Types of tomato leaf curl and methods of treating the disease

Tomatoes, regardless of whether they are greenhouse or not, can be susceptible to various diseases. Diseases can be viral, fungal or bacterial. One of the most dangerous viral diseases is chlorotic leaf curl. A sign of the disease is a change in the color of the leaf blade. From a rich green color it turns into a pale light green or even yellowish.

Signs of defeat

Chlorotic leaf curl of tomatoes manifests itself as follows:

1. Tomato foliage changes color, its edges become lighter than the central part.
2. The leaves begin to bend and curl.
3. The growth of the tomato bush stops.
4. The green mass of the bush becomes smaller, and the shoots become bare.

Tomato leaf curl: symptoms and characteristic manifestations of infection

Yellow leaf curl of tomato: photo of virus

The main symptoms of infection of tomato bushes with chlorotic curl are the following characteristic signs:

• Due to disruption of the chlorophyll formation process, tomato leaves gradually change color from dark green to yellow.
• Often, plastic leaves do not turn yellow entirely, but only at the edges.
• The contours of the leaves are deformed. They themselves become smaller, begin to curl into a tube, and the tops of the bushes become curled.
• A plant affected by the virus begins to lag behind in development, weakens, or even stops growing altogether, which makes it significantly different from neighboring bushes.
• The green mass of tomato bushes is thinning, the stems are becoming bare in places, and some shoots are left completely without leaves.
• Flowering occurs unevenly. Some inflorescences cannot stay on the diseased shoots and fall off.
• Even if the ovaries form, they quickly harden and remain small. Further fruit ripening may not occur.
• The foliage of tomato bushes not only changes color, but also wrinkles.

On average, about a month passes from the moment a plant is infected with a virus until the first characteristic signs of infection appear. Tomato leaf curl infection occurs throughout the growing season.

Despite the comparative rarity of the disease, in conditions of its epidemic spread, significant damage to the crop can be caused. The loss is, at best, 17% of its total volume; in the worst case, complete loss of fruit is likely.

Chlorotic curl of tomatoes affects not only tomato plantings. Other nightshade crops, as well as varieties of lettuce, are also susceptible to this disease.

At the moment, not a single hybrid tomato variety has been developed that would be immune to the leaf curl virus. Therefore, the disease threatens any vegetable farm.

Types of disease and photos of plants affected by yellow and other forms

The disease can manifest itself in different ways. Here are the main types of chlorotic curl in tomatoes:

1. Chloride curl - the disease is characterized by such a course: the leaves change color, in the center it may remain unchanged, but the edges turn yellow and curl. The bush stops growing altogether, the shoots become bare, and the green mass of the bush becomes scarce.
2. Yellow curl - with this type of virus, fruiting of tomatoes stops completely. Flowers fall off and fruits do not set well. The leaves become deformed and fade, becoming cup-like.
3. Top curl is caused by insect pests - beet leafhoppers. Within a few days after infection, characteristic signs of the disease appear: the plant begins to wither, the leaves thicken and curl at the edges. Usually the leaves mutate only at the top of the tomato bush, and the bush itself becomes pale in color.

Next you can see what the affected tomato bushes look like in the photo:

Symptoms

The main symptom of the disease, as already mentioned, is a change in the color of the tomato tops: from the usual dark green it becomes yellowish. It often happens that the color of the leaves changes only along the edges - but in the center the leaf remains the same color.

In addition, the top of the tomato bush is curling. The leaves in this area are bent and curled. Plant growth also stops or slows down significantly. The affected bush, in addition, lags far behind in development from its “brothers” in the garden.

The green mass becomes very small, the shoots are partially exposed. The flowers cannot stay on the stems and fall off. The ovaries, which, despite everything, were able to form, become hard, small, and with the further course of the disease they remain so. The leaves, in addition to changing color, also become wrinkled.

But how to use serum for cucumbers and tomatoes against aphids, and how effective this product is, is indicated here.

Let us additionally note that the chloritic curl virus can infect tomatoes throughout their growing season, and the first symptoms of the disease can be noticed a month after direct infection. Most often, the disease is transmitted through the soil, so usually a month after placing the tomato seedlings in the soil, the gardener notices the disease in the tomato seedlings.

Crop losses in the case of tomato infection by the chloritic curl virus range from 17% in the mildest case, when the infection was quickly stopped, and up to 100% in the most advanced cases. In addition to tomatoes, chloritic curl is also dangerous for potatoes, petunias, and salad crops.

To understand how to grow a good tomato crop, you need to know that in addition to soil and seeds, the virus is also transmitted by the greenhouse whitefly pest. But the disease cannot be transmitted mechanically, which stops the large-scale spread of this disease throughout our gardens and greenhouses. Today there are no tomato hybrids that are resistant to this disease. Therefore, all farmers are equally at risk for chloritic curl.

How does the disease develop and why is it dangerous?

The main symptoms of the disease are curling and curling of the leaves, yellowing begins in the interveinal space, and a purple color is observed in older leaves. If infection occurs in the early stages, then the plant’s vegetation is delayed, growth slows down, and deformation of the bush is observed. Fruit set also deteriorates.

The danger of the disease is that chlorotic curl not only completely kills the plant, but also spreads to neighboring tomato bushes, thereby destroying the entire crop.

It is almost impossible to cure a viral disease, so the diseased plant must be removed from the garden along with the roots. After which the remaining soil is disinfected.

Causes of tomato infection

This disease can be spread by pests - greenhouse whitefly. A bush can become sick because it was grown from an infected seed or because bushes that had been attacked by a virus grew on the site before it was planted. Afterwards, no disinfection or prevention work was carried out in this area. Extensive actions of the pathogen by mechanical means are impossible. Having the opportunity to get to the surface of the plant, it finds ways of possible development even in an unfavorable environment for the bushes, weakening the immune system:

• the irrigation technique does not meet the requirements;
• temperature graph with max and min values;
• insufficient supply of fertilizers;
• plantings are thickened.

Treatment

Let's consider what control measures will help cope with yellow curl and its other types.

To combat the disease, the bush is sprayed with medicine against various insect pests, especially against the main carrier of the disease - whiteflies.

If there are obvious signs of disease, the bush will have to be dug out of the ground. With part of the soil, the plant is completely burned. After this, foliar treatment of the remaining healthy tomato bushes is carried out. To do this, take 1% Bordeaux mixture or copper sulfate. After a week or a little more, the treatment is repeated.

Tomato curl: treatment

Tomato leaf curl: photo of the virus

As a rule, the yellow curl of tomatoes reveals itself when the infection has already largely engulfed the plant. In this case, the treatment will not produce results or will require unjustified efforts and costs. Therefore, it would be more advisable to remove the diseased plant from the garden.

Then it must be destroyed. This will reduce the risk of infection spreading to neighboring tomato bushes. The algorithm of actions when working with infected bushes involves the following steps:

• Before you start working, you need to take care of personal protective equipment - rubber gloves are required.
• A diseased tomato bush should be removed along with the root system, without leaving shoots in the soil. It is necessary to remove fallen leaves and shoots from the garden bed. All this must be burned, since the virus can survive in plant debris.
• Using parts of an infected plant to make compost is strictly contraindicated.
• The place for burning infected plants should be located at a considerable distance from the beds.
• The remaining tomato bushes should be treated with a solution of Bordeaux mixture (1%) or copper sulfate.
• Garden tools used during work must be thoroughly cleaned and disinfected. Ethyl alcohol is ideal for this purpose.

In cases where the plant is infected to a small extent, you can limit yourself to removing infected leaves and shoots. And treat the remaining part of the bush using the means described above. Torn leaves and shoots should be burned.

Tomato watering mode

One of the factors that significantly influences the risk of developing chlorotic leaf curl of tomatoes is the level of air and soil humidity in the area with tomatoes. Compliance with the watering regime is extremely important, especially for tomatoes grown in greenhouses.

Preventive treatment of plants against tomato curl virus

Tomato leaf curl: photo of the virus

As mentioned above, the quality of the seed plays an important role. Preventive treatment of seeds, as well as seedlings and even soil is necessary to prevent them from becoming infected with the virus.

Disinfecting seeds is quite simple. They can be placed in a solution of potassium permanganate before sowing. It is used to spill the soil before planting and spray the seedlings.

Since the carrier of the virus is the whitefly, it is necessary to take timely care to protect tomato plantings from this dangerous pest. You can recognize it by its rather harmless appearance. The whitefly looks like a small white moth.

To prevent its penetration into the area, beds with tomatoes should be periodically treated with insecticides. In gardening stores you can find a fairly large number of effective chemicals.

Those gardeners who do not trust ready-made preparations have several folk recipes to choose from. For example, infusions of garlic, tobacco chips or dandelions are suitable. You can scare away the whitefly using a fumigator, or vice versa - lure it using a trap and then destroy it.

Another preventive measure that increases the immunity of plants and their resistance to diseases is spraying the bushes with copper solutions.

Tillage in tomato beds

Caring for the soil is no less important than caring for the seed and the tomato bushes themselves. The necessary soil treatment measures include the following procedures:

• Such a simple event as deep digging up the soil on the site and regularly loosening it helps to destroy a significant part of the causative agents of viral, fungal and bacterial infections.
• Compliance with crop rotation rules will also reduce the risk of infection. Since replanting the same crops on a site increases the likelihood of transmitting the virus to tomato bushes planted in the new season. Therefore, it is necessary to alternate the placement of certain crops on the site.
• In cases where it is not possible to change crops on the site, it is recommended to replace the soil and first carry out a disinfection procedure.
• Too high a planting density is not desirable, as it increases the risk of developing a virus epidemic. Maintaining sufficient distance between tomato plants will provide them with a degree of protection from infestation. The optimal interval between bushes is 0.5 m.

At the moment, preventive procedures are the most effective means of combating the tomato chlorotic leaf curl virus, since it is practically untreatable.

Combating high humidity in a greenhouse

The virus spreads well under certain favorable conditions. One of these conditions is high humidity. Therefore, be sure to regulate watering, but do not overdo it, especially if the tomatoes are growing in a greenhouse. In hot weather, plants are watered every 2-3 days, but you still need to check the soil before watering. If it is still damp, then postpone this task until the soil is completely dry.

What to do if the leaves of tomato seedlings curl

Before taking any action, you need to find out the reason why problems arise and eliminate it.

First, you should check how moist the soil is, and whether there are any punctures or spots on the leaves that indicate damage by diseases and pests. It is also necessary to take a closer look at exactly how the leaves are deformed.

Why do tomato seedlings curl their leaves inward on the window?

When grown on a windowsill, seedlings often experience a lack of light, because in the spring the weather is often cloudy. And because of this, plant leaves curl and become paler.

You can also notice that the seedlings are stretched and their stems are thinning.

What to do

You will need to move the planting to a brighter place, for example, on a southern windowsill. It is also necessary to provide the seedlings with additional illumination with a phytolamp in cloudy weather, as well as in the morning and evening.

REFERENCE. For normal development, seedlings require 12-14 hours of daylight.

Tomato seedlings have leaves curling downwards

The leaves of tomato seedlings can curl down for several reasons. And all of them are associated with improper care of plants.

Overwatering

If seedlings grow in too wet soil, their leaves often curl down. And, if the situation is not corrected urgently, crops may become infected with blackleg, a fungal disease that is difficult to cure.

What to do

Watering must be completely stopped until the soil dries out. You should not move the plant closer to warmth or direct sunlight, as this will worsen the problem. In the future, you will need to normalize irrigation and do not forget to drain excess moisture from the pan.

IMPORTANT! Tomato seedlings can only be watered with settled, filtered water at a temperature of +20…+25 °C.

Lack of nutrients

The lack of one or another element manifests itself in different ways:

• With a lack of phosphorus, the leaves of the seedlings curl down and acquire a purple tint.
• If plants do not have enough boron , then yellow-orange spots form on the plates.
• Zinc deficiency is manifested by the fact that only the apical leaves of seedlings curl.
• Potassium deficiency can be recognized by curled ends as well as slow development.
• With a lack of copper, the leaves curl into a tube and acquire a bluish tint.
• If plants do not have enough iron , then they not only become deformed, but also turn yellow.

What to do

To correct the situation, you should feed the crops with preparations rich in the elements they need. It is necessary to feed tomato seedlings in the early morning or on a cloudy day. Otherwise, burns will form on the leaves.

Excess nitrogen

If there is a lot of nitrogen in the soil, the leaves of the seedlings curl into a ring and the stems become very thick.

What to do

To help the plants, you need to water them abundantly. Then some of the nitrogen will leave the top layer of soil with water. Then potassium sulfate or a solution of wood ash should be added to the soil. These fertilizers will help balance the chemical composition of the substrate.

The leaves of tomato seedlings curl upward, what does this mean?

This behavior is often associated with errors in care and inappropriate living conditions.

Insufficient watering

If seedlings suffer from a lack of moisture, they roll their leaves upward. This is how plants try to reduce moisture evaporation.

What to do

Tomato seedlings need to be watered urgently. In the future, it is necessary to normalize irrigation, preventing the soil from completely drying out.

Insufficient air humidity

If heating devices are running in the room, the air becomes too dry. And to reduce moisture evaporation, seedlings twist the plates upward.

What to do

Where tomato seedlings grow, humidity should be maintained at 60-70%. To do this, it is easier to install a humidifier near the planting. Water containers will also help.

Fever

If the tomatoes are hot, their leaves curl into a boat. This happens more often if the planting is on a southern windowsill or near radiators (heating devices).

What to do

To correct the situation, you need to shade the plants during the midday hours. Near planting, it is necessary to maintain the temperature within +18…+20 °C. To do this, you should ventilate the room more often and cover the batteries with a damp towel.

What to do if the leaves of tomato seedlings curl and wither

This is how tomatoes often react to pest invasion:

• Aphid. Small bugs are white, gray or brown. They often accumulate in the axils of the leaves, but gradually spread to the petioles and stems. They can be seen with the naked eye, but their appearance is also indicated by deformed shoots.
• Spider mite. A microscopic parasite that is difficult to see without a magnifying glass. His command is indicated by the deformation of the leaves, black and yellow dots on the plates, and a thin sticky web accumulating in the axils.

What to do

To destroy pests, seedlings should be treated with insecticides, for example, Fufanon, Akarin or Biotlin. You will need to spray the above-ground part of the crops, being careful not to get it on the ground.

Treatment should be carried out early in the morning or on a cloudy day. If there are a lot of pests, then you will need to repeat the procedure 2-3 times with an interval of 7-10 days.

Why do only the tops of tomato seedlings curl?

If only the tops of seedlings curl, this may be caused by the characteristics of the variety. But this behavior is a sign of illness:

• Mottling . Translucent spots covered with an oily film form on the leaves. They increase in size and cover large areas. As a result, the leaves curl and die.
• Curly virus. The disease is spread by pests, and when infected, the leaves of the plant become smaller, wrinkled and turn pale.

What to do

To treat mottling, you need to use copper sulfate or Fitolavin solution. If the seedlings are affected by the curl virus, they cannot be saved. To prevent the disease from spreading, it is important to immediately remove all affected specimens.

Preventive treatment of tomatoes and soil

In order to correctly carry out preventive measures against chlorotic leaf curl of tomatoes, it is necessary to know the mechanism of infection. Any gardener knows that when pinching, the disease can be introduced through an untreated tool for cutting shoots. It is advisable to cut tomatoes by hand, without pruning shears.

Another route of infection is through seeds and soil. The main advice here is to be sure to disinfect the seed before planting. And water the soil with the addition of drugs with antagonistic bacteria. Such measures are especially necessary when growing tomatoes in greenhouses.

You also need to know the rules for caring for tomato bushes. This is, first of all, compliance with the temperature regime, moderate pinching, thinning of plantings, etc.

Tomato curl: etiology of the virus

Tomato leaf curl: photo of the virus

Of all the diseases that affect tomato bushes, viral infections are considered the most dangerous and practically untreatable. Often the only solution for the owner of problematic tomato beds is to destroy the infected bushes. They not only have to be dug up and removed from the site, but also burned.

In this way, it is possible to prevent the spread of the disease to epidemic proportions, when there is a risk of losing the entire tomato harvest this season. Chlorotic leaf curl of tomatoes is just such a dangerous and practically incurable disease.

Chlorosis is an indispensable companion to this disease. The process of chlorophyll formation in the leaves is disrupted, which leads to their deformation, growth retardation, and color change. If in the normal state, tomato foliage is colored in a rich dark green color, then chlorotic foliage has a pale color of light green, or even yellow.

As for the shape of the leaves, the top of the bush really begins to curl - hence the name of the disease. In general, all processes in the plant are inhibited, it looks weak and sick.

The source of tomato leaf curl disease is most often a virus - “Tomato leaf curl virus”. The history of its study began in the early 90s, when Californian vegetable growers first encountered it.

The tomato curl virus spread rapidly and already in 1994 was discovered in Central Asia, on the territory of Turkmen vegetable farms. After another 3 years, the virus reached the Mediterranean and began to infect greenhouse tomato plantings in Italy.

Tomato curl is not one of the most common diseases of this crop, but it poses a serious threat to the crop. Despite the fact that no cases of mechanical transmission of the virus have been recorded so far, it has many ways of spreading.

Infected seed and soil remaining after infected tomato plantings retain traces of the virus and are a source of damage. The tomato curl virus is transmitted by insect pests - whiteflies, which themselves can cause damage to the crop, but as carriers of diseases they become even more dangerous.

Destruction of parasites

When fighting parasites, it is important to prevent the creation of conditions conducive to their reproduction, namely:

1. High humidity.
2. Excess of fertilizing.
3. Lots of weeds.
4. Lack of soil disinfection before sowing.
5. Overcompacted soil, lack of loosening.

Against whitefly, which is most often the cause of curling tomatoes, a product such as “Phosbecid” is used.

Agrotechnical techniques

Proper care of tomatoes will also help in the fight against the disease. Here are the agricultural techniques used when growing these plants:

1. Regular loosening of the soil, removal of weeds.
2. Maintain a distance between plantings, which should be at least 0.5 m.
3. Crop rotation.
4. Add fertilizer in the required quantity.
5. Changing the place of planting tomatoes every other year, with mandatory pre-treatment of the soil with a solution of potassium permanganate.
6. It is advisable to plant onions or garlic next to tomatoes, which are good at repelling harmful insects.

General recommendations

To reduce the risk of contracting the virus, in addition to the above remedies, the following preventive measures are used:

1. Change of growing location. You should not grow tomatoes in one place year after year, the beds need to be swapped, but the soil must first be spilled with a weak solution of potassium permanganate before planting.
2. Maintaining distance when boarding. The minimum distance between neighboring bushes should be no less than half a meter.
3. Loosening and weeding the soil from weeds.
4. Planting garlic and onions next to tomatoes. Because of the pungent odor, insects will not attack tomatoes.

If curling is detected, treatment measures should be taken as early as possible. At warm temperatures and in humid conditions, the virus infects healthy plants at high speed, and every day the chance of salvation decreases. To avoid having to deal with infection, be sure to resort to preventive measures and monitor the condition of the seedlings daily, especially in the first half of summer.

Use of chemicals

To control pests that cause tomato curl, fungicides are used, which can be useful only for minor signs of the disease and as preventive measures:

1. Copper sulfate is a reliable means for treating plants against diseases and pests. Costs approximately 187 rubles per kg.
2. Double blow - it is diluted in water, you will need 30 g of the drug per 10 liters of water. The product is effective against many diseases and insects. Its cost is within 45 rubles.
3. Skor is a systemic fungicide that can protect tomato bushes from the spread of the virus and the insects that carry it. The onset of action of the medicine is 2 hours after use, the duration of action is 7-10 days. The cost is within 50-65 rubles.

Why do tomatoes have curly tops: care mistakes

Curly tops of tomatoes can be observed in both seedlings and adult plants. Changes in air temperature and insufficient watering are the most common causes of leaf curl. At air temperatures above +30 degrees, the plant is forced to curl the leaf blade to reduce the area of ​​evaporation. The lower leaves in this case remain normal, since they are less illuminated by the sun's rays. Tomatoes respond in the same way to insufficient moisture.

In this case, it is recommended to take the following measures:

• organize regular ventilation of greenhouses and greenhouses, especially on hot days;
• increase air humidity using water sprays;
• the greenhouse roof can be covered from direct sunlight with any non-woven material (spunbond, lutrasil);
• Place a layer of hay or straw on top of the dark mulch.

When watering, it is necessary to take into account that the root system of the plant lies deep, so moisture should be abundant and not superficial

The top leaves of tomatoes begin to curl into a ring when there is an excess amount of nitrogen fertilizer. In this case, the plant exhibits thickening of the stem, excessive juiciness and fragility of the leaves. Potassium supplementation can help correct the situation:

• add one glass of wood ash to 10 liters of water and water the tomato bushes with the prepared solution;
• potassium sulfate is dissolved in water (1 teaspoon of fertilizer per 1 liter of water). The resulting solution is used to spray the leaves.

Prevention measures

The following measures will help avoid tomato bush disease:

1. Selecting early-ripening tomato varieties so they ripen before the virus spreads.
2. Crop rotation.
3. Treating the soil with Fitosporin, which is destructive to viruses, fungi and bacteria.
4. Water the seedlings at the root part so that moisture does not fall on the leaves.
5. If tomatoes grow outside, then in case of sudden temperature changes, cover the plants with film at night.
6. Weed control.

Non-infectious causes of leaf curl

There are other motives for curling tomato leaves without being killed by an infectious virus. However, there are options for irreversible losses of tomatoes, due to the fact that the surface becomes smaller, the leaf plates begin to receive much less sunlight and have ceased to produce the components necessary to ripen.

The cause-and-effect relationship of the appearance of curliness is a set of other factors:

1. In our greenhouse, when the outside temperature is high, there is a lack of moisture, causing deformation of the leaves. They suddenly began to curl up into a tube to their full length. How to help a poor plant? Using a spray gun, we make a shower for the tomatoes and try to systematically ventilate the greenhouse.
2. Choose tomato varieties that can withstand drought.
3. There is an increase in green mass in other parts of the plant. The root cause is excess nitrogen in the soil and the ration of fresh fertilizer from manure is not maintained when planting the bush. Experienced gardeners in their recommendations advise making a thorough fertilizing from rotted compost. Before the start of the autumn period, feed with potassium and phosphorus.
4. Curling of leaves is directly related to the lack of a substance loved by tomatoes, such as phosphorus. When picking, when seedlings begin, it is imperative to feed young plants in the form of superphosphate. During the season, carry out the operation of fertilizing the beds with phosphorus mixtures several times.
5. A lack of potassium in the soil also contributes to the curling of leaves towards the center of the plate, curling of new leaves and insufficient ripening of fruits. The appearance of yellow spots on tomato sides. Replenishing the presence of potassium is one of the tasks of a caring gardener.
6. Growing bushes in soil rich in peat causes a shortage of copper. Without this chemical element, flowering will not begin at all or will be weak and not distributed over the entire area. The only correct way out of this situation is fertilization with a solution of copper sulfate, or mixtures containing copper.
7. Yellow curl is often caused by excess moisture in the soil plus nitrogen content. The leaves at the bottom begin to curl.
8. The passion for feeding mullein also contributes to curliness. It is introduced at the peak of tomato flowering. It is much better to use potassium and phosphorus.
9. A lack of P2O5 causes purple veins to appear on the surface of the leaves. Water no more than once every two weeks. In a greenhouse, the H2O consumption will be 10 liters, in open beds - up to six liters.
10. Failure to comply with the rules of pinching on the regular removal of formed shoots. Often gardeners cut off the lower leaves along with the shoots. The tomato is in a stressful state, nutrition becomes intermittent, which affects the remaining foliage and inflorescences, which spread like a carpet due to the fall.
11. If you are late to remove the stepsons, disturbances in the metabolic process occur, leading to deformation of the leaves. Stepping should be done when the length of the side shoots is 1.6 - 3.5 cm. Be extremely careful and a sense of proportion obviously will not hurt, do not remove more than 2 - 3 leaves from 1 bush. It is better not to water the plants, but to make the wounds heal better, spray them with the Zircon biostimulator

Virus-resistant tomato varieties

If, when purchasing seeds, you read on the packaging about 100% disease resistance, know that this is just an advertising ploy. There are no tomato varieties that are completely protected from viruses, bacteria and fungi, as well as harmful insects.

It is possible to distinguish hybrids that begin to bear fruit early and have a certain percentage of guarantee that the disease can be avoided:

1. Charisma F1.
2. Vologda F1.
3. Ural F1.
4. Firebird F1.

All of them grow well in greenhouse conditions.

Every gardener must understand that it is better to prevent a disease than to treat it. First of all, this concerns chlorotic curl, which cannot be treated at all. Practice preventive measures and your efforts will eventually bear fruit.