Treatment of fusarium wilt of tomatoes: description and photo of dry rot on tomatoes, what to do to prevent it, how to fight it and how to choose resistant varieties?

Fusarium wilt: description and photo

Fusarium wilt of tomatoes is a dangerous infectious disease caused by fungi of the genus Fusarium. The pathogen lives in the soil and infects plants through young roots or damage to the stem. The fungus is resistant to unfavorable environmental conditions, so it can survive in the soil for years.

The fungal disease has other names - dry rot and fusarium wilt. They were obtained due to the underlying symptoms of the infection. Tomatoes wilt, flowering deteriorates, foliage turns yellow and falls off. If you cut the stem, you will find a dark ring. This means that dry rot has already affected the root system and irrevocably destroyed the plant.

Young and weakened plants become victims of fusarium wilt . The disease develops due to:

sudden temperature fluctuations;
lack of nutrients;
damage by insect pests;
increased soil and air humidity.

The development of fusarium intensifies if tomatoes receive excess nitrogen fertilizer, or a large amount of phosphorus accumulates in the soil.

Symptoms and causes of tomato fusarium

An infected plant can be identified by several signs, including drying, curling and falling leaves. The bush begins to rot from below; after the small roots, large branches are affected. The plant withers and dies.

Vegetable culture can be caused by the following factors:

planting density;
excessive moisture;
lack of light;
contaminated seed;
incorrect dosage of nitrogen fertilizers.

The fungus enters the plant through wounds and cracks. The sooner treatment begins, the greater the chance of recovery. It should be noted that fusarium blight on tomatoes cannot be eliminated. This incurable disease can only be stopped.

Diagnosing the disease is not difficult: just make an incision on the stem of the plant. If tomatoes are affected by Fusarium blight, brown and yellow streaks will be visible on the cut.

Reasons for appearance

Microorganisms clog the blood vessels of tomatoes, disrupting their metabolism. The vital activity of the mycelium leads to the accumulation of toxic substances in tissues, followed by dehydration of tomatoes. Here are the main reasons for the appearance of fusarium:

The seeds or purchased seedlings were not treated . Planting material or seedling substrate may already contain dry rot pathogens. The vegetable grower needs to disinfect the seeds or roots in a special solution.
During pinching, a dirty tool was used , or rough tillage occurred. Inaccurate weeding or loosening is a direct path to damage to the roots. Through wounds, the pathogen penetrates into tissues.
Improper preparation of compost, organic mulch . Once in the fertilizer or mulch mixture, the fungus instantly “eats” the plants.

Fusarium wilt in the active stage of development can affect neighboring vegetable crops. For example, potatoes. You should know the first signs of a fungal disease and take timely measures to destroy it.

Symptoms

The first signal that something is wrong with the plants comes from the leaves. The color of the leaf blades changes from intense green to yellowish. Chlorotic spots appear on the surface of the leaves of the lower tier, and at the same time the veins become lighter.

The petioles become fragile, change shape, and then the leaves curl. Following the lower ones, the upper leaves begin to dry out and wither.

The lower part of the tomato stem becomes brown, and a brown coating (Fusarium spores) is visible on the root collar. Gradually, the upper shoots and leaves begin to fade, and the skin of the fruits on the bushes becomes covered with a whitish coating. The stem of such plants is easily pulled out of the soil; the cut reveals dark brown vessels clogged with fungal spores. It is impossible to save the bush at this stage of damage; it is carefully removed from the ridge and burned.

Signs and similar diseases

Fusarium is insidious and dangerous . Inexperienced gardeners often confuse it with vertillus wilt (wilt), which develops very quickly (tomatoes die in 2-3 days). Symptoms of wilt resemble those of fusarium, but differ in the development cycle. Inadequate treatment leads to an even greater deterioration in the condition of the plants, as well as a significant loss of personal time.

Here are the main signs of dry rot:

It appears only on stepchildren crops that have entered the fruiting stage.
Fusarium develops from bottom to top . The first symptoms of the fungus can be found on the adult lower leaves. Leaf blades lose turgor, become yellow, and fall off. The disease continues to move to the next tier of the plant.
Very often there is damage to one side . For example, the leaves of a tomato wither and turn yellow, and the side shoots only on the right side.
Wilting of the tops . They look “exhausted”, but retain their natural color. It seems that the plant has not been watered for a long time.
The conduction system is affected . When cut from a lifeless leaf or shoot, the tissue acquires a reddish-brown tint.

There are cases when tomatoes are affected by several types of fungus:

fusarium wilt;
fusarium rot of roots and root collars.

The following picture is observed: the root collar is covered with brown areas, the roots are covered with red-brown damage.

Attention! Fusarium can only be detected during flowering and fruiting of tomatoes. It is at these stages that Fusarium wilt gains momentum.

Treatment options

The problem of treating fusarium-affected tomatoes is the absence of signs of the disease at the initial stage. Obvious external changes in the condition of the bush are observed only at the middle stage of infection development, more often during flowering and fruiting.

Some gardeners do not try to treat fusarium and try to get rid of bushes affected by the fungus by removing them by the roots and disinfecting the soil. If you intend to save the harvest, you can try to save the tomatoes using biological preparations and chemicals.

Biological drugs

Biological preparations significantly reduce the consequences of damage to bushes by fusarium, but must be used in combination with chemicals, because have predominantly preventive properties rather than therapeutic ones.

Biological compounds have a beneficial effect not only on plants, but also on the soil layer.

Trichodermin, Baktofit, Fitosporin and Previkur are used to treat diseased tomatoes. The main conditions for their use are temperatures above 18 ° C and humidity within 65-70%. Dosage for root watering and foliar spraying is 20 g per 10 l. Consumption rate – 0.5 l per 1 m².

Stages of development

The infection affects tomatoes in the following stages:

The roots suffer first. The fungus poisons young and tender roots with mitocoxins. The underground part rots and the apparently healthy plant falls to the ground.
Gradually, the fungus moves higher and higher through the vessels of the stem. Tissue blockage occurs, the leaves wither at the base of the stem, become watery at the edges, and acquire a pale green or yellowish tint. If the humidity is high, then the leaf plates become covered with a whitish coating.
The toxins completely destroy the plants and eventually they die.

The plant resists dry rot from several days to 2 months. At a temperature of +16°C, tomatoes die much faster. The development cycle of the disease is from 7 to 30 days, and depends on the composition of the soil, environmental conditions, age and variety of tomatoes.

If the fight against fusarium wilt is not started in a timely manner, then in 2-3 weeks all plantings will die.

What kind of disease is this

Fusarium is a dangerous fungal disease of tomatoes that is resistant to chemicals . Its distribution indicates errors in growing plants. The disease can be encountered both in greenhouses and in open ground in all climatic regions. It may take 2-3 weeks from the onset of the disease to the complete death of the plant.

How does it affect tomatoes?

The fungus attacks the vascular system of seedlings, as a result of which the roots and fruits begin to rot, and the plant itself begins to dry out. The photo shows that the disease spreads from bottom to top. The fungus can be found in the soil and enters the plant through damaged or small roots. As the disease progresses, rot appears on the root system, and fungi penetrate through the vessels into the stem and leaves.

The first sign of Fusarium wilt of seedlings is the falling of the lower leaves. However, this symptom is characteristic of many other ailments. Fusarium is accompanied by discoloration of the petioles and curling of the foliage.

Experienced gardeners have noticed that most often the disease affects plants grown in greenhouse conditions. However, if all conditions for tomato growth are met (temperature, humidity, lighting), it can be avoided. Fusarium wilt is also typical for seedlings grown year after year in the same place.

How to fight?

There are various ways to prevent and treat Fusarium wilt of tomatoes.

Agrotechnical methods

It is important to follow the rules of crop rotation . They consist of regularly changing the site for growing tomatoes. Tomatoes can be planted in their original place after 3-4 seasons. Choose soil for planting this vegetable crop after cabbage, pumpkin, and cucumber. It is unacceptable to plant tomatoes in place:

potatoes;
pepper;
eggplant;
physalis.

If it is not possible to plant tomato seedlings in another place, then you should choose varieties that are resistant to fungal infections.

Moderate fertilizing promotes good plant health . Before planting seedlings, the soil must be fertilized with compost or manure. If there are no organic fertilizers, then nitrogen-containing preparations would be a good option.

Overflow should not be allowed. Too wet and not dried out soil near tomatoes is a favorable environment for the development of fungus. It is recommended to regularly ventilate the greenhouse and water the bushes only as needed.

Folk remedies

It is important to understand that “grandmother’s advice” is not effective against fusarium in advanced stages. The following folk recipes are good because they can slow down the development of the disease:

Wood ash . It is enough to dust the bushes with dry ash, or prepare an infusion. Recipe: 1 tbsp. Pour the ash into a bucket of water and mix. Application: water each bush with this solution - 0.5 liters of mixture for 1 bush. Apply once during the flowering and fruiting periods of plants.
Garlic tincture . Chop the head of garlic and add 1 liter of warm water. Leave the product to infuse for 24 hours. Then dilute 10 liters of water and thoroughly spray the tomato bushes. Apply once a week.
Milk serum . Well suited as a prophylactic agent. Recipe: add 20 drops of iodine to 1 liter of whey, and then dilute the resulting mixture with 10 liters of water. Spray the bushes with the prepared mixture once a day in the evening, throughout the development of tomatoes.

Treating infected tomato bushes is always difficult. Experienced gardeners recommend treating them with modern chemicals.

Chemicals

Initially, you should carefully examine the diseased bushes, remove and burn the affected areas. Then prepare the preparations. Here are the most effective of them:

Bayleton . Recipe: dilute 1 g of the drug in 1 liter of water. Treat the bushes by spraying no more than 2 times during the entire period of tomato growth. It should be sprayed in the evening or early morning. The cost of the drug varies between 250-900 rubles.
Quadris . Suitable for spraying greenhouse tomatoes. Preparation: dilute 40 ml of fungicide in 10 liters of water. The consumption rate is 5 liters of solution per 1 hectare of plantings. Repeat treatment after at least 2 weeks. The price of the drug starts at 400 rubles.
Fundazol . Recipe: dilute 1 g of the substance in 300 ml of water. Then bring the resulting solution to a volume of 1 liter. Spray the bushes with the resulting mixture 2 times throughout the growing season.

Use fungicides strictly according to instructions. During the process of processing tomatoes, it is necessary to protect the eyes, skin of the hands and respiratory tract with special means - a mask, gloves, a respirator, and so on.

Biological drugs

The best drugs against Fusarium wilt are:

"Trichoderma veride";
"Trichodermin";
"Planriz."

The infection is destroyed by the fungi Trihoderma lignorum and bacteria Pseudomonas fluorescens . Experienced gardeners recommend pouring ready-made solutions at the root of the bushes. Here are some recipes:

Dilute 30 g of Trichoderma Veride in 15 liters of water, and pour the prepared solution over vegetating tomatoes once. Pour 1 liter of mixture under each bush.
Dilute 20 g of Trichodermin with 10 liters of water, and pour 1 liter of the prepared solution under each bush. Watering should be done once a week.
Dilute 1 g of Planriza in 10 liters of water. Water the tomatoes every week, starting at stage 3 of the true leaf.

Fusarium on flowers

Asters

Almost all annual asters have insufficient resistance to Fusarium diseases. Flowers are affected by the fungus at the stage of bud formation or at the beginning of the opening of the calyx. In sick asters, the foliage curls, the buds droop, and brown oblong spots or black veins appear on the stems. Brown stripes form on the surface of the root collar. The shoots are deformed due to tissue destruction. The root areas become overgrown with a whitish coating from mycelium or pinkish tubercles. Such a plant may not survive to flower, and if the aster begins to bloom, it is extremely undecorative. The culture lags behind in growth, the buds quickly fade. The causative agent of gray mold penetrates through the roots and moves higher through the vascular system, which by that time is already functioning intermittently.

Lilies

The plant is afraid of moisture and loves dry, sunny places. Mechanical damage to the roots and waterlogged soil are the main causes of gray rot. When the spores spread throughout the bush, the buds begin to fall off and the bulb may die. Rodents, insects, water and wind are considered carriers.

Infected lilies have brownish trunks, and rot is noticeable on the rhizome and bottom. The bottom gradually dies off, voids form inside the bulb, and ulcers and yellow-brown spots appear on the surface. Rot affects both the inside and outside of the bulb, as well as the base of the stem. Heat and high air humidity are the main factors contributing to the development of the disease. A diseased plant lags behind in growth; the higher the healthy bushes rise, the brighter the contrast becomes.

Orchids

Gray rot on orchids can develop over months, but its last stage is truly fleeting, when within a couple of days, due to the disease, the leaves rapidly turn yellow and their leaves begin to fall. A distinctive sign of fusarium will be the presence of a crimson ring on the cut and the appearance of red-brown areas on the aerial roots. A diseased flower must be isolated, since the spores of this rot can easily be transferred to a neighboring flowerpot. A feature of the treatment is dry resuscitation and treatment. In this case, moisture on the leaves and soaking are contraindicated. Fundazol is diluted with water and applied as a paste to the affected area.

Fusarium Signs of fusarium. how to cure a plant

Prevention measures

Preventing a disease is much easier than treating it. There are several proven prevention methods that help reduce the likelihood of dry rot occurring on tomatoes. Let's take a closer look.

Compliance with crop rotation

Tomatoes are planted in a new place every year, but do not forget about the basic rules of crop rotation. In autumn it is necessary to clean the area:

remove tops and old weeds;
add organic fertilizer to the soil and dig deep.

If the nightshade crop is grown in a greenhouse, then the top layer of soil is replaced annually.

Tillage

To make the soil suitable for growing tomatoes, some measures should be taken:

The substrate should be rich in calcium and its acidity should be neutral.
Add dolomite flour or crushed chalk to the soil in any quantity, and then dig everything thoroughly.
Water the soil with a solution of copper sulfate (dilute 70 g of the product in a bucket of water).
In mid-summer, water the tomatoes once with a weak solution of potassium permanganate and boric acid (dilute 1% potassium permanganate and 5 g of boric acid powder in a bucket of water).
In the fall, add 100 g of lime to the soil for every 1 square meter. m. At the same time, water the dug up soil with a weak solution of potassium permanganate.

Spud up growing bushes with plenty of soil , and mulch the space around them with black film. Maintain the temperature in the greenhouse:

during the day – +22-24°C;
at night – +8-16°C.

Ventilate the room regularly.

Disinfection of planting material

Dip the roots of the seedlings for a few minutes in the antifungal solution. For example, in the powder preparation “Trichodermin”. Dilute the powder in an amount of 10 g in 1 liter of water, and dip the seedlings into it.
Dry the roots slightly and plant them in the ground.

Disinfection during bush formation

The infection penetrates the plant structure through the wounds left after pinching. For this reason, pinching should be done with tools treated with a 5-10% solution of iron sulfate or dark pink potassium permanganate, which will prevent the tomatoes from becoming infected with dry rot. Then you should wipe them with a dry cloth.

Resistant varieties

If cases of fusarium infection of tomatoes have already been noticed on the site, then for subsequent planting it is recommended to choose the following varieties:

Jamaica F1;
Tango F1;
Merchant F1;
Fontana F1;
Aurelius F1;
Alexa F1;
Reflex F1.

It is important to understand that without additional preventive measures there will be no 100% result.

Preventive measures

In the fight against disease, infection prevention measures come to the fore. It is necessary to create favorable conditions for the development and growth of tomatoes and exclude comfort for the reproduction of pathogens.

On a note! The result is brought by comprehensive measures when everything is taken into account: agricultural technology, disinfection, selection of seed material.

Basic Rules:

Growing tomato varieties resistant to Fusarium wilt and having a resistance gene. Among them: Kupets, Testi, Vologda, Spartak, Blitz, Sorento, Lastochka.
Treatment of seed material before sowing (treating with Fundazol, Strekar).
Soil disinfection. Before planting, water the beds with copper sulfate (70 grams per bucket of water) and an aqueous solution of potassium permanganate. To till the soil in the fall, prepare a lime solution and add ash.
Adding dolomite flour (on acidic soils), which eliminates the development of fungus.
Deep digging of ridges in the fall.
Mandatory removal of plant residues after each weeding and fruit harvesting.
Disinfection of greenhouse structures and gardening equipment.
Maintaining rotation of garden crops. The place where tomatoes are planted is changed every year, observing the principle of compatibility of vegetables. If it is not possible to change the ridges, then the top layer of soil is removed, replacing it with a new one. You cannot plant tomatoes after vegetables from the nightshade family. The best predecessors: cabbage, cucumbers, pumpkin.

To sow seeds for seedlings, prepare the soil in advance by steaming it in the oven or over a fire. You cannot take land to grow seedlings in greenhouses. Purchased mixtures or turf and leaf soil specially prepared in the fall are suitable.

Indeterminate tomatoes need to form bushes, remove shoots and leaves. Procedures must be systematic so that the crop does not become stressed after pruning. Scissors and knives are disinfected before each use, otherwise there is a risk of fungal spores being transferred from infected bushes to healthy ones.

In greenhouses, relative humidity is maintained, preventing fluctuations in indicators. On hot days, they open the windows and doors, creating drafts for the crop.

Bushes removed from the ridges are burned; they cannot be put into compost. Sick tomatoes are a source of infection, so when they fall into a compost pit, all layers of future fertilizer become infected. Using such compost on beds means reintroducing the infection to the area.

Many crops are susceptible to fusarium, and insects from cabbage can easily transfer the pathogens to tomatoes or potatoes. Carriers of infections are aphids, thrips, and whiteflies, so by destroying pests, gardeners simultaneously save the area from a dangerous disease.

Advice from gardeners

Here are some recommendations for combating fusarium from experienced vegetable growers.

Plowing the soil . In late autumn, it is necessary to loosen the soil with a plow to a depth of 20-25 cm. This will solve 90% of all problems. Fungi and some types of insects overwinter deep in the soil. During late plowing, the earth turns over and frost can kill all pests.
Temperature regulation in greenhouses . Too hot a summer is another reason that affects the deterioration of tomatoes. The way to solve the problem is to whiten the glass surfaces of greenhouses.
All attention to the rains . If a gardener cares about his harvest, he should tirelessly spray the plantings with preparations after each rain. It is rain that is the trigger that activates Fusarium wilt. Many gardeners believe: “If you missed processing after the rain, you’ll be in trouble.”
Treatment of water for irrigation . Typically, summer cottages are located far outside the city, where there is no city water supply. Gardeners water tomatoes with rainwater or from natural reservoirs. Before watering, add Fitosporin-M to the water and leave for 20-30 minutes.
Regular inspection of other plantings on the site . Dry rot can affect flowers, vegetables, trees and shrubs. Sick plantings are dug up and destroyed.

Fusarium is an extremely unpleasant and dangerous fungal disease. It is very difficult to fight him. It is necessary to learn to recognize the first signs of the appearance of dry rot on the site, and to take appropriate measures to destroy it as quickly as possible. This is the only way a person will be able to harvest a rich and healthy harvest of tomatoes.

Potato varieties resistant to fusarium

Currently, there are practically no potato varieties that are highly resistant to dry rot. But it should be noted that this fungal disease begins to affect plants closer to the middle of the summer season, so it is recommended to grow early varieties of this vegetable crop to avoid the appearance of signs of fusarium on plants.

Potato varieties with the greatest resistance to fusarium:

Luck;
Riviera;
Karatop;
Timo and similar varieties.

Treatment of fusarium: list of effective fungicides

The following fungicidal agents are used to treat seeds, seedlings and substrate against fusarium:

Agat-25K is a biological product that has a balanced composition of macro- and microelements, contains pine extract and chlorophyll-carotene paste. It increases yield, has a destructive effect on fungal pathogens of the genus Fusarium and improves soil quality.
Fitosporin-M is a drug of natural origin that serves to protect soil, compost, and planting material from fungal and bacterial diseases.
Baktofit is a broad-spectrum fungicide for the prevention and treatment of fusarium, responsible for the development of healthy microflora, prevents the manifestation and suppresses pathogens of a wide range of plant diseases.
Trichodermin is widely used in agricultural technology, increases soil fertility, protects seeds from fungal infections before planting in the ground, suppresses the growth of fungi and completely destroys them.
Vitaros - used for disinfection of planting material and processing of bulbs and root crops before sending them for storage.
Potassium humate is a fertilizer based on humic acid, peat and brown coal, has effective fungicidal properties, stimulates the growth of vegetative mass.

Protecting your garden from diseases: 3 modern effective biological agents

Folk remedies

A plant affected by fusarium cannot be cured with folk remedies, because the disease can only be detected when it has already gained strength. However, they are suitable for preventive treatment of soil and healthy bushes. The most effective folk remedies are the following:

35 drops of iodine are added to a liter of milk and 25 grams of grated laundry soap are added there. This mixture is used to treat bushes.
1 tbsp. combine wood ash with 2 liters of water, and also add 1 tbsp. l. grated laundry soap. The mixture should stand for 2 days. Then the bushes and the soil surface around them are treated with it. After 7 days, repeat spraying is carried out.
A couple of handfuls of onion peels are combined with 10 liters of just boiled water. The infusion will be ready in half an hour, after which it is filtered. The product is diluted with water 1:1 and the bushes are watered with it from a watering can.
One garlic head is crushed and combined with 1 liter of water. The infusion will be ready after 24 hours; all you have to do is strain it and dilute it with nine liters of water. The bushes are treated with the product the next evening.