White spots on tomatoes in a greenhouse

Tomato white spot (septoria) is a dangerous and common fungal infection. The disease most often affects open ground tomatoes in rainy summers and in regions with high air humidity. But if there are gross violations of crop farming practices, the attack can appear on seedlings, in greenhouses and hotbeds.

The infection cannot be ignored. Septoria blight reduces planting yields by up to 40% and affects the quality of surviving fruits. The pathogen overwinters on plant remains, and in the spring it again infects young tomatoes. To prevent this from happening, you need to take the right measures to treat and protect tomatoes.

Let's understand the reasons: why spots appear on tomato leaves in a greenhouse

It starts with a visual inspection to better understand what exactly happened. Attention is focused on the structure of the leaf, its color and shape. After this, you need to inspect the stem and the area of the seedling located closer to the ground.

If we are talking about insect pests, then characteristic holes will be immediately noticeable. The color of the seedlings will provide some assistance in identifying pests.

Spots on the leaves can occur due to non-compliance with the temperature regime in the greenhouse.
In most cases, the leaves and stem acquire white spots or a slightly white tint.

If something like this is discovered, then you need to delve deeper into the search for the true culprit of the problem:

Mole cricket - an adult individual is characterized by dimensions within 50 cm and a slightly grayish tint to the body. Well-developed paws, which are necessary for the insect to create tunnels, are used as an additional guide. Depending on the availability of the nutrient medium, one individual is capable of laying up to 3 hundred eggs. The mole cricket's nest, the size of which does not exceed 15 cm, is located at ground level.
Scoop - presented in the form of butterflies or caterpillars that are nocturnal. Their activity is noticeable at the level of the root system. In addition, pests actively feed on petioles and leaves. The length of the insect ranges from 25 to 35 cm. The color also varies - from black to gray.
Wireworms - yellowish caterpillars live at the root level, gradually destroying them. The maximum length of the pest is 20 mm. Unlike other insects, the wireworm is easier to notice due to its pronounced yellow color.
Whitefly lives exclusively in greenhouses, where a temperature regime that is comfortable for it is created. Despite being only about 1.55mm long, even a small amount of whitefly can destroy an entire crop. The appearance of black or brown spots on the leaves indicates the need to take emergency measures.

When it comes to pest activity, it is necessary to conduct a visual inspection of the seedlings as much as possible. The changed structure and color of the leaves allows us to draw a conclusion about the type of insect that has settled in the greenhouse. Once the culprit of the problem is correctly identified, you can begin an active fight against it.

Problem two: tomato seedlings turn pale, yellow, leaves dry out and fall off

Is it possible to save already affected plants? It is possible if you transplant them into fresh soil. The roots of each seedling must be freed from the previous soil, make sure that they are white and healthy (if the roots are yellow, black or rotten, the seedlings cannot be saved) and transplanted into light, slightly moist soil. Pour 20 ml under each plant. pink solution of potassium permanganate and place the cups in a sunny window. It may happen that during the transplantation process the roots are damaged and the seedlings wither in the light. Then you should shade them for the first time. But after rooting, good lighting and infrequent watering are mandatory and necessary conditions for the further development of seedlings.

If you follow the rules of watering and your seedlings have enough light, but they still turn yellow or pale, you should pay attention to the nature of the change in leaf color. Perhaps the plant is lacking one or another nutritional element that needs to be replenished

Removing stains on tomatoes in a greenhouse: secrets of killing insects

As was said earlier, before taking any action, you need to know the enemy by sight. If we are talking about a mole cricket, then in this case you need to take a solution of pepper. To prepare it you need 10-15 ml of clean water and 150 g. hot pepper.

To prevent the formation of stains on tomatoes, they should be regularly treated with special preparations.

If you couldn’t find one, you can use two glasses of table vinegar. The prepared solution can be safely used on tomatoes in a greenhouse, because the mixture is environmentally friendly.

The prepared solution must be poured in a thin stream into the insect holes, after which you should wait a few minutes. In most cases, 10-15 minutes will be enough to destroy the pest.

If another pest has settled on the tomatoes, then you need to do the following:

The use of biologically active substances is permitted subject to strict adherence to the instructions indicated on the packaging. The substance is applied pointwise in places where insects are concentrated.
The easiest way to collect caterpillars is to collect them manually in a special container. In addition, it is necessary to regularly dig up the garden. This is done in order to destroy the favorite habitat of the caterpillars - weeds.

Pest control in open ground is carried out in two ways. First, we are talking about using a vinegar or pepper mixture to kill insects. On the one hand, the technique is environmentally friendly, but on the other, the effect is not always noticeable. Secondly, it is mono to use chemicals. They must be used with extreme caution, otherwise they can do more harm than good.

Sunburn

It happens when seedlings cultivated indoors or in greenhouses looked richly green. But as soon as she was taken outside or planted in the garden, she suddenly began to turn pale. Pale spots spread shapelessly all over the foliage. Such lesions mainly occur on the upper leaves. All foliage may lose its color, and only the shoots of the plant will remain in their natural shade. These are real sunburns.

Remember! This happens if the seedlings are not hardened off enough or if the foliage for some reason was covered with drops of water.

Whitened tomato leaves look aesthetically unsightly, but this is not fatal to the plant itself if the damage is insignificant. As a rule, tomatoes return to normal, without any harm to health

bush. Their tomatoes only need to be fed with mineral fertilizers and growth stimulants.

If the seedling is completely discolored, then it is better to dispose of it. It can and will live, but most likely it will not bear fruit. Since it is the green mass of the plant that leads the process of photosynthesis, its disruption leads to slow development of the crop.

To avoid such damage, it is necessary to harden the seedlings for two weeks before planting in open ground. The first days, take them out only in the morning and evening for a few hours, then by the end of the second week you can leave them for the whole day. Plant seedlings either in the evening, when the sun is not so active or on a cloudy day.

Seedling diseases: yellow spots on tomato leaves in a greenhouse

The situation is more complicated when yellow spots appear on the leaves and stem. We can talk about mistakes made at the stage of transplantation or cultivation, as well as the appearance of a fungal or viral pathogen. As in the previous case, a thorough inspection must be carried out before any action is taken.

Late blight, a fungal disease, opens the list of possible causes.

If yellow spots have formed on only one plant, then it should be thrown away immediately.
The first signs appear on the 4-5th day of fungal activity. A slightly brown or yellow color appears on the stems. Gradually the disease moves towards the leaf.

At this stage, it is necessary to clearly distinguish the reason for the change in the shape and color of the leaf plate:

A characteristic sign of a fungal pathogen is the “movement” of the clinical picture from the stem to the edge of the leaf;
Improper watering is typical for those cases when light yellow spots form first at the tip of the leaf and then spread further;

Regular standardized watering, proper feeding, sufficient sunlight and moderate humidity are the key to healthy seedlings. If yellow or brown spots cannot be avoided, then you need to carefully examine the plant. Depending on where the problem is coming from and where it is going, appropriate measures need to be taken.

Solving problems with yellowed leaves

Before you start to fight the problem and save the seedlings, you should clearly understand the cause. Each disease has its own individual symptoms, which can be used to clearly understand the problem.

Diseases of tomatoes in a greenhouse and their treatment When planting tomatoes in greenhouses and greenhouses, we, of course, first of all, dream of an early harvest, and also try to protect...

Insufficient nutrition

Very often, changes in leaf color depend on a lack of certain microelements.

With a lack of copper, but an excess of organic substances, the surface of the leaves becomes speckled with a pale light green or yellowish color.
With a lack of manganese, the lower tier turns yellow, and the new one grows speckled.
A lack of iron will cause yellowing and falling leaves.
With a lack of nitrogen, inclusions of light green or yellow color appear.
With a lack of magnesium, pigmentation is not only yellow, but brown or dark red.

It is very easy to correct such a problem of lack of microelements - just start regularly applying fertilizers, which contain a predominance of the missing microelements.

Burn from direct sunlight

The color of the leaves can be affected by improper lighting. Spots of white or light yellow color can appear either from an excess of direct sunlight or from a lack of it.

With a sunburn, the density of the spots can be completely different: from small specks to large spots that cover the entire surface.

In these places, the tissue dies off completely, which is quite dangerous and can lead to death if the plant is not saved. For faster recovery, you can use the Epin solution, which is sprayed on plants after removing the affected areas. The tomatoes will develop more slowly, but you will still get the desired harvest. The only consequence is that it may ripen a little later than expected.

On a note!

Most often, spots form in those places where water gets during irrigation. Its drops become a kind of lenses. Therefore, when watering seedlings, make sure that water does not fall on the vegetative part of the plant, but is only absorbed into the soil.

To avoid sunburn, you should follow simple care rules.

It is necessary to grow tomato seedlings in the brightest place in the house, and after transferring them to the greenhouse, young bushes are protected from direct sunlight.
Tomatoes should be watered in the evening or in the morning, when there is no scorching sun.
Watering is carried out strictly at the root.

Such simple measures will help to avoid the death of plants from direct sunlight.

High humidity

If the room has high humidity, is not regularly ventilated, or is watered too often, then yellow spots will begin to appear on the leaves. In such conditions, fungal diseases begin to develop.

To correct the situation, it is enough to normalize the watering schedule. Tomatoes need regular, abundant but infrequent watering. It is enough to water the crop 2 times a week.

Brown spot

This is a fungal disease that first affects the lower tier of leaves and then moves up the bush. First, small yellow spots appear, which gradually grow and merge. The fruits of adult plants are not affected. If you do not take action, then gradually all the leaves will turn brown, dry out and fall off.

Action should be taken when spots appear on the lower leaves. They are removed, and the plant should be treated with a biological fungicide. The rules and number of procedures are always indicated in the instructions for the drug.

You can reduce the rate of fungal development by adjusting humidity. When humidity is less than 70%, the development of fungal pores stops. Similar actions are carried out to treat any fungal diseases.

Viral mosaic

The first sign of the disease is uneven coloring of the leaves, yellowish spots and inclusions appear on them. The leaves also curl downward. The affected plant can no longer be saved; it is destroyed so that the virus does not switch to other plants.

As an effective preventive measure, seeds should be disinfected by soaking them in a solution of potassium permanganate. The most common cause of this disease is initially infected seeds.

The main thing for a gardener, if yellow spots or spots appear on the leaves of tomatoes, is to correctly identify the cause and take the necessary measures. The sooner treatment is started, the higher the likelihood that the future harvest will be virtually unaffected.

Removing white spots on tomatoes in a greenhouse

In order to get rid of the problem in a short time, you need to decide on your arsenal in advance. For example, when a brown color appears, the gardener is forced to resort to chemical and biological preparations. When it comes to white spots, a person has more room for maneuver.

Before you start removing white spots on tomatoes, you should watch the training video

It all starts at the stage of selecting seedlings. The healthier they are, the less chance there is of leaf spotting.

In addition, attention should be paid to the following recommendations:

Next to the newly planted seedlings, it is necessary to place a bush of nettle, which has a detrimental effect on the fungus;
It is necessary to water the seedlings based on the information placed on the bag of seeds;
Before planting, it is recommended to test the soil for acidity and nutrient levels;
If nearby tomatoes become stained, they need to be isolated.

Preventive measures

Any interference with the natural growth processes of tomatoes, except for fertilizing, is stressful. Even after a dive, the culture needs some time to recover.

If adult bushes tolerate stress with minimal consequences, then for thin stems, delicate leaves and a fragile measles system, external influences can be disastrous. This does not mean that if infections or other problems appear, they should be ignored. It’s just that the intervention must be justified and targeted. Before starting treatment, you need to accurately determine the problem.

Therefore:

The soil is disinfected before sowing seeds, and not when pests emerge from it, or contaminated soil will cause seedling diseases characteristic of adult tomatoes. Seeds should be treated. It is imperative to adhere to the rules of agricultural technology

It is especially important not to over-moisten the soil, maintain temperature conditions, ventilate the room, and follow the fertilizing schedule. What adult tomatoes can easily withstand can be destroyed by seedlings. You cannot keep seedlings and indoor flowers nearby. It is imperative to carry out preventive treatments - they can be done with gentle preparations

It is recommended to include spraying with Epin and Zircon in the schedule.

Spots on the leaves of tomato seedlings can appear for various reasons: due to pests, fungal, bacterial, viral and non-infectious diseases. They need to be identified promptly and treated correctly. The best prevention is following the rules of agricultural technology, using healthy seeds and high-quality substrate.

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Where do the white spots on the leaves of tomatoes in a greenhouse come from, what to do

Tomatoes are a crop that is demanding when it comes to growing conditions. Any climatic changes, nutrient deficiencies and attacks by pathogens and insect parasites cause stress in plants, which leads to the appearance of pale green or white spots on the foliage. White spots on the leaves of tomatoes grown in greenhouses appear both on young seedlings and on adult bushes. If they are detected, you need to understand the causes and eliminate the problem in a timely manner.

Septoria blight (white spot) of pear (Septoriapiricola Desm.)

Pear septoria is also a widespread disease. Manifestations of the disease are similar to those described above - in late spring, after flowering, small rounded light spots with a dark brown border appear on the leaves of the fruit tree. Sometimes the spots spread to the fruit. In the center of the spots are the fruiting bodies of the fungus with spores in the form of black dots.

The spread of spores occurs most actively in humid, warm weather. By August, the disease reaches mass development and often leads to premature leaf fall, especially in aging and neglected gardens. This, in turn, weakens growth, reduces the winter hardiness of trees, and negatively affects the quantity and quality of the pear harvest.

The pathogen overwinters on fallen leaves.

Prevention and treatment of pear septoria

For cultivation, if possible, select pear varieties that are more or less resistant to septoria: Simply Maria, Hera, Yasachka, Augustow dew, Belorusskaya late, Lada, Vidnaya, Krasny Kavkaz, Chizhovskaya, Nerussa, Severyanka red-cheeked, etc.

Be sure to remove leaf litter and dig up tree trunks in the fall.

Treat your garden with fungicides. Spraying is carried out in three stages:

eradicating (before buds open);
repeated (at the stage of bud bursting, the so-called green cone);
third (after the pear blossoms).

Causes of manifestation

When whitish spots appear on tomato foliage, it falls off after 5-7 days. You should not be afraid of this phenomenon, since the growth point of the bushes is the apical part. However, if the cause of spots on the leaves is not identified in a timely manner, you can lose the entire harvest.

Burns from ultraviolet radiation and mineral fertilizers

Direct sunlight is very dangerous for unhardened tomato seedlings. As a result of exposure to ultraviolet light on an unprepared plant, tissue damage caused by high temperature appears on the delicate foliage. On the leaves they appear as small light spots. Lesions can occur due to improper watering, when residual water remains on the foliage. It focuses the sun's rays onto itself, and as a result, light spots appear, which dry out after 5-6 days. Therefore, watering in the greenhouse should be carried out only in the morning and evening hours at the root of the plants.

The cause of lesions on the tissues of the leaf blade is the contact of a solution of mineral fertilizers or an infusion of cow manure on the foliage during root fertilizing. Saturated concentrates also burn tomato leaves, causing whitish spots to appear.

Symptoms:

after fertilizing or watering when water gets on the foliage, white spots with a light yellow tint appear;
absence of moldy plaque on the stains.

Iron chlorosis

Violation of chlorophyll formation in foliage and iron deficiency are not dangerous diseases. By identifying the manifestations of the disease in a timely manner and taking measures, you can successfully get rid of the disease. A lack of microelements and iron in the nutrition of tomatoes in a greenhouse leads to the occurrence of this disease, which appears on the leaves in the form of white spots. The cause of the development of the disease can also be a high content of lime in the soil.

Symptoms:

large white spots with a light yellow tint appear on the tomato leaf plate, and the veins remain dark green;
at the beginning, symptoms appear on the upper leaves, gradually covering the middle and lower parts of the foliage;
absence of moldy plaque on the stains.

Non-compliance with watering regimes and temperatures

When tomatoes are rarely watered in a greenhouse, the plants quickly become dehydrated and the photosynthesis process is disrupted. At the first signs of disruption of normal growth, the lower part of the plant foliage becomes covered with light spots and dries out. Excessive watering causes oxygen starvation of the root system of tomatoes, as a result of which the lower leaves also become covered with whitish spots.

Sudden changes in air temperature in a greenhouse will cause stress to the plants. This action will immediately affect the condition of the foliage. The leaves will become dull and white spots will form on them.

Symptoms:

the lower leaves of tomatoes become dull in color and whitish spots form on them;
absence of moldy plaque on the stains.

Downy mildew

With increased soil moisture in the greenhouse, as well as an increased nitrogen content, white powdery spots of peronospora fungus appear on the outer part of tomato leaves. The disease is dangerous because its spores, during the process of reproduction, take away all the nutrients from plants and disrupt the process of photosynthesis. The leaves are completely covered with a white coating, wither and fall off. At the same time, tomato bushes sharply lose their immunity and are unstable even to minimal cold snaps.

Symptoms:

white spots with a light yellow tint appear on the lower part of the tomato leaves;
the presence of moldy powdery plaque on the spots;
if treated untimely with fungicides, white spots spread to the upper part of the leaves.

Tobacco mosaic

The cause of infection of tomatoes in a greenhouse with a virus is infected gardening tools, soil and seedlings. The infection develops in greenhouses with poor ventilation and dense plantings and manifests itself in white-yellow mottling on the entire part of the foliage. Further, the leaves become deformed and become thread-like, and the tomato stems break easily. Tomatoes grown from seedlings are severely affected by mosaic. After all, during the growing process, young plants undergo repeated mechanical treatments, during which infection can occur.

Symptoms:

small white-yellow spots appear on all parts of the leaves;
the foliage is deformed and specific growths form on it.

Powdery mildew

The disease is caused by a pathogen such as a marsupial fungus.
The disease looks as if someone bleached the leaves on the bush in pieces or carelessly spilled paint on the plant. Signs of the disease:

Most often, white spots with a gray tint are found on the lower part of the leaves;
sometimes there may be yellow spots on the top of the leaf;
as a result, the leaves burn out from the inside and then dry out completely; sometimes there may be plaque and dots.

This disease often occurs in bushes that are located in open soil or in a greenhouse. The reason for this is sudden changes in humidity and temperature. This disease is quite difficult to fight; the infection quickly spreads through the root system. If it rained too much and then suddenly became warmer, then you need to immediately treat the tomatoes - any specialized preparation like Zineba will do.

The leaves of the seedlings turn white. What to do?

What do I do if the leaves of the seedlings turn white?

Why do tomato foliage turn yellow?

Treatment of the disease

As soon as you notice the first signs of the disease, you immediately need to remove all areas and get rid of them. After this, all tomatoes must be treated with medications such as: Gaupsina, Trichodermina, Zineba. Select one of them and process 1 time. If the disease manifests itself again, repeat the whole process again.

When planting, always treat the plant as much as you can expect; it is best to carry out preventative measures immediately. Use exactly the same mechanism when planting, and especially when transplanting tomatoes.

To be able to fight tomato diseases, the very first thing you must do is understand what exactly you are dealing with, because many diseases can cause spots and white spots on tomato leaves. White coating on plant leaves is always a negative sign that needs to be dealt with.

Treatment

Having established the cause of the appearance of white spots on the foliage, you should begin to combat the problem.

Helping tomatoes get burned

If damaged tissue appears on the leaf plate due to ultraviolet radiation or chemical ingress, the tomato bushes should be sprayed with a half dose of any growth stimulant: Epin, Zircon, Emistin. If subsequently the burn affected most of the foliage, it will be very difficult to save the plant. It will be easiest to dig it up and throw it away, since the yield on diseased plants will be less than 25%.

Treatment of tomatoes with iron chlorosis

The main measure to combat chlorosis is foliar treatment of tomato bushes with iron chelate. Root feeding - copper sulfate. It is also necessary to feed the plants with microelements: boron, magnesium, manganese, zinc, iodine.

Treatment of tomatoes with the appearance of white spots of downy mildew on the foliage

The fight against the downy mildew pathogen should begin at the first signs of the disease and the appearance of small powdery white spots on the foliage. After all, fungal spores can destroy all plants in 6-10 days. To save the harvest, it is necessary to treat tomatoes with the following preparations: M22-VIZR, Quadris, Gamair, Acrobat-MC, Okhsikh, Metaxil.

Treatment of tomatoes with the appearance of white mosaic spots on the foliage

When small spots of tobacco mosaic appear on the leaves of tomatoes, the disease spreads to the rest of the plants very quickly, and it is practically impossible to save the crop. Therefore, the main method aimed at combating infection is disinfecting the soil before planting, treating garden tools with alcohol and treating seeds with fungicides. Treatment of plants with whey with the addition of a small amount of sugar will help contain the spread of the virus. There are no effective chemical drugs to combat infection.

Ways to get rid of the problem

If the cause of blanching of tomato foliage is damage to the garden plant by pathogenic microflora, then it is necessary to immediately carry out therapeutic measures using the most effective drugs. The use of folk remedies in this case is inappropriate due to insufficient effectiveness and a high risk of losing a significant part of the harvest.

Damage factor	Signs of defeat	Standard treatment regimen
White spot	The appearance of off-white spots with a dark border on the foliage	Dilute the drug "Abiga-Peak" at the rate of 50 g per 10 liters of water and treat the aerial parts at the first signs of damage
Powdery mildew	A very pronounced whitish coating of mycelium forms on the surface of the leaves.	Spraying at the beginning of budding and fruit formation with an interval of 7-14 days with the drug “Topaz”, diluted in a ratio of 6-8 ml per 10 liters of water. 5 liters of solution is enough to treat an area of one hundred square meters.
Spotted wilt	Formation of small yellowish-white spots on old foliage	It is recommended to destroy infected plants by digging and burning
Mosaic	The appearance of a yellowish or whitish pattern on the foliage	Burn all tomato seedlings showing signs of mosaic damage.

In order to improve the growth and development of tomato seedlings and to increase overall yield, it is recommended to use the drug “Agat-25K”, diluted at the rate of 140 mg per 3 liters of water. The first spraying of plants is carried out at the stage of the appearance of the third true leaf, and repeated treatment is necessary for tomatoes after about three weeks with a consumption of 0.3 liters for every 10 m 2 of planting area.

Thanks to such treatments, plants grow stronger and are able to actively resist all adverse external influences.

The harvest depends on the quality of planting material. Before planting plants in the ground, their condition is assessed. Often, beginners are faced with the fact that young tomato seedlings grow pale and thin

When such a problem occurs, it is important to know what to do in order to identify and eliminate the causes of unhealthy plant appearance.

Many gardeners believe that such seedlings are too weak and will not be able to grow good tomatoes from them. However, plants can be revived. If you create optimal conditions for them, you can grow excellent bushes from elongated seedlings and harvest an excellent harvest from them. Tomatoes love light and warmth, but do not tolerate drought. Temperature disturbances, moisture deficiency or insufficient lighting affect the appearance of seedlings and their health.

Here are some reasons why tomato seedlings stretch upward and lose color:

Pale seedlings tend to stretch out if they don't get enough light.
The further the seedlings are from the light source, the more they stretch towards it.
Plants actively grow upward when they are planted densely.
The denser the rows of seedlings, the thinner and longer their stems.
The pale green color of plants with elongated stems appears due to an excess of nitrogen in the soil or its deficiency.
The likely reason for the rapid growth of seedlings is the high air temperature in the room, especially at night. The seedlings stretch out at night. If the room is cold at this time, it becomes stronger and grows wider.
Pale leaves of tomato seedlings appear when the watering regime is not followed.
Most often, this phenomenon occurs when there is excess moisture.

To save young shoots, you need to take the following steps:

The lighting needs to be improved. If street light is not enough, you need to buy special lamps. The room needs to be illuminated in the morning and evening. If the light source is fixed, it is necessary to constantly rotate the seedlings to avoid bending the stems. To ensure uniform diffused light, mirrors can be installed.
To make thin seedlings stretch upward less, the base of the stem is sprinkled with soil, and the 2-3 lower leaves are removed.
You can transplant the plant to fresh soil and deepen it to the first true leaves.
Picking seedlings inhibits their growth. Picking is the process of transplanting a plant into a separate container to expand the area. Tomatoes tolerate picking perfectly.
To prevent waterlogging of the soil, you need to water the plants after the soil dries out. However, it should not be allowed to dry out.
You can slow down plant growth using the drug Atlet.

Prevention

To prevent the appearance of white spots on tomato foliage, preventive measures should be taken.

Maintain the air temperature in the greenhouse at +20 - +28 degrees and humidity not higher than 75%.
Provide tomatoes with good ventilation in any weather.
Avoid mechanical damage to tomatoes.
Disinfect the soil and structural elements of the greenhouse after each harvest.
Apply the necessary mineral fertilizers to the soil: nitrogen, phosphorus, potassium.
Select varieties and hybrids for planting in the greenhouse that are resistant to diseases and unfavorable growing conditions.
If signs of an infectious disease are found on the foliage, dig up the plant and burn it.

How to fight seedlings?

Tomato seedlings are vulnerable to a large number of diseases if not properly cared for. With high humidity and high temperatures, white spots may appear on tomato seedlings. Septoria infects seedlings through untreated soil and seeds before sowing.

It is undesirable to combat septoria on seedlings with chemicals, as they can harm those living in the house. Therefore, it is better to remove infected plants, and treat the remaining seedlings with biological agents or traditional methods that are harmless to humans and domestic animals.

Adviсe

By following the recommendations, you can avoid negative manifestations on tomato foliage and also reap a good harvest of fruits.

To prevent tomato seedlings from getting sunburn at the beginning of planting in a greenhouse, young plants are gradually accustomed to ultraviolet radiation. To do this, expose containers with seedlings to the sun for 1.5-2 hours for seven days.
Pathogen spores retain their vital activity in plant debris. Therefore, after the end of the season, burn the tops along with the weeds growing nearby away from the location of the greenhouse.
If weather forecasters predict sunny, hot weather on the day of planting seedlings, you should move the planting to a permanent location for the following days. Under the influence of the scorching rays of the sun, plants will take root poorly and experience more stress.

If all agrotechnical practices and preventive measures are followed, the tomato leaves in the greenhouse will be healthy and retain their green color.

Sunburn

Whitened tomato leaves look aesthetically unsightly, but this is not fatal to the plant itself if the damage is insignificant. As a rule, tomatoes return to normal, without any harm to health

bush. Their tomatoes only need to be fed with mineral fertilizers and growth stimulants.

The main diseases of tomatoes in a greenhouse and methods of combating them

Why can diseases occur in a greenhouse and how can the seedlings be treated to prevent the leaves from curling? The spores can easily survive the winter in plant debris or directly in the soil. The disease can also develop as a result of using untested seeds that are already infected for sowing. Insects also contribute to the spread of diseases.

Danger awaits young tomato shoots at every stage of growth, and in the case of tomatoes, the situation is complicated by the rapid onset of the flowering period, when the use of chemicals is no longer recommended. You can’t sit idly by; after planting seedlings in a polycarbonate greenhouse, you need to plan preventive measures using traditional methods. Among the most famous and simplest remedies:

wood ash;
dolomite flour;
crushed quicklime

To prevent the disease, common products that are found in every kitchen are suitable:

milk (against late blight);
garlic (for fungal infections);
salt (from late blight);
onion peel (from fungus and late blight).

Why do tomato leaves curl or late blight?

The most common disease of tomatoes caused by the development of a fungus. Fungal spores awaken when there is high humidity. If good air circulation is available in the open ground, then in a greenhouse it is very difficult to avoid dampness and a diseased environment is created. In addition, a concomitant factor of the disease is the temperature difference, which is typical for the spring period, when the difference between the night and day indicators is over 10-15 degrees.

dark brown and brown spots on the leaves;
fruits affected by spots;
drying and curling of leaves.

As a preventative measure, it is appropriate to equip the greenhouse with a drip irrigation system. You can get by with a simple invention made from plastic bottles. Having cut off their bottom, you need to place a container near the root zone with the neck in the ground (towards the roots). Carrying out irrigation in this way, evaporation of moisture is practically eliminated, which means it is easier to maintain the humidity level at the desired level.

In addition to traditional methods, special preparations are used:

Brown leaf spot

A disease characteristic of greenhouse plants. It can be recognized by yellow, round, growing spots that first form on the lower leaves of tomatoes. On the reverse side of the affected foliage, a brown velvety coating (fungal spores) is observed.

A little later, the greens dry out and curl, and after some time the plant dries out. The disease often appears during flowering and fruiting. With high humidity up to 95% and insufficient lighting, brown spotting occurs very intensely. If primary symptoms are detected, it is recommended to immediately treat the plants with Bordeaux mixture or Zaslon, Barrier preparations.

Mosaic

A viral disease, the danger of which lies in the absence of treatment. Therefore, it is important to pay special attention to prevention. The affected plant can be easily recognized by its mosaic coloring; the leaves are covered with light and dark green spots, which rapidly increase in size, uniting into large islands. When the first signs are detected, it is recommended to remove the bush and dispose of it. It is advisable to disinfect the landing site with a special solution.

Fruit cracking

Cracks in tomato fruits often form as a result of improper watering. But this is not the only reason. Cracking can be triggered by excessive introduction of nitrogen-containing fertilizers into the soil and improper use of pollination stimulants. Before using any compositions for the garden, you must carefully study the instructions and do not violate the recommended dosage of the product.

White coating or how to treat against rot?

Tomatoes grown in a greenhouse are susceptible to rot. The disease comes in several types, which differ primarily in the area where the plant is affected.

Root rot develops mainly due to improper soil preparation in the greenhouse. This may be an excess of poorly rotted manure, too wet soil, poor drainage or lack of drainage.
Blossom rot is recognized by characteristic spots on the fruit (the disease does not affect the tops). The formation of deformations and spotting of tomatoes is mainly caused by violation of agricultural practices (improper watering, overdose of nitrogen fertilizers, etc.).
Gray rot is recognized by brown wet spots on the stem and foliage. An ash-gray coating indicates sporulation. The disease develops as a result of poor ventilation in the greenhouse with high humidity levels.
Brown rot affects areas near the stalk and fruit. A small spot may be visible on the surface of the tomato, but almost the entire core is rotten. Fresh manure is considered the main causative agent of the disease, so it is not recommended as a fertilizer for a greenhouse.

As a preventive measure, you should regularly spray the beds with garlic infusion, and also dust them with wood ash.

Leaf mold

It is most often possible to detect the first signs of the disease during the flowering period. Light green spots appear on the upper side of the leaf, becoming yellowish-white over time. The affected leaves first turn yellow, dry out, curl, and then die.

Leaf mold

disinfection of greenhouses;
soil replacement (remove a layer of at least 30 cm);
adjusting air humidity in the greenhouse through regular ventilation;
seed dressing;
spraying the beds when the first signs are detected with a zineb suspension or other preparations.

Macrosporiasis

Dry spotting is easy to identify by elongated brown spots on the leaves, stem, cuttings, and stalk. The fruits are covered with depressed brown spots. The main provocateur of the disease is high humidity and poor ventilation. At lower temperatures, the intensity of development of macrosporiosis increases.

If most of the bush is covered with spots, there is no point in saving it. The faster the fungal spores are removed, the less likely it is that the fungal infection will spread to healthy plants.

Among the preparations, it is effective to use Bordeaux mixture.

Features of caring for tomato seedlings to avoid diseases

To prevent the occurrence of diseases and pests, when growing tomato seedlings you should adhere to the following rules:

Tomatoes should only be sown in a sterilized substrate and container. Before the event, planting material should be treated. The soil must have a certain composition and acidity suitable for tomatoes. It is better to use a universal mixture marked “For tomato seedlings.”
Maintain distance between seedlings. Densified plantings interfere with good air circulation and provoke an increase in humidity.
All diseased tomatoes must be removed promptly. Then diseases will not spread to healthy tomatoes.
Near planting, you will need to maintain good lighting and temperature within +18...+22 °C.
Tomatoes should be watered as the top layer of soil dries, avoiding waterlogging. You need to pour water at the root, trying not to get on the stems and leaves. Before the event, the water must be left for 24 hours and heated to +18…+22 °C.

ON A NOTE. You will also need to spray the seedlings with insecticides and fungicides for preventative purposes.

Prevention of tomato diseases in a greenhouse

Many inexperienced gardeners are concerned about the question of what measures should be taken to prevent diseases from affecting tomatoes? An effective protective base is built on prevention, which includes:

compliance with the rules of crop rotation (one crop cannot be planted in one place every year; predecessors are also carefully selected);
autumn digging of the site (preferably just before the frost, so that the larvae and spores freeze out);
thorough cleaning of the garden at the end of the season (plant debris becomes a winter refuge for harmful microorganisms);
soil disinfection before planting;
disinfection of greenhouse surfaces at the end of the season and in the spring;
replacement of the soil layer (performed periodically to renew the soil or after diseases);
treatment of plants with preparations of biological origin (Bayleton, Actellik, Farmaid-3, etc.).

Soil disinfection in a greenhouse
Thanks to greenhouse cultivation, harvesting can begin several weeks earlier than when growing tomatoes in open ground. There are no difficulties in technology, you just need to adhere to generally accepted rules. Then you can enjoy tomatoes to your heart's content in the summer and make preparations for the winter.

Pests of tomato seedlings

In unfavorable conditions, tomato seedlings can be attacked by the following pests:

Name	What does it look like	Fighting methods
Whitefly	A small fly with white wings. Pests can be recognized by a shiny coating covering the upper part of the leaves.	Adult pests can be caught using sticky traps. To destroy the larvae, seedlings should be treated with insecticides “Confidor” and “Karbofos”.
Spider mite	A small pest that is difficult to notice with the naked eye. But his command is indicated by a thin sticky web accumulating in the axils of the leaves.	To kill insects, you can spray the seedlings with an alcohol solution, infusion of garlic or onion. The insecticide "Karbofos" will help get rid of a large colony.
Aphid	Small insects that attack the stems and leaves of seedlings.	Among the folk remedies, tobacco, soap or ash solution helps to destroy aphids. If there are a lot of pests, then you should use the preparations “Ratibor” or “Proteus”.
Cutworm	A moth-like moth. More often it attacks tomato seedlings after planting in open ground.	You can get rid of the pest using the insecticides “Fitoverm” and “Dendrobacillin”.
Sprout fly	The insect resembles an ordinary fly. Its larvae feed on tender shoots and can destroy most of the seedlings.	To prevent the appearance of the pest, it is important to treat the seeds before sowing. To combat insects, you need to use the drugs “Iskra”, “Aktellik”, “Fufanon”.

Classification

Tomato varieties are divided according to the following characteristics:

Type of use: production, juices, canning, canteens, etc.
Fruit ripening period: early, mid-ripening, late.
Growth form: determinate (short), indeterminate (tall).

Tomato is a heat-loving crop. The optimal temperature for development is +23-25 degrees; the plant cannot withstand even short-term frosts. At a temperature of −10, pollen will not appear.

Why do tomato leaves turn white?

One of the most common problems with tomato seedlings is whitening of the leaves. The reasons for this may be different. It is worth considering all cases and knowing what to do if the leaves of tomato seedlings turn white in a greenhouse or on the ground.

Sunburn

First of all, white spots on tomatoes in a greenhouse appear on “unprepared” plants. For example, seedlings were grown at home, and when planted in open ground or a greenhouse, the leaves turned white, although at home the plants could be illuminated by a fairly bright lamp. This situation is associated with ultraviolet radiation. Lamps do not produce such radiation, but the sun does in abundance.

To avoid this, seedlings need to be properly prepared: placed on a window or balcony. At the same time, increase the time spent in air gradually.

The sun can cause burns to seedlings

If the leaves of tomatoes in a greenhouse turn white, you need to remove the damaged leaves. How to revive tomatoes after a burn in a greenhouse: they are opened mainly in cloudy weather, and not for long in sunny weather, and so on until the bush finally adapts. You also need timely ventilation and control of air humidity.

Important: the rest of the plant is not infected from the whitened areas, but the damaged leaves will begin to die over time, taking on some of the nutrients.

Chemical burns

Whitening of the leaves is a consequence of exceeding the permissible dose of the chemical in the water solution. White spots can be large and noticeable; the death of such a leaf is irreversible. To avoid this, you should carefully follow the instructions for using a particular drug.

Note! Watering with some means is only possible in cloudy weather or in the evening. Such substances for some time reduce the ability of plants to resist active sunlight, the result can be either several whitish spots or the death of the entire bush.

Septoria or white spot

A typical fungal disease for tomatoes. Additional symptoms will help identify it: tomato leaves turn white and dry in the greenhouse; curling and rapid withering of the leaves and the entire plant are also observed.

This problem cannot be underestimated; immediate treatment must be started at the first signs. In its neglected state, septoria can destroy about half of the planted plants.

Important! White spotting can spread not only to healthy tomato bushes, but also to other types of plants - gooseberries, currants, grapes, some types of cereals (barley, millet, wheat).

The development of the disease proceeds as follows: small light spots appear, then these areas darken and increase in size, the entire leaf gradually dies and falls off. Hot weather with high humidity contributes to the rapid development of the fungus. It spreads very quickly - it can be spread both by insects and animals, and on the gardener’s clothing or equipment used. As a result, the contaminated area can quickly increase in size. The incubation period for the development of the fungus is from 7 to 14 days.

The best option to combat white spotting is to prevent the disease through preventive work. The first step is preparing the soil. In the fall, you should completely clear out plant debris and plow the soil deeply. Be sure to get rid of weeds.

Helpful advice: when planting tomato seedlings in a greenhouse or greenhouse, you should use soil in which tomatoes have not been grown for at least three years. Plus, be sure to observe the recommended distances between seedlings.

Regular ventilation and disinfection of greenhouses, including frames and coverings, is necessary. Inventory should also be processed. Do not overwater the plants. Pear trees are most often carriers of this disease. Therefore, tomatoes are not planted in close proximity to them.

If the disease is nevertheless detected, the following measures are taken: the infected plant is isolated and subsequently destroyed. The rest are sprayed with solutions of fungicides. It is better if the product used contains copper. It is popular to use Bordeaux mixture or similar products.

Septoria blight or white spot on tomatoes

If the signs of fungal infection are insignificant, you can still try to save the bush. It is isolated and not replanted until the signs of the presence of the fungus completely disappear. It is also necessary to spray with fungicides, copper sulfate, copper sulfate or other similar substances. Copper kills fungal spores. You should also water the soil with the treatment compound in places where fungus is found.

Note! Experienced gardeners recommend spraying their entire plot three times a season if fungus has been detected at least once. The first time was in early spring, before the buds appeared on the bushes. The means used for spraying are alternated so that the fungi do not get used to them.

Fruits with signs of white spotting should not be consumed. If tomatoes are collected from treated bushes, only fruits collected after at least three weeks are used for food. Seedlings should be purchased only from reliable suppliers.

There are no tomato species that are completely immune to Septoria blight. But some varieties are more resistant: Horeb, Ballad, Golden Fleece and several others.

Problems with adult seedlings

Often the leaves turn white due to disease. The disease is indicated not only by white spots, but also by other signs.

Brown spot

Happens at the beginning of fruiting. As a rule, tomatoes grown in a greenhouse suffer from the disease.

the leaf plate below is covered with white “fluff”;
the plaque gradually acquires a dark brown color;
yellow, ill-defined spots appear on the leaves on top;
if the plant is sick for a long time, the leaves curl and dry out.

This is one of the reasons why tomato leaves turn white and dry.

The disease progresses quickly and spreads at high humidity and air temperature. The best prevention is to frequently ventilate the greenhouse and lower the humidity.

At the first signs, tomatoes should be treated with Bordeaux mixture - a solution of copper sulfate in lime milk. The procedure is repeated four times with an interval of 10 days.

White rot

This is a fungal disease that attacks stems and fruits.

plant tissues become soft and slimy;
white mycelium appears on the root collar, stem and at the base of the leaf blades;
The tomato gradually withers and dies.

The disease spreads quickly at low temperatures and high humidity.

Establishing a regime.
Partial or complete elimination of diseased tomatoes.
Treat the cut area with crushed chalk, coal, potassium permanganate solution or copper sulfate.
Spraying with Bordeaux mixture.

Powdery mildew

The causative agent of the disease is the marsupial fungus.

grayish bloom and white spots on the lower part of the foliage;
yellowish spots appear on the leaves on top;
leaves burn out and dry out

Why do the leaves of tomato seedlings turn white? If there is a gray-white coating on the bottom and yellowness on the top, then powdery mildew is the culprit of the disease. The disease progresses with sudden changes in humidity. Tomato is very difficult to treat. It is easier to prevent the problem - during frequent rains, spray the seedlings with Zineb, an effective fungicide.

Trimming and burning diseased parts of the tomato.
Treatment with a solution of “Zineb” or “Trichodermin” (fungicide).

Another name for the disease is white spotting. This is a fungal disease.

at the beginning of the disease - brown marks on the bottom of the leaves;
growth of brown dots into white spots with a yellow frame;
the appearance of dark spots on spots;
spread of the disease to young shoots.

The affected parts must be cut off. The entire bush is treated with Fitosporin, a new generation biofungicide.

Late blight

Another disease that threatens tomatoes. It usually attacks potatoes first, and then moves on to tomatoes.

foliage and branches become covered with brownish spots;
at the bottom of the leaf plate there are white spots in the form of plaque;
brown spots are found under the skin of the fruit;
they grow quickly and cover the entire fruit;
The tomato becomes hard and then quickly turns limp.

The affected parts of the bush must be removed, and the plant itself must be treated with Bordeaux mixture. Fruits removed from diseased bushes should be placed in hot water (from 60 degrees) for a couple of minutes. This is necessary for disinfection, even if there are no visible stains.

So, why do tomato leaves turn white? This can happen for several reasons. The culprit of the problem is often a banal sunburn. This happens after planting unprepared seedlings in a greenhouse or soil.

Various fungal diseases pose a great threat, the most dangerous of which is powdery mildew. To prevent the disease, it is necessary to maintain optimal humidity in the greenhouse or greenhouse, regularly ventilate and periodically treat the bushes with fungicides. If infection occurs, the affected parts are cut off, and the bushes themselves are sprayed with the same fungicide.

Experienced gardeners claim that tomatoes are a strong and resilient crop. Caring for them is quite simple, and the harvest almost always pleases the owner of the site. However, not every beginner achieves good yields. Either pests spoil the seedlings, then diseases appear, or the leaves of the plants turn white. In order to save a vegetable crop in time, you need to have basic skills in caring for an annual plant.

Other diseases and pests of tomatoes

Whitened tomato leaves are not the only problem that can arise in a greenhouse. Infection with one or another type of disease can occur at any stage: from “birth” to fruiting. An exacerbation may also occur during the appearance of flowers, because... at this point, chemical treatment is no longer recommended.

At such a moment, folk remedies are perfect for maintaining the health of seedlings:

Onion peel (with the appearance of fungi, late blight);
Fine quicklime;
Wood ash;
Garlic (for fungal diseases);
Dolomite flour;
Milk and salt (against late blight).

Important! These drugs are not drugs for the treatment of already existing diseases, these are only preventive measures.

The main diseases to which tomatoes in greenhouses and greenhouses are susceptible:

Late blight. Signs: dark spots on leaves and fruits, curled and drying leaves. Spraying plants with whey will help prevent fungal infections, since lactic acid effectively inhibits the development of fungal spores.
Brown spot. Signs: increasing yellow spots on the leaves, appearing from below, and a velvety coating on the inside. Most often it appears during flowering and fruit formation. Plants are immediately treated with Bordeaux mixture.
Mosaic. The disease is caused by a virus. The plant cannot be treated; it should be immediately isolated and destroyed. Disinfect the soil in its place.
Cracks on the fruit. They appear when the bushes’ watering regime is violated or when nutrient solutions are used incorrectly. Be sure to carefully read the instructions for each drug.
Mold. Discovered during the flowering period. Prevention includes timely ventilation, disinfection, periodic removal of at least 30 centimeters of soil in the greenhouse, treatment with a solution of zineb suspension or analogues.

Septoria blight (white spot) of raspberries and blackberries (Septoria rubi Vest.)

For raspberries and blackberries, Septoria blight is one of the main widespread diseases (along with anthracnose and didimella). First, the leaves, and then often the stems of the plants, become covered with small dark spots, which over time grow and become lighter in the center. Black sporulation spots form on the spots. In case of severe damage, the buds and leaves turn yellow and die, the shoots dry out, the bark of the remaining ones cracks and peels, the bushes as a whole weaken and lose their ability to produce crops.

The pathogen overwinters in the form of fruiting bodies in the form of small black dots on the affected areas of the shoots.

Prevention and treatment of raspberry and blackberry septoria

Plant new plantings only with healthy planting material.

For cultivation, if possible, select varieties that are more or less resistant to septoria (visually their shoots are often covered with a waxy coating): Peresvet, Zaryanka, Sokolenok, Lazarevskaya, Illuziya, Rannyaya Zarya, Arta, Follgold, Espe, etc.

Avoid thickening the bushes. To do this, carry out sanitary pruning of bushes in a timely manner.

How to properly prune raspberries in spring, summer and autumn
We tell you how to properly prune raspberry bushes throughout the season.

Do not overfeed plants with nitrogen fertilizers.

For prevention, treat shrubs 3-5 times per season with an interval of 7-10 days with Fitosporin (dissolve 5 g of powder in 10 liters of water).

Before the buds open, for the same purpose, spray raspberries and blackberries with 1% Bordeaux mixture or a 0.5% suspension of copper oxychloride.

Immediately remove and burn infected shoots and leaves in the early stages of disease development.

Treat shrubs with fungicides according to the three-step scheme described above.

Disease Prevention Measures

There are several ways to minimize problems with tomatoes. These include:

Compliance with crop rotation - do not plant the crop in the same place as last season.
Deep digging of the area before frost;
The soil should be disinfected with special preparations before planting;
Treatment of all plants on the site with natural-based preparations.

So, knowing what to do if the leaves of tomatoes in the greenhouse turn white, you can try to save the crop. Tomatoes are considered an easy crop to grow. Nevertheless, they require care, feeding, and care from the gardener. You should definitely familiarize yourself with the rules and basic care tips, then even a beginner in gardening will be lucky to reap an excellent harvest.

Causes of white spots

Even though tomatoes are an “easy” crop, sometimes problems can arise with them, especially if they are grown in a greenhouse, although a greenhouse is a one hundred percent guarantee that the crop should definitely grow. But sometimes, due to the fact that there may be temperature changes and poor ventilation in the greenhouse, a number of problems may appear. Most often this happens due to the fact that they are exposed to the sun's rays, and were not previously prepared for this. Tomatoes have very tender leaves.

If these are sunburns, they usually only affect the upper leaves of the plant. In addition, this can happen due to the fact that the seedlings were not previously prepared for planting in the ground. Therefore, in order to avoid this, the first seedlings must be kept outside in the sun for at least several hours a day so that they get used to it. If this is not possible, then you can put them on the windowsill, where you can leave them for the whole day.

If you have not done this, then it is best to immediately cover them for the first time when planting, so that the sun does not hit the plant. During the first 11-15 days, the bushes will get used to the soil, and it is possible that they may not like it and then white mold may appear as a “protest” to the soil.