it is recommended to add iodine (30 drops) to the solution.

And finally, a remedy that has shown excellent results in the fight against already noticeable manifestations of late blight, which is prepared according to the following recipe:

Components:

Stir the ash in hot water, cool the solution to +20 degrees, then add boric acid and iodine. Leave the mixture for 12 hours, then dilute with water in a ratio of 1:10. Spray all parts of the plant with the resulting solution. Before carrying out the procedure, all damaged areas of the bush should be removed.

Ash solution

Ash is considered a fairly effective folk remedy in the fight against late blight on tomatoes. This is explained by what it contains great amount all kinds of microelements, each of which is capable of providing favorable impact on tomato bushes. To prepare the mixture, you need to mix ash (5 l) and water (10 l), leave for three days, stirring occasionally. Then add water to the solution until the volume reaches 30 liters and a little soap to ensure better adhesion to the foliage. The mixture is ready to use.

Such treatment of plants is carried out at least three times per season: 10-12 days after planting seedlings in the ground, at the beginning of tomato flowering and immediately after the formation of the first ovaries.

In order to prevent late blight, as well as when the first signs of the disease appear, you can use a yeast solution, which is prepared as follows: stir fresh yeast (100 g) in water (10 l). Water or spray the plants with the resulting solution.

Garlic tincture

Fungal spores do not tolerate garlic, so treatment garlic tincture can be quite effective. To prepare the product, you need to take crushed heads and shoots of garlic (1.5 tbsp), mix with water (10 l), and leave for 24 hours. After that, strain the solution and add manganese (2 g). Regularly spray the tomato bushes with the resulting product every 12-14 days, starting from the moment the ovaries form. About half a liter of infusion is consumed for each plant.

Copper

It's pretty interesting way fight against late blight, which consists of supplying tomatoes with copper microparticles in order to repel the fungus. To do this, take a thin copper wire and cut it into small pieces, no more than four centimeters long. Each piece should be peeled or calcined and pierced into the lower part of the plant trunk. The ends can be bent downwards, but under no circumstances should they be wrapped around the stem.

This procedure is carried out only after the tomato stem is sufficiently strong.

Late blight of tomatoes requires annual treatment, even though you managed to get good harvest. If, nevertheless, the remedy you have chosen does not bring desired results and some of the fruits had to be destroyed, no need to be upset. It’s just that next year you need to use other means that will be more effective.

We will tell you about pepper diseases and methods of combating pepper diseases.

If all the rules of agricultural technology are followed, peppers usually do not get sick. Of all vegetable peppers reacts most strongly to monoculture (growing a crop year after year in the same place) - the susceptibility of plants to pathogens increases. Therefore, peppers should not be placed after peppers and other plants of the nightshade family (eggplant, tomato, potato). The proximity of peppers to cucumbers is also unfavorable, as they can be carriers of the cucumber mosaic virus, a disease that is also dangerous for peppers.

Late blight, or brown rot of fruits

Late blight is one of the most common and harmful diseases of pepper and other nightshade crops. Late varieties or plants are especially affected late dates planting, since favorable conditions for the development of the disease occur in the second half of summer and autumn, when the temperature during the day is still quite high and the nights are cold.

Late blight affects leaves, stems and fruits. Large brown spots appear on the leaves, located mainly along the edges leaf blade. A white cobwebby coating of sporulation of the pathogen forms on the underside. Diseased leaves dry out quickly.

Brown, elongated spots without plaque appear on the petioles of leaves and stems. On fruits, the disease manifests itself in the form of rot, the development of which can occur both during the growing season and during storage of fruits. On the surface and inside, the fetal tissue turns brown, remaining hard. A coating of sporulation on fruits forms only with prolonged moisture (drizzle, fog, sweating of fruits with a sharp change in day and night temperatures).

The source of infection of nightshades with late blight is mainly potato plantings affected by this fungus. Further spread of the infection occurs through spores of the pathogen formed on the leaves.

Measures to combat late blight: spatial isolation of potato plantings from other nightshade crops; use of higher doses potash fertilizers, increasing plant resistance to late blight; spraying plants from the moment the first signs of late blight appear and again 2-4 times with an interval of 7-10 days with copper-containing preparations.

White rot, or sclerotinia

This disease usually develops in the root part of plants. The affected part of the stem is covered with white mycelium of the fungus. Black solid formations appear inside the stem (sclerotia - compacted dehydrated mycelium of the fungus). Infected fruits become soft, watery, and in some places covered with a white flaky coating. Usually, white rot manifests itself in patches and causes attacks on a small number of plants. The infection persists in the form of sclerotia on affected plant debris and in the soil.

Measures to combat white rot: maintenance moderate humidity soil after planting seedlings. Periodically remove all dying leaves, shoots and plants. Dust the affected areas with crushed coal or chalk. Watering with warm water.

Gray rot

The disease mainly develops in film greenhouses, where optimal mode temperature and humidity. At high humidity (80%) and low temperature (+10-15°C), all above-ground parts of plants are affected. Symptoms appear in the form of brown, weeping spots, which are covered with an abundant grayish coating of sporulation of the fungus. First of all, the lower parts of the stems in contact with the soil are damaged. The main sources of infection are mycelium and spores on affected plant debris, which are spread by air currents, drops of water, and lumps of contaminated soil.

Measures to combat gray mold: crop rotation, compliance with the rules of agricultural technology, timely and thorough destruction of dying and affected parts of plants.

Black bacterial spot

This is a bacterial disease that occurs on peppers in open and protected ground. The pathogen affects leaves, fruits, and stems from the time of emergence. Small black spots with a yellow border first appear on the leaf blades, then increasing to 1 - 2 mm. The spots on the stems and leaf petioles are also black, but elongated. The affected fruits are initially covered with dark, raised dots with a watery border. Subsequently, the spots on the fruits increase to 6-8 mm and form ulcers. Plants affected by at a young age, often die. The disease deteriorates the quality of fruits and reduces yield. The development of the disease is promoted by high humidity and air temperature +25-30°C. Bacteria penetrate into leaves through stomata, and into fruits through mechanical damage, and persist (up to 10 years) in plant debris and seeds.

Control measures: It is necessary to observe an annual fruit rotation, collect and destroy plant debris, select healthy fruits to obtain seeds. Carry out pre-sowing disinfection of seeds. In case of severe damage to plants in greenhouses, the soil is disinfected or replaced.

Fruit blossom end rot

The disease often occurs on pepper fruits. Symptoms of the disease are determined by 2 types of damage: non-infectious and infectious (bacterial) origin.

With the first type of disease, a watery liquid appears at the top of the fetus. green spot, which gives way to a dry brown concentric spot around the apex. Such fruits ripen earlier and then rot. Plants are more affected when there is a lack of moisture in the soil and high temperature air (more than +30°C), as well as when growing them on acidic and saline soils.

With the second, bacterial, type of disease, gray spots with a dark border appear on the fruits. The fruits quickly soften and rot. The source of infection is seeds and plant debris.

Protective measures: exact compliance agricultural cultivation techniques .

Non-infectious diseases of pepper

Non-infectious diseases can be caused by poor eating habits of peppers. With a lack of nitrogen (especially in the period from germination to fruit formation), plants become pale green in color, their growth slows down, which leads to the formation of fewer flowers and fruits. The leaves become hard, erect, gradually turn yellow from the main vein to the edges and fall off. The fruits are set, but the plant discards some of them. Excess nitrogen causes strong growth of stems and leaves. Plants “fatten”, but at the same time they set little fruit and are less resistant to pathogens.

A characteristic sign of phosphorus deficiency- lilac color of leaves and their wrinkling. This color appears first on the lower leaves, then on the leaves of the middle tier, and gradually the stems acquire a brick-lilac hue. Phosphorus deficiency is most often noticeable in seedlings when they are grown on soils mixed with peat. If you do not feed the seedlings in time, the stem becomes thinner, the leaves curl along the main vein, root system develops poorly. Excess phosphorus (extremely rare) prevents plants from absorbing iron and zinc from the soil.

For potassium deficiency You may notice the appearance of a rapidly yellowing border or spots (marginal burn) along the edges of the lower and middle leaves. Leaf tissues near the veins remain green for a long time. The main stem and shoots become woody. The leaves, starting from the lower ones, turn brown, dry out, and droop. Ripe fruits have a heterogeneous color. With an excess of potassium, the leaves become dark green color, growth is slower, plants absorb zinc, manganese, and boron worse.

If you don't have enough calcium, the leaves in the upper part of the plant turn yellow, while the lower ones remain green, the roots are underdeveloped. Subsequently, the color and shape of the leaves change: grayish-yellow mottling and awl-like appearance appear. At long-term deficiency calcium, the growing point of the plant dies. Excess calcium is also undesirable: it prevents the entry of boron, iron, nitrogen and potassium into the plant.

Magnesium deficiency noticeable on older leaves where chlorosis appears. The entire leaf turns yellow, starting from the edges, and becomes covered with | brown spots. Leaves fall off quite quickly, flowers and fruits are damaged. Excess magnesium occurs when there is an imbalance between calcium and magnesium. In this case, the roots of the plants suffer.

Boron deficiency always manifests itself on young plant organs. The leaves remain small, become deformed over time, and their edges curl downward. The growing points die off, the growth of shoots and root tips stops. With a lack of boron, flowers are poorly fertilized and fall off. Often plants suffer not from a lack of boron, but from the inability to absorb it due to prolonged drought, an alkaline reaction of the environment, and improper application of calcium. Excess boron in natural conditions usually not observed.

Late blight is one of the most common diseases that affects. Very often, gardeners encounter this disease when growing potatoes and tomatoes. Let's figure out what kind of disease this is, how to fight it and save the harvest.

The fungal disease late blight is also called potato or brown rot.. The disease is dangerous because it progresses very quickly and a short time may spread to the entire crop.
Development cycle of late blight First of all, it is the fungus that gets sick, and after 10-15 days the fungus also affects the tomatoes. It appears in the form of spots on the above-ground parts of plants, fruits and tubers.

Epidemic outbreaks of this disease are directly related to bad weather conditions: rainy summer with significant differences in day and night temperatures - best time for fungal activity.

This fungal disease can occur in different ways, depending on the pathogen that provoked it, as well as climatic conditions.

The main signs of the presence of late blight are considered to be the following:

1. Brown or brown spots with a white edge appear on the foliage of plants.
2. From below sheet plate covered with a whitish cobwebby coating.
3. Yellowing, curling, drying out and subsequent death of foliage.
4. Stems and petioles are covered brown spots, which grow with lightning speed and affect the entire tops of the plant.
5. Rotting of stems.
6. Darkening and then shedding of flowers and ovaries.
7. On tomato fruits it appears in the form of spots, which subsequently provoke softening and rotting of the tomatoes.
8. Potato tubers are covered with dense spots.

Tomatoes affected by photoblight

Important! Incubation period late blight varies from 7 to 10 days.

The development of late blight is facilitated by several factors, primarily unfavorable weather conditions, namely sudden temperature changes and excessive humidity.

Prolonged fog, heavy dew and rain often cause plant infection.
Signs of late blight in potatoes Poor quality planting material or infected material can also become a source of this disease.

Another reason for the occurrence of late blight is improper agricultural technology, in particular, too dense plantings and the presence of .

Important! When choosing planting material Preference should be given to varieties that are resistant to late blight.

It is quite difficult to overcome this disease. Great importance has timely diagnosis, since if the disease is neglected, the crop may not be saved.

There are several ways to treat and prevent fungus, let’s look at which ones.

Drugs

Fungicides are suitable for combating late blight; these preparations contain copper, which is effective against the fungus:

• . 20 days after the emergence of seedlings, the plants are treated with a 0.02% solution of the drug. The procedure is repeated during the flowering period;
• . Potatoes and tomatoes are treated with a 1% solution of this substance 20 days after the sprouts appear, and then during flowering;
• . Used to treat late blight plants before flowering at the rate of 25 g of the drug per 100 sq. m. m;
• "Revus". Before the first buds appear, the crops are treated at the rate of 6 ml per 100 square meters. m;
• . Potent, it is used when there is a threat of late blight epidemic. In such cases, plantings are treated at the rate of 20 ml of the drug per 100 square meters. m.

Important! Treatment of tomatoes with fungicides, provided that it is necessary to preserve the crop, is carried out no later than 21 days before the fruit ripens.

Experienced gardeners claim that there are quite a lot safe methods combat this disease, the use of which is allowed at all stages of the growing season and allows you to save plants and crops. Let's look at the most effective ones:

In order to minimize the likelihood of late blight, the soil should be properly prepared before planting tomatoes and potatoes.

To do this, in the spring it is necessary to clear the area of ​​young and last year's growth and loosen it well.
After this, the soil must be disinfected; this can be done using chemicals or folk remedies.

Any copper-containing preparations are suitable for soil disinfection; treatment should be carried out 2-3 weeks before the intended planting. Experienced gardeners also use a weak solution of potassium permanganate for this purpose.

Treatment and prevention

Unfortunately, 100% protection against late blight does not exist, but carrying out preventive measures before and after planting significantly reduces the likelihood of its occurrence.

To prevent the disease, chemical and biological drugs. It is important to understand that chemicals cannot be used during all periods of the growing season, since potent substances can penetrate into the fruit and thereby make the crop hazardous to health.

Did you know? One of the causes of the famine in Ireland in 1845-1849, when more than a quarter of the island's population died, is considered to be late blight, which destroyed almost the entire potato crop, which at that time was the staple food of the Irish.

As for biological products, they can be used at almost any stage of plant development without fear of harmful effects on the fruits and the environment.

On tomatoes

To prevent the occurrence of late blight on tomatoes, the following measures must be taken:

1. Choose only high-quality, healthy material for planting.
2. Disinfect seeds before sowing in a 1% solution of potassium permanganate for 20-30 minutes.
3. Plant tomatoes away from potatoes.
4. Keep a distance between bushes; dense plantings contribute to the occurrence and development of the disease.
5. Do not oversaturate the soil with nitrogen.
6. Provide good drainage to prevent fluid stagnation.
7. Plant in sunny areas.
8. Follow the recommendations of experts regarding crop rotation.
9. To plant .

Video: prevention of late blight on tomatoes

Before planting in open ground, seedlings must be sprayed with copper sulfate or Bordeaux mixture. After 14 days, the bushes are sprayed again in the garden bed.

Any chemical preparations for the treatment of tomatoes are allowed to be used at least 3 weeks before the expected ripening of the fruit.

Therefore, experienced vegetable growers often use folk remedies rather than fungicides to treat late blight of tomatoes.

On potatoes

To prevent late blight on potatoes, you must adhere to the following recommendations:

1. Take only healthy tubers for planting; to check for the presence of fungus, it is recommended to keep them in a warm room with a temperature of 15-18 °C for 10-15 days before planting. If the potato is infected, it will develop rotten spots.
2. Do not plant nightshade crops in the neighborhood.
3. Avoid dense plantings.
4. Give preference to varieties resistant to late blight.
5. Carry out preventive spraying with fungicides or biological products every 2 weeks from the very beginning of the growing season.
6. Follow the rules of agricultural technology, namely loosening the soil and weeding from weeds.
7. Regularly apply phosphorus-potassium fertilizers.

Video: how to protect potatoes from late blight

This fungus is classified as incurable diseases, therefore, all the gardener’s actions should be aimed at preventing the development and spread of late blight. To do this, treat with fungicides according to the instructions for use.

Late blight affects not only potatoes and tomatoes, but also other nightshades. Peppers and eggplants often suffer from it. To treat these crops, fungicides are used, just like tomatoes, they are sprayed with solutions of such chemicals.

When growing vegetables in a greenhouse, cucumbers can also suffer from the disease, so it is extremely important to control the moisture level in the room and prevent the development of the disease. Cucumbers can only be treated folk remedies aimed at combating late blight.
Late blight on cucumbers

Did you know? Although many people claim that tomatoes and potatoes affected by this disease should not be eaten, in fact, no studies have been conducted on the consumption of such fruits. There are only assumptions that this should not be done, even for aesthetic reasons, because the stains that cover such vegetables do not look at all appetizing. But whether to eat them or not, everyone decides for themselves.

Late blight is a common dangerous fungal disease. Most the best option to combat it is to try to prevent its appearance in your garden, and to do this you should follow the rules of agricultural technology that are indicated for nightshade crops.

Late blight. How to fight?

The best protection against late blight is prevention

Not all gardeners suffer from late blight, or late blight, as this scourge is often called. In principle, if you follow all the rules of agricultural technology, then late blight is not so difficult to avoid, especially in greenhouses. But the trouble is that this disease primarily affects potatoes - the pathogen appears faster where the humidity is higher. Once late blight appears on potatoes, expect it on tomatoes in a week, especially side by side, in open ground or in a tunnel. On small areas Where it is difficult to maintain crop rotation, late blight poses a particular danger.

The first symptoms of the disease appear where moisture is retained the longest - on the lower leaves along the edges of the blade. They appear as dark brown spots that quickly enlarge, especially in warm and humid weather, becoming almost black. On the underside of the leaves, at the border between the affected and healthy tissues, a white coating appears, clearly visible in the morning, when dew is still present. White plaque- this is the sporulation of a fungus, and the appearance of this plaque indicates danger. This means that measures urgently need to be taken, but more on them later.

In 3-4 days, late blight can destroy the entire area if dry and hot weather(it stops the development of the disease). But even if the humidity is not very high, some bushes are very quickly affected by late blight from an excess of nitrates and a lack of copper, boron, manganese - these microelements protect against late blight.

Tomatoes, as you know, require dry air. If you notice that moisture accumulates on the walls of the greenhouse in the morning, immediately arrange ventilation (preferably through). By the way, when coming to the greenhouse with tomatoes after visiting a potato field, be sure to change your shoes and clothes if the first signs of late blight appear on the potatoes.

Greenhouse tomatoes Late blight is not dangerous if you follow all the rules of agricultural technology. Firstly, it is dry air, which means watering in the first half of the day (only at the root) and mulching the soil. Underground watering helps a lot - for example, using plastic bottles. To avoid stagnation of moisture (and not only for this purpose), remove all lower leaves, stepsons.

Counter attack

As soon as the first two or three leaves affected by late blight have appeared, you should inspect all the bushes daily (or better yet, several times a day) and, of course, take protective measures.

It is better to send the children to the potato field at this time - let them play hide and seek, scouts or catch up (with the condition that they can only move between the bushes). In the morning they will shake the tops, and the rest of the time they will check for late blight. This ingenious way prevention of late blight was known to our grandparents.

When they did without inorganic chemicals, the fruits grew environmentally friendly. However, even today many, including your humble servant, use only natural remedies, safe for health. Here are some of the recipes for combating late blight - accessible, inexpensive, without side effects.

When there is a threat of late blight, tomato fruits can be treated with infusion of onions, garlic, radish roots, poplar leaves or bird cherry. The most affordable and effective remedy- infusion of garlic bulbs and tops, since by this time the garlic is already ripening. For a bucket of water you will need a head of garlic or a mixture of small cloves with stems (150-200 grams). The raw materials are crushed, filled with water and infused for several hours. If only stems are used, then the solution must be infused for a day.

After filtering, the resulting product is sprayed onto the plants, adding soap for better adhesion. If there are not many tomatoes, then it is advisable to wipe each fruit with a cloth soaked in the solution (personally, I don’t use soap for sticking; a light garlic solution holds well anyway). Rubbing tomatoes with a garlic solution helps even when the first signs of late blight appear on the bushes.

If the air in the greenhouse is not dry enough, and the time for the development of late blight has begun, then for prevention, the fruits can be sprayed with solutions containing dairy products or, in extreme cases, pollinated with chalk. For a bucket of water - 0.5 liters of milk plus 20 drops of iodine. You can spray the plants back - 1 sq. I will need a glass of skim milk.

By the way, both peppers and eggplants can be affected in the same way as tomatoes and potatoes, so preventive measures for all nightshades are the same. For example, it is very useful to water plants with nettle infusion. If this is done constantly (once every 7-10 days), then the leaves remain clean until the end of the growing season, and immunity to fungal diseases is developed.

Tomatoes are known to require copper. Of the simplest and available ways can be called piercing the stems with a thin copper wire bent in the shape of the letter G. If you have old copper coins or plates, then they can also be stuck into the soil next to the bush.

Many people use ash infusion for prevention (especially for potatoes). It is useful to spray all nightshades with a 10% solution of table salt when there is a threat of late blight - as a result, protective film, preventing the development of both late blight and other fungal diseases.

The development of late blight is also inhibited by mushroom infusion, oddly enough. The infusion serves as a kind of “antidote” both against late blight and powdery mildew. Once you have cleaned the mushrooms, do not throw away the waste. Fill them with water, having first crushed them, and after 1-2 days of fermentation, dilute with water (10 times more water), strain - and spray the plants.

It is better to use not one method, but different ones, alternating them and combining them with fertilizing, watering, that is, following the recommendations Lunar calendar. We spray it once with kefir - the plant receives calcium, the second time with a light pink solution of potassium permanganate, etc.

All measures used to prevent late blight are suitable for combating other diseases. Just like late blight, it can be prevented gray rot, brown spot, vascular bacteriosis and fight them in much the same way.

I would like to remind you that you need to care for plants at a favorable time and not provoke the appearance of diseases, creating good conditions for pests and dangerous diseases.