Phytophthora (lat. Phytophthora)- a genus of fungus-like protists that causes late blight disease, most often affecting nightshade crops, including tomatoes. Phytophthora has more than one hundred species. The name of the disease “late blight” consists of two ancient Greek words and translated roughly means “destroying or destroying a plant.” Indeed, this disease can destroy a plant in just a few days.

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Late blight (late blight) of tomatoes - description

Phytophthora is tenacious and ubiquitous: it lives on seeds, plant debris, soil, greenhouse walls, and garden tools. The disease progresses in cold and wet weather. Most of all, late blight loves calcareous soils, thickened plantings into which fresh air is difficult to enter, temperature changes, dew, and plants weakened by poor or insufficient care.

Signs of late blight on tomatoes

This common and most dangerous disease can be diagnosed based on several signs:

• the underside of the leaf blade becomes covered with spots, gradually the leaves turn brown, dry out and fall off;
• the shoots of the plant darken and then turn black;
• Black areas form on the fruits.

We will try to give you as much information as possible about this disease and answer your questions:

• late blight on tomatoes - what to do?
• How to protect tomatoes from late blight?
• how to fight late blight (late blight) on tomatoes?
• How to treat tomatoes against late blight in open ground?
• how to get rid of late blight on tomatoes?

Treatment of tomatoes against late blight

How to treat tomatoes against late blight

There are many chemical means of destroying late blight, but they have the same principle of action. In a long fight against late blight, it is best to alternate means of protection, since late blight is very tenacious and easily adapts to the drug if you use it from year to year.

Remedies for late blight on tomatoes

How to treat tomatoes against late blight? Tomatoes are treated for late blight with fungicides. In amateur gardens and vegetable gardens, the most commonly used drugs for late blight are Previkur, Fundazol, Fitosporin, Quadris, Ridomil, Switch, Skor, Topaz, Horus, Fundazim, Tiovit Jet, HOM, Bordeaux mixture, copper sulfate, copper oxychloride, Trichopolum and other. But sometimes the fight against late blight on tomatoes is carried out using old, centuries-tested folk remedies.

In the photo: Phytophthora on a tomato stem

How to treat tomatoes against late blight

How to spray tomatoes against late blight? Dissolve 2 tablespoons of copper sulfate in 10 liters of water and treat the tomatoes with this mixture before flowering. You can also use calcium nitrate as a fungicide - dilute 1 tablespoon of the substance in 10 liters of water.

The antibiotic Trichopolum is also used to protect against late blight, dissolving 10 tablets in 10 liters of water and treating tomatoes with this composition twice a month. And fungicides from the store (Fitosporin, Fundazol, etc.) are diluted in accordance with the manufacturer’s instructions. The first treatment of tomatoes is carried out at the stage of ovary formation, after which spraying is repeated every ten days.

If tomatoes are severely affected by late blight, it is necessary to remove and burn all the affected leaves, and treat the fruits, and especially the stalk, with a one percent solution of calcium chloride.

Watering tomatoes against late blight

You can maintain the level of protection of tomatoes from fungal infection by adding a fungicide to the water for irrigation every now and then. The dosage of the fungicide is determined based on the recommendations of the drug manufacturer.

In the photo: Tomatoes affected by late blight

Spraying tomatoes against late blight

Treating tomatoes against late blight with chemicals gives a quick and reliable result, but it is undesirable to use them on already ripening fruits, as this may negatively affect the quality of the crop. How to be?

How to deal with late blight so that it does not affect the quality of tomatoes? You can protect tomatoes from disease using preventive measures or non-toxic folk remedies. But if you decide to use fungicides, treat the tomatoes with them before flowering, before the first ovary appears, then again after two weeks to consolidate the result. In the future, the use of the fungicide should be stopped and only folk remedies to combat late blight should be used.

Folk remedies for late blight on tomatoes

How to fight late blight on tomatoes with folk remedies

Late blight on tomatoes at the very beginning of the disease can be destroyed using less radical methods such as treating the garden with fungicidal preparations. Folk remedies for treating tomatoes against late blight may not be so effective, but they are harmless to the human body. How to save tomatoes from late blight using folk remedies?

Garlic-manganese infusion against late blight on tomatoes

You can treat them with an infusion of garlic with potassium permanganate - 100 g of garlic minced in a meat grinder (you can use not only the cloves, but also the leaves and arrows of the plant for this purpose), pour a glass of water, leave for a day, strain and, diluting this infusion in 10 liters of water, add 1 g of potassium permanganate to it.

In the photo: Tomato bush with late blight

Infusion of straw against late blight on tomatoes

Pour a kilogram of rotten hay or straw into 10 liters of water, add a handful of urea and let it brew for 3-4 days. Strain the infusion and treat the tomatoes with it.

Late blight yeast on tomatoes

Dissolve 80 g of yeast in a bucket of water and pour this solution over the tomatoes at the first symptoms of late blight.

Copper wire against late blight on tomatoes

Spraying tomatoes against late blight can be replaced by “copper piercing.” How to protect tomatoes from late blight using copper wire? The wire needs to be calcined over a fire or sanded, cut into pieces 3-4 cm long, insert such a piece into the stem of an adult tomato bush at a height of 10 cm from the soil and bend the ends of the wire down. Never wrap the wire around the stem!

Some gardeners prefer to wrap pieces of copper wire around the roots of the seedlings before planting them in the garden. The fact is that microdoses of copper, enhancing oxidative processes, stabilizing the production of chlorophyll and stimulating oxygen metabolism, strengthen the plant’s immunity and make it resistant not only to late blight, but also to other infections.

Iodine for late blight on tomatoes

Everyone knows about the antimicrobial effect of iodine, so the method of spraying tomatoes with a milk-iodine composition is widely popular among gardeners. For 10 liters of water, one liter of low-fat milk and 20 drops of iodine are enough.

In the photo: What stem blight looks like

Ash solution against late blight on tomatoes

This treatment is carried out in three stages: as soon as the seedlings take root and begin to grow, before the tomatoes bloom and immediately before the first ovaries appear. Add half a bucket of wood ash to 10 liters of water and leave for three days, stirring from time to time. When the composition has settled, the liquid must be drained, its volume brought to 30 liters and 30-35 g of liquid soap added to the composition.

Serum against late blight on tomatoes

Treating tomatoes against late blight with curdled milk serum also gives good results. Dilute the serum in a one to one ratio with water and from the first days of July spray the tomatoes at least every day.

Prevention of late blight on tomatoes

Protecting tomatoes from late blight

It is no secret to any gardener that it is better to prevent a disease than to fight it, even successfully. In order to protect tomatoes from late blight infection, there are effective preventive measures. How to spray tomatoes against late blight? What preventive measures can protect them from infection?

In the photo: Late blight disease of tomatoes

Prevention of late blight on tomatoes in open ground

Dissolve a glass of table salt in 10 liters of water and treat saturated but still green tomatoes with this brine - the composition forms a film on the fruits that protects them from infection.

You can dilute 1 liter of kefir, fermented for two days, in 10 liters of water, mix thoroughly and treat the tomatoes with this composition. The first spraying should be carried out two weeks after planting the seedlings in the ground, and then repeat the treatment of tomatoes with kefir weekly.

Agrotechnical methods of prevention from late blight

If you follow crop farming techniques, you can reliably protect your tomatoes from late blight. Here is a list of activities that serve this purpose:

• in areas with excess lime content, the natural balance of the soil should be restored by adding peat under digging. When planting seedlings, it is better to fill the holes with sand;
• observe crop rotation: do not plant tomatoes in an area where carrots, turnips, cauliflower, beets, cucumbers or onions grew before them;
• do not thicken the plantings - follow the planting scheme developed by agricultural technicians;
• water tomatoes early in the morning or after sunset, trying to pour water so that drops of water do not fall on the plants;
• During periods of high air humidity, tomatoes may not be watered at all, but it is very important to loosen the soil between the rows during this period of time;
• feed the tomatoes with phosphorus, potassium and other useful elements that help strengthen the plant’s immunity - strong, healthy tomatoes are not affected by fungal infections.

In the photo: Phytophthora on a tomato

Prevention of late blight on tomatoes in a greenhouse

Late blight on tomatoes in a greenhouse is almost a more frequent visitor than in garden beds. Prevention of late blight in a greenhouse should begin with disinfection of the room. Before planting seedlings, sanitize the greenhouse: wash away dirt, cobwebs, and remove plant debris.

To disinfect a greenhouse, you can use fumigation: place a piece of clean wool in a bucket of burning coals, place the bucket in the greenhouse and tightly close all windows and doors for a day.

As a preventative treatment for the entire greenhouse and tomatoes, dusting with a mixture of wood ash and tobacco dust is used at the rate of 2 cups of dust per bucket of ash. Don't forget to wear a mask and goggles before doing this.

Instead of tobacco-ash powder, you can use a solution of the drugs Baikal EM, Siyanie or Fitosporin to treat the room in accordance with the manufacturer’s instructions.

In greenhouse conditions, it is better to use drip irrigation to moisten the soil by connecting a special hose to a container with warm water to gradually saturate the soil with moisture throughout the day.

In the photo: Rotting tomatoes due to late blight

Do not forget to regularly ventilate the greenhouse and do not allow large amounts of condensation to accumulate in the film greenhouse.

As for the preventive treatment of tomatoes themselves, in the greenhouse it is carried out at the same stages as in the garden: a week after planting in the ground, before flowering and before the first ovaries appear. If you do everything correctly, these measures will be enough to ensure that you never see symptoms of late blight on your tomatoes.

If late blight does end up in your tomato bed, prepare yourself for a long and stubborn struggle - late blight doesn’t just give up.

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Most summer residents growing tomatoes are familiar with the problem of late blight. It is tomatoes that are more susceptible to the disease than other vegetables, which manifests itself in blackening of fruits and leaves, affecting the amount of harvest.

Late blight always lives in the soil and appears in the second half of summer, when it is already quite cold and damp at night, which means there is a good environment for its development. Now gardeners use both chemicals and various folk methods to combat the scourge. We will look at all the methods in this article.

What is late blight?

If you are not familiar with this disease, then you simply did not grow tomatoes. You need to personally know the enemy by sight, or rather the signs of the onset of late blight, in order to quickly begin the fight against it.

Late blight (or late blight) is a disease caused by a fungus. There are about 50 species of these fungi. The word “late blight” is translated as “destroying a plant.”

Fungi reproduce asexually using spores.

Fungal mycelium lives in the remains of diseased crops, in the soil, in garden tools and, having overwintered, begins its cycle anew under favorable conditions (high humidity is the most important of them).

Depending on the type of fungus itself, there are several types of late blight:

1. Phytophthora cactorum Schroet. Appears on trees of the beech family (oak, beech), pine (coniferous), rosehip;
2. Phytophthora cinnamomi Bonds. Trees of the beech and walnut families are affected by this fungus;
3. Phytophthora infestans. The well-known late blight of potatoes and other vegetables of the nightshade family;
4. Phytophthora fragariae. Raspberries, buckwheat and strawberries are affected. Recorded in North America and Europe. In Russia, cases of infection are rare.

Late blight on tomatoes appears most often at the end of summer. In other words, it is brown rot, which first affects the leaves and then the fruits of tomatoes.

The leaves are covered with brown spots on the bottom.

In the rain, tomato leaves affected by late blight seem to be covered with a light-colored oil film. Tomato inflorescences turn yellow, darken and fall off.

Spots on tomato fruits of different sizes are gray-brown in color. The disease spreads throughout the entire tomato plantation quickly, literally in a couple of days. The bush quickly becomes depressed and gradually dies. Therefore, the beginning of the epidemic is easy to miss.

The first signs of late blight on tomatoes

Late blight is a fungal disease that most often affects tomatoes and potatoes; eggplant and peppers are slightly less affected by it.

Main features:

• The stem of the plant is covered with irregularly shaped brown spots;
• The inflorescences are yellow or dark and fall off quickly;
• There are dark spots on the leaves. Then the leaves dry out and fall off;
• The fruits are covered with gray-brown or black spots.

Photo of disease on tomatoes

Below you can see what the disease looks like on plants in order to recognize it in time.

How does defeat begin?

High humidity is a trigger for the fungus that causes late blight. When moisture appears, the spores first infect the leaves, starting from the bottom.

They become covered with a white coating, which gradually passes to the upper part in the form of brown spots.

Following the leaves, the inflorescences are affected (they dry out and fall off), and then the fruits themselves. Gradually increasing spots of gray-brown color, almost black in places, cover the entire fruit.

The peel becomes thin, and the flesh begins to rot and smell unpleasant. In just a few days, the entire crop is affected by late blight, and without proper attention from the gardener it will be lost.

Causes of the disease

Before you begin to effectively combat late blight, you need to know what causes the disease. Let's look at the main ones that cause late blight on tomatoes:

• Close proximity to potatoes (most often this is where the disease begins);
• Dense plantings and lack of ventilation between bushes;
• A large difference between night and day temperatures and heavy dew in the morning (this occurs more often in August), as well as the absence of heat;
• Frequent and heavy rains in the second half of summer;
• Excessive watering in July-August during fruit ripening, as well as irrigation on the leaves;
• Excess nitrogen;
• Increased lime content in the soil;
• Lack of potassium, copper, iodine, manganese in the soil.

Knowing the main reasons, you can avoid mistakes in care in advance and save your harvest.

What to do if the disease appears in the greenhouse?

In a greenhouse, late blight may not appear on tomatoes with proper care. The main thing is to maintain moisture and heat conditions, as well as to do preventive treatment.

You should not make close plantings, do not plant other tomatoes or potatoes next to the greenhouse in order to reduce the risk of transferring the disease from them to the greenhouse.

It is necessary to water rarely, but in large quantities. Prevention in a greenhouse begins with the disinfection of the premises and equipment. And if late blight gets into a greenhouse with tomatoes, then it develops even faster than in open ground: the warm and humid climate inside it contributes to this.

Measures applicable in open ground

Tomatoes planted in open ground are most susceptible to the fungus that causes late blight.

If agricultural technology has not been followed, then with increased humidity, frequent rains and large amounts of dew, late blight will definitely appear.

Here it is easier to prevent a disease than to try to fight it when it has already manifested itself. When obvious signs are visible, it is already difficult to fight it and a large loss of yield is guaranteed.

Methods and methods of struggle

As soon as late blight appears on tomato bushes, gardeners are faced with the question of how to get rid of the scourge. There are 2 ways to treat late blight:

• Chemical (using drugs containing chemically active substances);
• Folk (food is often used as the main active ingredient).

Important! When processing tomatoes, it is worth processing potatoes, especially if they are planted nearby. Late blight often spreads from potatoes to tomatoes.

Fighting with chemicals

Let's look at the main, most popular drugs among summer residents and gardeners that are used to treat tomatoes.

Spraying with Hom

Hom is a fungicide characterized by contact action. The active ingredient is copper oxychloride, which acts on the surface and does not penetrate into the leaf and fruit.

It is suitable for prevention, protects the plant well, but does not treat an already diseased bush at all.

It is not able to accumulate, which means fungi do not get used to the drug and every use will be effective.

Can be processed up to 5 times per season. Lasts up to 2 weeks, but is easily washed off by rain. Last treatment at least 20 days before harvest. Prepare the solution according to the instructions, dissolving 40 g. drug per 10 liters of water. It cannot be stored. Use in the evening or morning in clear weather. Hazard class - third, requires protective clothing and safety precautions.

Treatment with Furacilin

Furacilin is an antibacterial drug for humans. But many summer residents use it to treat late blight in tomatoes.

The solution can be prepared for the whole summer at once, because... Thanks to its bactericidal properties, it does not spoil. You need to crush 10 tablets and dilute them in 10 liters of water.

You need to spray 3 times a season: before flowering begins, when the first fruit ovaries appear, when the first tomatoes ripen. The drug is not dangerous for humans.

How to treat with Fitosporin?

Fitosporin – It is a biological pesticide that contains bacteria.

The “medicine” penetrates the plant tissue and kills all pathogenic bacteria with the help of beneficial microorganisms.

This drug is biologically safe; tomato fruits can be eaten immediately after washing thoroughly.

It combines well with other chemicals. Suitable for prevention as well as treatment. Features of preparing the solution (2 tsp per 10 liters of water):

• Use warm water no higher than 35℃;
• Do not use metal containers;
• Keep the solution in the sun for several hours to activate beneficial bacteria.

The entire plant needs to be treated. Frequency – every 10 days during the season (if it rains, then immediately after the rain). The drugs Baktofit, Baikal-EM, Fitophtorin, and Planriz have a similar bacteriological composition and method of use.

Use of Trichopolum or Metronidazole

Trichopolum – This is a medicine (antimicrobial and antifungal action) for people with the active ingredient metronidazole (to reduce costs, you can buy a drug with the same name).

Used by gardeners not so long ago.

The solution is made as follows: 2 tablets per liter of water. Treatment - every 10 days or after rain (if tomatoes grow in open ground), since it does not linger on the leaves.

How to overcome Ordan disease?

Ordan – This is a fungicide with 2 active ingredients: copper chloride and cymoxanil.

Penetrates inside the plant, a little remains on the surface.

The therapeutic effect lasts 2-4 days, and the preventive effect lasts up to 14 days.

This is where the frequency of use comes from. Prepare a solution for tomatoes as follows: 25 g. for half a bucket of water (bucket - 10 liters). The fruits should not be eaten for 5 days.

Attention! The drug Ordan has a third hazard class for humans: it requires protective equipment and measures.

Countermeasures using folk remedies

Adherents of natural farming, as well as people who use traditional methods of cultivating the land, but reject the use of chemicals when growing tomatoes, use only traditional methods of combating late blight in tomatoes. Let's look at the most popular of them.

Using whey or kefir

Lactic acid bacteria contained in dairy products suppress the pathogenic flora of late blight.

It is used for preventive purposes and for treatment. The effect of different milk products is the same, although whey gives the maximum effect.

Different ratios to water: whey is diluted 1:1 (or 1:2) with water, a liter of kefir is diluted in 10 liters of water. Instead of kefir, you can take milk and add about 20 drops of iodine. Let the solution sit and then spray. The procedure can be carried out at least every day.

Soda treatment

Soda, a product whose usual place is a kitchen cabinet, can be used for late blight in tomatoes.

In half a bucket of water you need a tablespoon of soda and a little liquid soap for a “sticking” effect.

Repeat every week, or after rain.

Using salt to fight

Salt can fight such scourges as late blight. After it gets on the leaves and fruits and dries, it will cover everything with a thin white layer, which will prevent fungi from entering the plant.

This is only a preventive measure, because... struggles on the surface. For saline solution you need 250 g. dissolve salts in a 10-liter bucket of water. Spray the entire plant. It's worth repeating after the rain.

Vinegar

This product is often used as an anti-phytophthora remedy.

Half a glass of table vinegar (9%) should be diluted in a bucket of water and sprayed over the entire plant.

It is good to alternate this procedure with other folk and chemical methods.

Toothpaste

This unusual method is also used by many summer residents. Toothpaste contains many substances that have a bactericidal effect.

To combat the disease, you need to take a tube of toothpaste and dilute it in a bucket of water.

For convenience, first stir the paste in a small amount, and then combine with the rest of the water. Toothpaste is better suited as a preventive measure. Repeat every time after rain, can be combined with other methods.

Spraying with garlic tincture

Garlic has a strong odor and good bactericidal properties. You can plant garlic along with tomatoes.

To combat the disease, pour 1.5 cups of chopped garlic arrows and heads with 10 liters of water and leave for a day.

Afterwards you need to spray all the bushes with the solution. Needs to be repeated every 2 weeks.

Boiling water (hot water)

The cheapest way. To do this, clean water needs to be brought to a boil and poured into a watering can with a special nozzle in the form of a shower head.

Watering tomato bushes with hot water should be done carefully, raising the watering can higher so as not to damage the plant.

Repeat the procedure once a week.

Interesting! It has been established that spores of a harmful fungus die at temperatures above +30°C

Ash

An ash solution effectively fights late blight on tomatoes.

Need 5 kg. dissolve the ash in 10 liters of water and leave for 3 days, stirring regularly.

After bringing the volume of the solution to 30 liters, add any liquid soap as an “adhesive”.

Spray 3 times throughout the season: a week after planting in the ground, before flowering and after the first ovaries appear. Another way: add a glass of tobacco dust to a bucket of ash. Before use, you must wear a respirator and safety glasses.

Yeast

An almost constant ingredient in baked goods also helps with late blight.

Can be used at the first signs of tomato disease and in advance during the period of ovary appearance.

For this, 100 gr. yeast must be dissolved in a bucket of warm water, let it brew for a while and then spray the entire plant.

Hay protection

Moreover, you need to take already rotten, rotted hay.

About a kilogram of hay needs to be filled with 10 liters of warm water and added about 100 grams. urea.

Leave to infuse for 3 days and then treat the tomato bushes with the prepared mixture. Bacillus subtilis perfectly prevents the development of late blight.

Other ways to combat tomato late blight

There are still ways to treat tomatoes from this scourge. Let's list the main recipes that gardeners use.

Iodine treatment

The well-known antiseptic can be used in combination with other folk remedies (milk, kefir, ash solution) for a more effective fight.

Dosage: per 10 liters of water – 20 drops of iodine.

To strengthen the immunity of plants in greenhouses, you can hang open jars of iodine.

How to treat with hydrogen peroxide?

This is an additional source of oxygen for plants.

It has oxidizing properties and destroys the pathogenic flora of late blight.

Per liter of water you need to add 2 tbsp. hydrogen peroxide and spray the entire plant, especially the lower part of the leaves. Repeat no more than once a week.

How to protect with “Bib” for tomatoes?

This device with a “childish” name consists of covering the soil around a tomato bush with several layers of newspaper, cardboard (or mulching with previously shredded paper).

Bibs allow you to water less, because... retain moisture in the soil in sufficient quantities, which means it does not create excessive moisture. In addition, it prevents the transfer of spores from the soil to the plant itself.

Copper wire against adversity

Copper is harmful to late blight fungus spores. A simple and effective way to combat the disease is to wrap the plant near the root collar with copper wire.

For better results, use a small piece of wire (about 4 cm) to pierce the stem at the base.

The ends need to be bent towards the ground. Copper from the wire will help strengthen the plant’s immunity and prevent late blight from spreading.

Important! The plant itself must already be well developed, otherwise the bush can be ruined.

Potassium permangantsovka

This product has antiseptic properties.

It is good to use together with other folk methods (garlic, ash, milk).

Calcium chloride

Another drug from the pharmacy perfectly fights late blight fungi. It saves fruits well when the leaves are already affected. To do this, dilute calcium chloride with water in a ratio of 1:3 and process the tomato fruits.

How to stop copper sulfate infection?

One of the most popular remedies for treating tomatoes against late blight.

The main active ingredient is copper, which copes well with the scourge.

To prepare the solution, 1 tbsp. add the drug and a little liquid soap to 10 liters. water so that the drug stays on the leaves longer.

Zelenka

An antiseptic in the amount of 40 drops per bucket of water is a good remedy for late blight in tomatoes.

Can be used for prevention and also as treatment.

Boric acid

Attention! The most effective way is to alternate the use of iodine, boric acid, brilliant green, and manganese. Frequency – once a week.

Bordeaux mixture

Another preparation containing copper (consists of copper sulfate and quicklime).

To prepare the solution you need to take 100 g. copper sulfate and 150 gr. quicklime per 10 liters of water, and mix in strict sequence: first copper sulfate in water, and then lime.

The liquid is quite toxic, so you need to use protective equipment.

How to process it correctly?

The basic processing rules are as follows:

• The weather should be clear and calm;
• The best time is early morning or evening;
• If the drugs are toxic, then you need to use protective equipment and follow safety precautions;
• Do not use metal utensils for preparing solutions, especially chemical ones, and mixing devices (preferably plastic, glass, wood).

Varieties resistant to late blight

There are no varieties that, in principle, do not suffer from late blight. There are varieties that can resist it more than others. Most often these are hybrid varieties. For a good harvest, it is worth planting early-ripening tomatoes, the harvest of which can be harvested before massive late blight damage occurs. Varieties resistant to late blight:

• Blizzard;
• Budenovka;
• Kostroma;
• Pink dwarf;
• Parterre;
• Profitable;
• Otradny;
• Dubrava;
• Lark F1;
• De Barao;
• Berry;
• Solar;
• Grotto;
• Snezhana;
• Cameo et al.

Prevention of late blight on tomatoes

To reduce the risk of tomatoes becoming infected with late blight and protect the harvest, you need to carry out competent agricultural practices. Basic Rules:

1. Maintaining tomato crop rotation. Do not plant tomatoes after potatoes, peppers, eggplants, avoid their close proximity. Good predecessors for tomatoes are onions, cucumbers, beets, turnips, cauliflower and carrots. Do not return tomatoes to the same bed before 4 years;
2. The place for tomato plantings should be sunny;
3. Choose varieties that are either early ripening or hybrid varieties that are most resistant to late blight;
4. If there is a lot of lime in the soil, then add peat to the hole when planting, and then sprinkle sand around the bush. Place onion peels into the holes;
5. Don't plant tomatoes too often;
6. You need to water the tomatoes at the root, being careful not to touch the leaves and fruits. In the second half of summer, you don’t have to do this procedure at all (with the exception of intense heat without rain), but only regularly loosen the soil around the bush. It is better to water the plants in the morning so that excess moisture is removed during the day. Drip irrigation is ideal;
7. Mulching bushes;
8. Planting white mustard, calendula, marigolds, as well as onions and garlic next to tomato bushes;
9. Remove shoots and unnecessary leaves in a timely manner;
10. Increase the immunity of tomatoes: fertilizing with potassium and phosphorus, spraying with immunomodulators;
11. Ventilate the greenhouse regularly;
12. Nitrogen fertilizers are appropriate only in the first half of the growing season; the rest of the time, frequent fertilizing with nitrogen will provoke the growth of late blight.

The rules are quite simple. By following them, you can avoid massive damage to tomatoes and even not encounter late blight at all. Any disease is easier to prevent. Then your bed with tomatoes will definitely give an excellent harvest.

Important! Prevention is the best method to combat this scourge. Proper care will help preserve the harvest.

Common mistakes

Most often, the main mistakes lie in the lack of preventive measures to prevent the disease.

• During the outbreak of the disease, you should not water the bushes at all, so as not to increase the humidity.
• Another mistake is using many methods at the same time, especially chemical ones. Surely you will cope and save part of the harvest, but the plants themselves may die, and the fruits may become poisonous due to the large number of chemicals used.

FAQ

Questions about this disease arise frequently. Let's answer the most common ones:

Is it possible to water tomatoes infected with late blight?

If the weather is cloudy and the air temperature is low, it is even recommended not to water the infected bushes. You just need to loosen the soil.

Is it possible to eat tomatoes with late blight?

Tomato fruits with black spots, damaged by disease, few people will want to eat. You should not eat it, even after removing the damaged areas, because... The fungal spores have already completely penetrated the pulp of the fruit. Those tomatoes that have been affected by the fungus only on top can be eaten after heat treatment.

How to preserve fruits damaged by late blight?

You can eat good fruits from an infected bush if they are processed correctly: the fruits should be kept for 10-15 seconds in water at a temperature of 60℃. Afterwards they need to be dried and left to ripen.

How to save picked tomatoes?

Green tomatoes can be preserved for the winter after being well-treated. Red fruits are best eaten immediately or canned.

Useful video

Learn more about late blight control in the video below:

Conclusion

In conclusion, it should be said that the most important thing in treating tomatoes from late blight is prevention. If you take all preventive measures, then problems with this scourge can be avoided.

Which method to choose to treat tomatoes from late blight is a personal matter for each gardener. None of the listed methods guarantees complete relief from the disease. To effectively combat the onset of a tomato disease, it is better to alternate methods and methods so that the fungus does not get used to it and does not develop immunity to the drugs.

Every gardener who has been involved in growing tomatoes in his or her personal plot has encountered such a common disease as late blight. We will tell you in more detail what late blight is and how to fight this common disease with folk remedies.

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Description of plant disease

Late blight or late blight is a fungal disease that most often affects plants belonging to the nightshade family, including tomatoes. Determining the appearance of late blight is not difficult. On leaves, stems and ripening fruits small brown spots appear that increase in size, and the leaves quickly dry out and fall off. Dark spots may appear on the shoots, and on the tomatoes there may be areas of gray-dark stains that soon turn black. The causative agent of late blight is present everywhere in nature; under suitable conditions, this disease develops, which affects tomatoes.

Most often, late blight appears in the month of August, when the heat has already subsided and the average daily temperature is about 20 degrees. It has also been noted that one of the conditions for the appearance of late blight is high humidity, so if the summer turns out to be cool and rainy, then such a pathogenic fungus can appear at the beginning of summer, and the disease rages throughout the growing season.

In dry and hot weather, the fungus that causes late blight quickly dies, and the spread of the disease slows down. Also quite often such brown and dark spots from the fungus appear on the beds in cases where gardeners do not provide appropriate care for the plantings, water them incorrectly, or plant vegetables in the beds without taking into account the minimum allowable distance between plants.

Signs of late blight

If we talk about the signs of late blight, we can note the following:

• The appearance of black areas on the fruits.
• The shoots darken and soon turn black.
• Dark spots appear on the underside of the leaves, and soon the foliage dries out and falls off.

How to treat late blight on tomatoes

The success of combating this fungal disease largely depends on how quickly treatment is started, which will not only save the future harvest, but also quickly get rid of the manifestations of the pathogen. In this case you can use folk remedies for late blight on tomatoes, and spray the plantings with various fungicides.

Important. Late blight on tomatoes, if treated incorrectly or not in a timely manner, will quickly destroy the entire crop.

If we talk about store-bought products, we can note the following fungicides against late blight:

• Bordeaux mixture.
• Thiovit Jet.
• Horus.
• Topaz.
• Speed
• Fitosporin.
• Fundazol.
• Previkur.

However, many gardeners are skeptical about the use of such fungicides, arguing that the use of such chemicals, although it allows one to cope with late blight, has a negative effect on the yield and taste characteristics of the grown crop. Therefore, one should not be surprised by the popularity various folk ways to combat this disease. Such protection of tomatoes from late blight will be effective and at the same time completely safe for the grown crop.

Phytophthora on tomatoes, how to fight with folk remedies

There are various effective folk ways to get rid of late blight on tomatoes. One of the advantages of using such folk remedies to combat this fungal disease is their complete environmental friendliness, which eliminates the accumulation of nitrates, nitrites and other microelements and chemicals hazardous to human health in ripening tomatoes. . We offer you the most common and effective folk methods that will allow you to cope with the fungal pathogen and grow an excellent harvest in your garden.

Garlic-manganese infusion

The fight against late blight on tomatoes in a greenhouse involves regularly spraying the plantings with various infusions. We can recommend you a garlic-manganese infusion. Making such an infusion yourself will not be difficult. You will need the following:

• Potassium permanganate – 1 gram.
• - 100g.

The garlic cloves used should be crushed in a meat grinder, pour a glass of boiling water and leave for 24 hours. After this, filter the resulting infusion, dilute it in 10 liters of water and add 1 gram of potassium permanganate. It is necessary to water the ground with the prepared solution and irrigate the affected bushes.

Straw tincture

To prepare such an infusion straw for late blight on tomatoes, you will need one kilogram of straw or rotten hay, which is filled with 10 liters of water. Add a small handful of urea and leave for four days. All that remains is to strain the infusion and treat the tomatoes with the resulting mixture.

Yeast from late blight

Yeast is a universal nutrition and an excellent opportunity to get rid of various fungal diseases. To prepare such a medicinal solution, you will need to dissolve about 80 grams of yeast in a bucket of water. Immediately after the yeast has completely dissolved, the resulting solution should be watered over the tomatoes.

Copper wire as an excellent way to combat late blight

An excellent alternative for spraying tomatoes with various agrochemicals is the so-called copper piercing. Experienced gardeners are well aware that copper wire, if sanded and calcined in a fire, is excellent against various fungal diseases. The wire must be heated in a fire, and then pierced with it into the stem of a tomato bush at a height of approximately 10 centimeters from the ground. The ends of the wire should be bent down. Remember that wrapping the wire around the stem is prohibited.

Copper wire contains various microelements that enhance oxidative processes, stabilize the production of chlorophyll in plants, strengthen the immunity of tomatoes, which makes such plants resistant to various infections, including the fungal late blight.

Iodine for late blight

Excellent results are shown by treating tomatoes with the first signs of late blight with an iodine-based solution. We are all well aware of the antimicrobial properties of iodine, therefore, by spraying tomatoes with a prepared milk-iodine composition, you can quickly get rid of late blight on your plantings. To prepare such a medicinal solution you will need:

• Water - 10 liters.
• Low-fat milk - 1 liter.
• Iodine - 20 drops.

The resulting solution should be carefully stirred, after which the green mass is sprayed with the infusion and the soil is spilled on the beds.

Ash solution for late blight on tomatoes

This treatment is effective, but only with full compliance with the technology for carrying out such spraying. The treatment is carried out in three stages, so it will be necessary to treat the seedlings that have begun to grow with the prepared ash solution, the second treatment is carried out before flowering, and the third spraying is carried out when the first ovaries appear.

To prepare such a solution, you will need half a bucket of wood ash, which is filled with 10 liters of water. Infuse the solution for 3 days, gently stirring the tincture from time to time. After 3 days, the liquid is drained, after which the volume of the liquid is increased to 30 liters, and 30 grams of liquid soap are added to the tincture. The resulting ash solution should be sprayed onto the plants and lightly moistened the ground.

Whey on yogurt

Excellent results are shown by the use of whey on yogurt, which is applied when the first signs of late blight appear on tomatoes. To prepare such a medicinal solution, it is necessary to dilute the serum in water in a one to one ratio. Also, such a prepared serum solution can be used as an excellent prophylaxis.

Prevention of late blight on tomatoes

Every gardener knows very well that it is much easier to prevent the formation of late blight than to try to fight such a disease in the future. That is why it is recommended to carry out appropriate agrotechnical measures and regularly spray the plantings with various tinctures prepared according to folk recipes.

An excellent way to prevent late blight in a greenhouse when growing tomatoes is to treat them with a solution of table salt. To prepare such a medicinal solution, dissolve a glass of table salt in 10 liters of water. Green fruits and growing tomato bushes are treated with brine. This composition forms a protective film on the stems and leaves of tomatoes, which does not allow infection to penetrate the plants, preventing late blight on tomatoes. Such salt protection, despite its simplicity, is extremely effective and can be used by all gardeners.

Also in open ground and greenhouses, the use of kefir solution shows excellent results. To prepare such a solution, you will need to dilute one liter of kefir in 10 liters of water. Infuse the prepared mixture for 2 days, during which time the kefir will begin to ferment, after which several sprays of seedlings and tomatoes planted in open ground are performed.

Agrotechnical work for the prevention of late blight

It is the provision of proper care for plantings and appropriate agrotechnical work that will protect tomatoes from the appearance of late blight. Such events include:

Conclusion

Late blight is a common fungal disease that often affects tomatoes, causing a lot of trouble for gardeners. The fight against this fungal disease involves treating the plantings with fungicides or various folk remedies. In this article, we told you how to spray tomatoes against late blight, and what agrotechnical measures need to be carried out, which will be an excellent prevention of the appearance of fungus on tomatoes.

Rarely a gardener can boast that he is not familiar with late blight. The fungal disease initially appears on potato leaves, then the infection spreads to tomatoes.

The first signs of the disease- brown spots appear on the leaves and stems of tomatoes, and in wet weather a faint white coating appears on the underside of the leaf. Subcutaneous brown blurry spots form on the fruits, which quickly increase in size and cover the entire fruit. The affected tomato first becomes hard, then softens. Moreover, the infection persists in tomato plant residues.

What should you do if this scourge affects tomatoes?

In rainy and cold summers, preventive measures are especially necessary: Every two weeks, tomatoes are sprayed with preparations containing copper.

The first time - seedlings,

the second - before planting it in open ground,

the third time - two weeks after planting.

If for some reason this was not done, use the experience of the most “advanced” amateur gardeners:

At the first signs of late blight, the bushes are treated with a 10% solution of table salt. As a result, a protective film is formed on the fruits, preventing the penetration of the fungus, the causative agent of the disease.

Fresh kefir will help prevent late blight for quite a long time, which is mixed in a bucket of water (1 liter of kefir per 5-7 liters of water). The resulting solution is sprayed on tomatoes two weeks after planting the seedlings in a permanent place, and then every week.

Speaking about diseases of vegetable crops, first of all it should be said about powdery mildew of cucumbers, which is the scourge of this culture. The disease manifests itself in the form of a white powdery coating, usually on the upper side of the leaf.
At first, the plaque occurs in the form of individual spots, but over time they grow and merge, and then the plaque covers the entire leaf blade. Affected leaves dry out. The harmfulness of the disease increases during dry and hot weather, especially when plants are overcooled as a result of a sharp temperature change at night.

Many vegetable crops (cucumbers, tomatoes, onions, garlic, peppers, etc.) are affected by downy mildew.

Unlike the real one, the false one develops not outside, but inside the plant tissue. The disease manifests itself in the form of spots, rot, and deformation of shoots.

On cucumbers, onions and garlic, the disease is caused by the fungus pores A, hence the name - transporosis, and on tomato - by late blight fungus ( late blight). Due to blight, cucumber leaves become covered with yellow-green spots, which over time turn brown, dry out and crumble. Gray-violet spots predominate on the underside of the leaves. Onion and garlic blight affects from the top of the leaves to the base. On pepper, the disease appears as pale green clearings. Affected leaves wither and dry out.

Late blight of tomato appears on leaves and stems in the form of brown spots, which seem to be bordered by a mold-like coating. In dry weather, the leaves usually dry out quickly, and in wet weather they quickly rot. In this case, the fruits turn black, soften and become unsuitable for consumption.

Tomatoes often suffer from diseases such as blackleg and Fusarium wilt.

The main symptom of blackleg is darkening of the root collar. Its development is facilitated by sudden changes in temperature and increased soil moisture. Fusarium wilt is characterized by damage to the roots: a pinkish or white coating forms on them. Then the plants begin to turn yellow from below and then wither.

How to fight these diseases?

First of all, you should avoid re-growing crops in the same place for 3-4 years. Due to the fact that pathogens persist not only in the soil, but also in plant debris, they must be collected and destroyed in the fall.

Against downy mildew, the seeds of cucumbers and tomatoes should be treated with potassium permanganate before sowing(10 g per 1 liter of water, treatment time - 20 minutes), then the seeds should be washed and dried. It is also necessary to regularly inspect the beds and immediately remove plants with signs of damage.

Another effective measure against powdery mildew, late blight and other diseases is spraying cucumbers, tomatoes and onion sets with one of the following preparations: 1% Bordeaux mixture, copper oxychloride (40 g per 10 liters of water), Ridomil (50-60 g per 10 l of water), foundationol (10 g per 10 l of water), topsin (10 g per 10 l of water), topaz (2 g per 10 l of water). The last three drugs also work well against powdery mildew of cucumbers. When growing onions, spraying with chemicals is not recommended.

Positive results against blackleg and fusarium wilt are achieved by strengthening plant resistance through good fertilizing. Feeding is considered the best from a weak solution of mullein, slurry, chicken droppings, ash lye.

The latter is prepared as follows: two glasses of ash are steamed in 1 liter of boiling water, stirred, left for 6 hours, filtered, and water is added so that the volume of the solution reaches 10 liters.

First, the leaves of potatoes and tomatoes are affected by dark spots, then they begin to turn brown, dry out and fall off. Black spots form on plant stems. Over time, the fruits darken. Almost every gardener has encountered a similar phenomenon. And its name is late blight.

Late blight is one of the most common fungal infections of plants. Translated from Greek, “phyto” means “plant”, and “fluorosis” means “destruction”. Crops belonging to the Solanaceae family are most susceptible to the development of this disease: tomatoes, peppers, potatoes. However, it is possible that the disease may appear on buckwheat, strawberries, and castor beans. The causative agent of the disease is a fungus.

No one will be happy about the occurrence of this fungal scourge. It greatly spoils the harvest of most summer residents. If late blight has settled on tomatoes, not many people know how to fight it with folk remedies, and they quickly buy chemicals, spending a lot of money on them. But today there is no specific way to combat the disease. But people do not give up and continue to try and spray tomatoes against late blight with improvised means. And often this brings positive, albeit temporary, results.

Infection occurs by the penetration of a fungal spore into the plant through the most unprotected place called the stomata. In order for the fungus to get into it, you need water.

The spores have small tails, thanks to which they can move. With the appearance of water (during watering, during rain), the spores penetrate the plant, take root there and multiply. No matter how sad it is, it becomes doomed to death.

Pathogenic organisms overwinter in soil, infected tubers, and tops. The spread of the disease occurs at temperatures above 10 degrees Celsius and humidity above 75%. When it rains, spores are washed off the leaves and stems into the soil. In this way, young potato tubers are infected. In addition, the disease can be spread by wind.

Late blight on potatoes begins to appear in the middle of summer, during heavy rainfall. In dry and hot air, the fungus dies within two hours.

How to treat tomatoes against late blight? - this question is asked every year. In fact, a burning topic. After all, people are waiting for the harvest, but instead they have to watch the plant die. And, therefore, there can be no talk of any harvest. Folk remedies will help eliminate late blight on tomatoes. The drugs have been tested for centuries.

We study the causes of late blight

Late blight, also known as potato rot, is considered the most harmful disease of nightshades. The disease provokes damage not only to foliage, but also to tubers. The main danger of the disease is the enormous speed of its development. Potato rot is caused by:

• sudden change in weather;
• thickened plantings;
• dampness (abundant watering, rain);
• cold dew.

Favorable weather conditions provoke the defeat of all plantings, and in a very short time - one to two weeks. If you do not take any measures to treat late blight, you risk losing more than 50% of your crop. You will learn how to combat late blight on potatoes in this article. There are a considerable number of folk remedies that will help eliminate the disease.

The fight against late blight on tomatoes using folk remedies is also possible. However, before taking action, it is necessary to find out the exact cause of the fungus. Another name is brown rot of tomatoes. The scourge infects all above-ground parts of the plant. Warm, humid weather contributes to the spread of the disease. In most cases, tomatoes become infected with late blight from potatoes.

Late blight, like any other fungus, is ubiquitous and, moreover, tenacious. Its “children” can live not only in the soil, but also on seeds, plant remains, and equipment.

Before answering the question of how to deal with late blight, I would like to talk about what the disease loves. So, the disease affects plants of the nightshade family if:

1. The soil in which they grow is enriched with lime. Most gardeners are terrified of “acidification” of the soil, and therefore oversaturate the soil with lime. However, few people know that it is the best bait for late blight.

2. Treatment of late blight becomes difficult if the plantings are too dense. When a greenhouse with tomatoes becomes like a jungle, ventilation as such does not occur in it. And, as you already know, fungal spores love a moist environment.

3. Plants are weakened. Here, like people, those who have a weakened immune system are susceptible to developing the disease. If vegetables suffer from a lack of microelements, such as manganese, iodine, potassium and copper, it is possible that they will soon get sick.

4. Temperature changes frequently. With sudden changes in temperature (especially at the end of summer, when it is warm during the day and chilly at night, and cold dew falls), the risk of plants being affected by late blight automatically increases.

All this can be prevented. For this it is enough:

• follow the rules of crop rotation;
• plant tomatoes after those vegetable crops that are considered good predecessors;
• watering should be carried out exclusively in the morning (this way the water will have time to soak into the soil);
• regularly ventilate greenhouses;
• do not water plants in rainy weather;
• loosen the soil;
• feed the plants on time;
• periodically spray and water tomatoes against late blight with folk remedies or biological products (what to spray with - watch the video and read on).

Thus, the following is known about the prevention of late blight: the best means of combating the disease in question in crops of the nightshade family is to prevent its development, that is, prevention.

So, to prevent the development of the scourge and harvest:

• avoid planting tomatoes next to potatoes;
• do not flood the plants;
• remove weeds;
• When watering tomatoes, do not wet the leaves;
• if you grow tomatoes in a greenhouse, ventilate it and prevent condensation;
• do not overuse fertilizer with manure;
• Burn plant remains after harvesting fruits, and disinfect greenhouses with lime chloride.

Home remedies to help protect your harvest

Today there are plenty of folk remedies for combating late blight. All of them are effective and efficient and are in no way inferior to drugs sold in stores. However, they must be used with caution. Overuse of recipes can harm plants. To avoid this, try to strictly follow the dosage.

Treatment of late blight with salt. Dissolve a glass of salt in a bucket of warm water. Mix the composition thoroughly. Use the product to treat potatoes and tomatoes. This product will cover the leaves with a protective layer that will prevent spores from penetrating into the plant. However, do not forget that this is a preventive measure, and before starting to treat with the solution, it is necessary to remove all infected foliage.

Ash against late blight. Mix ten liters of water with half a bucket of ash, stir. Leave the container for three days. Don't forget to stir from time to time. After three days, combine the product with laundry soap - 30 g. Next, increase the volume to 30 liters. It is suitable for treating all plants of the nightshade family. The procedure is recommended to be carried out three times per season. The first is after planting the seedlings, the second is before flowering, the third is after the first ovaries appear.

Late blight is afraid of kefir. Dilute kefir in ten liters of water - about a liter. Kefir must be fermented before use. The plant should be sprayed with the drug for the first time 15 days after planting. Further processing is recommended to be carried out once a week.

Application of garlic. Grind the garlic using a meat grinder. To prepare the drug you will need two glasses of raw materials. Combine it with water - ten liters. Leave to brew for a day. Mix the solution with potassium permanganate - two grams. Use the composition to spray plants. The first procedure must be carried out before the appearance of the ovaries, and the second after a week and a half.

Milk and iodine against adversity. Combine low-fat milk - a liter with iodine - 20 drops and water - a bucket. This is an ideal remedy for the treatment of late blight. It is recommended to spray plants twice a month.

Copper piercings. This method is a preventative measure. When the tomato stem becomes strong, pierce it and insert a small piece of copper wire. Before the procedure, heat the wire and clean it with sandpaper. This method helps stimulate the plant's respiratory processes, as well as stabilize chlorophyll levels. All this makes the culture more resistant to various types of infections.

Use of whey. Mix water and whey in equal proportions. From the beginning of July, treat tomatoes with the preparation every day.

Infusion in the fight against late blight. Combine rotten hay - a kilogram with water - 10 liters. Add a handful of urea there and set aside for three days. Use the filtered preparation to treat tomatoes twice a month.

Copper sulfate against fungal infection. Mix copper sulfate in the amount of two spoons with water - 10 liters. It is necessary to treat plants with the composition before flowering.

Use of yeast. Combine yeast - 100 grams with water - ten liters. At the first manifestations of the disease, pour the resulting mixture onto the affected crop.

Manure in the fight against late blight. Dilute fresh mullein in the amount of half a liter in a bucket of water. Treat tomatoes, potatoes, and, if necessary, eggplants and peppers with the prepared solution. Spraying is recommended to be carried out in early and mid-June.

Polypore against fungus. Grind the tinder fungus and brew it with boiled water in the ratio of a liter of water per 100 grams of raw materials. Wait until it cools down and treat the plants with the filtered preparation. Carry out the procedure every ten days.

Use of calcium chloride. In case of severe damage to the tomato by the disease, it is recommended to use the following solution: dilute 200 ml of calcium chloride in two liters of water. This composition should be used to treat the fruits and stalks. Do not neglect the stalks, because they are the conductors of infection.

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The use of the above drugs, compliance with recommendations regarding prevention, proper watering and care of potatoes and tomatoes - all this will help prevent such an unpleasant and dangerous disease as late blight.