Control measures and prevention of stolbur (phytoplasmosis) of tomatoes. Control measures, signs and treatment of the infectious disease of tomatoes stolbur How to treat tomatoes from stolbur

stolbur on tomato

What does a tomato pillar look like?

A characteristic symptom is obvious deformation of the generative organs. Shoots of diseased plants recede under acute angle, upper leaves usually have pink or purple shade, the lower ones are yellow-green. The leaf segments become smaller, become rough and brittle.

Greening or sprouting of flowers is also observed. The petals and sepals grow and grow together along their entire length, the flower is directed upward and resembles a bell in shape.

Such plants no longer bear fruit.

Infection with stolbur can also occur when there are already ovaries on tomatoes. In this case, the fruits have a yellowish-orange color, develop hard, woody, and unsuitable for food.

Where does stolbur come from?

More common in southern regions V open ground. The causative agent of stolbur is phytoplasma, affecting plants Solanaceae family. But the carrier of this infection is the cicada. In the spring, a few days after feeding on infected weeds, leafhoppers become able to transmit infection to tomato plants, as well as other plants of the nightshade family.

The period of mass emergence of the first generation of leafhoppers is the end of May. They are able to tolerate stolbur infection for 2.5 months. The peak number of leafhoppers is the first half of July.

Phytoplasma overwinters in the rhizomes of affected weeds and other perennial plants(bindweed, thistle, plantain, St. John's wort, elderberry, etc.).

Stolbur is not transmitted through seeds; the causative agent of this disease is not stored in them.

Column of tomatoes photo

How to deal with it

For preventative purposes, remove weeds from the site, especially those mentioned above. Although leafhoppers can easily fly from one area to another, carrying the infection.

You need to do everything possible to keep them away from your tomatoes.

Before planting tomato seedlings on permanent place, it is recommended to treat it with Aktara, Confidor or Mospilan. A week after planting (every 7-10 days, if you have a risk zone), spray the plantings and the surrounding area with Fufanon, Bi-58, Actellik, Citkor, Fastak, Decis, Arrivo, Fury, etc.

Preventatively, twice every 8-12 days, in the second half of June - the first half of July, spray the plantings with Farmayod.

If signs of stolbur appear, it is necessary to spray ALL tomatoes twice (with a difference of 8 - 12 days) with the bactericide Fitoplasmin. 4 days after using Phytoplasmin, it is advisable to apply it under the root bacterial preparation Extrasol, in order to restore the soil microfauna suppressed by the bactericide.

Tomato plants that show signs of stolbur need to be destroyed, since they can no longer be harvested and, in addition, they become dangerous for neighboring plants - the disease is transmitted from a diseased plant to a healthy one very quickly.

At my dacha I grow popular amateur varieties of tomatoes. This season, the plants produced fruits that were normally colored with outside, but on the cut with whitish and green spots. The pulp is very hard and tasteless. What happened?

A. Doronova, Nizhny Novgorod region.

This year, many gardeners faced a similar problem. Fruits of this quality have already been dubbed “wooden tomatoes.”

Judging by the description, the cause of fruit damage may be a dangerous mycoplasma disease of tomatoes - stolbur. Previously, it was noted only in the southern regions, but now the pathogen has penetrated into the center of Russia. The disease affects all members of the nightshade family, destroying from 20% to 100% of plants. Strong development of the disease is observed during periods with high temperatures, and this summer has been hot, at least in the Nizhny Novgorod region.

HOW TO IDENTIFY THE DISEASE

The symptoms of stolbur are very diverse and manifest themselves differently in the plant (either all at once, or only some). Signs of stolbur may appear at the flowering stage, but not everyone knows that this is how the disease begins.

Most characteristic feature diseases - greening or growth of flowers. The petals either do not develop at all, or decrease in size and turn green. The sepals grow and grow together along their entire length, resulting in a flower shaped like a bell. The pistil of such flowers is ugly, sometimes it becomes very large and gradually grows into a shoot. Diseased flowers remain sterile.

A specialist can determine the disease by the leaves. The leaves, especially the upper ones, have an anthocyanin tint and are often folded into boats; the purple color of the veins is noticeable on the underside of the leaves. The leaves of the lower tiers are yellowish in color. Leaf blades and stems become rough and brittle.

Also, in the columnar bush, the shoots extend at a more acute angle, the bush resembles a broom. But sometimes only top part the plant has a changed appearance. This is due to the stage at which the infection occurred.

If the plant picks up an infection during the formation of fruits, then they are colored unevenly, their color is not red, but yellow-orange or white-pink. A mesh may appear on the underside of the fruit, which can be seen through the skin. Or the skin at the bottom dries out and resembles parchment paper.

In such fruits, the cells of the vascular-fibrous bundles are highly developed, and the seed chambers are reduced in size. The seeds are either puny or absent. The flesh of the fruit is hard and has a poor taste, hence the name “wood tomatoes.”

Similar fruits can be found not only in tomatoes, but also in other nightshades. This year, for example, hard fruits have grown in eggplants. The color of the skin was lighter, with a brownish tint. The pulp is also not juicy and woody.

WHERE IS THE DANGER?

From the notes of specialist phytopathologist N. Korganova: “Stolbur is caused by mycoplasmas, which, with their size and ability to penetrate living organisms, are close to viruses, since they do not have hard cell membranes, and by “lifestyle” - to gram-negative bacteria. Therefore, stolbur is often confused with either a viral or a bacterial infection."

The causative agent of the disease overwinters on perennial weeds (field bindweed, field thistle, garden thistle, common chicory, alfalfa). The infection is carried by insect pests, in particular leafhoppers (in our case, perhaps also aphids and whiteflies).

Since clogged areas are populated by cicadas 2-3 times more intensely than clean beds, an outbreak of stolbur usually occurs when the number of weeds, especially field bindweed, increases sharply.

Pillar weeds have a characteristic appearance - the entire plant is chlorotic (pale, light yellow), the leaves are small, the plants look dwarf, and lag behind others in development.

The incubation period (from the moment of infection to the appearance of symptoms) lasts 1-1.5 months. However, on weakened specimens (with a lack of water, nutrients, in dense plantings), the disease is more transient. Fungal and bacterial infections also accelerate the development of stolbur.

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Symptoms of the disease

When exposed to the pathogen, leaf segments decrease in size and acquire a chlorotic color with a purple or pinkish tint. The corolla petals and sepals may be enlarged. Sometimes they grow together or are reduced. The edges of the petals have a characteristic purple tint.

Internal organs flowers are modified: the pistils are shortened, the stamens are underdeveloped, the petals become discolored or become partially green.

The fruits are deformed, harden, and white vascular tissue appears on the cut, increased in size.

The roots are covered with numerous cracks, the bark turns brown, and strong lignification is observed in the internal tissues of the roots.

A characteristic symptom of stolbur is lignification of stems and fruits (sclerosis). In an infected plant, rings of wood and thick-walled bast form early. In diseased fruits, few seeds are formed, the vascular-fibrous bundles are hypertrophied, the vessels themselves are porous, some are lignified.

Some symptoms of stolbur are similar to phosphorus deficiency and some viral diseases of tomato (pepino mosaic, yellow curly top, aspermia).

Morphology

The causative agent of the disease is Solanaceae phytoplasma. Phytoplasma bodies have a spherical or oval shape. These are unicellular, nuclear-free organisms without a cell wall, living in intercellular spaces and in plant cells.

To accurately diagnose the disease, it is recommended to use the grafting method or the method of mechanical inoculation of juice. Tobacco is often used as an indicator plant ( N. tabacum). 30 days after infection on the indicator plant, the leaves become fragile, the inflorescences take the form of panicles. Flowers do not produce petals. Pistil proliferation is sometimes observed.

Biology

The tomato pillar is similar to viruses not only due to the similarity of visual symptoms, but also to the persistent method of transmission of the infectious principle.

It is likely that the increased formation of lignin as a result of the pathological process is associated with the transformations of phenols involved in respiration.

This infection is a typical natural focal disease with stable circulation of the pathogen in nature. Phytoplasma is reserved by perennial weeds.

The spread of infection between plants is carried out by sucking insects. The main persistent vectors are leafhoppers, in particular Mlokosevich's leafhopper ( Hyalesthes mlokosieviczi), clover aphrodes ( Aphrodes bicinctus).

These and other types of leafhoppers are capable of carrying pathogens for 2.5 months. Peak numbers of vectors are observed in mid-July. In this regard, the intensive development of the disease occurs in the second half of August. Insects overwinter on the roots of various weeds and perennials. cultivated plants. They prefer field bindweed.

The incubation period lasts 30 days. The infection is not transmitted by seeds. Phytoplasma affects various vegetable crops(eggplant, peppers, grapes, potatoes), as well as weeds black nightshade, field bindweed and others.

Phytophthora of tomatoes (brown rot). Brown rot is a fungal infection. When falling out large quantity precipitation during the growing season of plants, it can ruin the entire crop. This is one of the most dangerous fungi that attacks the fruits, stems, and leaves of tomatoes, completely paralyzing the life and growth of plants.

Phytophthora of tomatoes (tomatoes).

Fruits affected by late blight rot before they have time to turn red. The infection spreads to tomatoes from plantings. The first symptoms of infection are the appearance brown spots on leaf blades tomatoes and light white plaque on the underside of leaves in wet weather. From the leaves, the disease spreads to the fruits, which also become covered with brown spots, then harden, and then soften, acquiring a brown color. The inflorescences also darken. The flower stalks dry up.
Fruits that managed to grow and ripen before the plants became sick are still affected by late blight when stored next to diseased fruits.
On a note: Its activity increases sharply under the influence of fog, heavy dew and sudden temperature fluctuations.

Phytophthora of tomatoes (prmidora). Control measures

To prevent brown rot disease of tomatoes, you should choose highlands for planting, excluding lowlands and waterlogged soils. The power supply area should be increased to accelerated distillation For seedlings, use peat-humus pots. Plants need to be fed by increasing their dose when planting tomatoes; when planting early, use it to add to the holes.

These measures will not completely destroy late blight, but will significantly weaken its activity. Good results provides a selection of phytoresistant tomato varieties. In addition, you should not plant tomatoes next to potatoes.

Before planting, the seeds should be kept for 20 minutes in a 1% solution of potassium permanganate, then they should be washed well in clean water and dry.

During the period of growing seedlings, it is necessary to spray the tomatoes with a 1% solution of Bordeaux mixture, repeat spraying should be done after 2 weeks, and so on up to 4-5 times during the entire growing season. The last spraying should be carried out 8 days before harvesting.

Early harvesting of fruits in an area with diseased plants, followed by heat treatment them at a temperature of 60°C for 2 minutes will also help rid unripe fruits of late blight. Green tomatoes are processed at more low temperatures(40-45° C), but they should be kept for up to 4 hours. Diseased fruits are discarded, and plant residues after harvesting tomatoes are completely destroyed.

For your information: Late blight is successfully suppressed by treating plants with potassium permanganate and garlic. To do this, take 1.5 g of potassium permanganate and 1.5 cups of well-ground garlic pulp per 10 liters of water. Spraying is carried out half a month after planting seedlings in open ground. Spray again after 10 days. After this, you should water the plants with the solution potassium chloride(30 g per 10 liters of water) with 40 drops of iodine added to the solution. 500 ml of liquid is poured under each plant.

The effectiveness of potassium is significantly enhanced if water-soluble phosphorus fertilizers are added to the fertilizing solution or applied to the soil.

Material prepared by: horticulture specialist Buinovsky O.I.

Stolbur can affect not only tomatoes, but also eggplants, potatoes and peppers, as well as many weeds. Stolbur also has another name - phytoplasmosis. Standard varieties are less susceptible to this scourge. And the losses of tomatoes will be especially large if they are damaged on early stages. Maliciousness of this disease consists in a reduction in yield and deterioration in the commercial qualities of tomatoes.

A few words about the disease

Flower clusters begin to grow upward. At the same time, the petals of the flowers turn green and become smaller, and the calyxes grow together, becoming like bells. Plant flowers often become sterile.

Lignified tomato fruits are characterized by uneven color. Their flesh quickly becomes whitish, hard and tasteless, and on cuts one can see highly developed white vascular tissue.

The causative agent of stolbur is phytoplasma. It overwinters in the rhizomes of affected perennials and weeds; its overwintering is especially often observed on crops such as elderberry, St. John's wort, plantain, thistle, bindweed and a number of others.

The spread of the harmful virus occurs mainly by leafhoppers. By feeding on infected weeds for two to seven days in the spring, they become capable of transmitting the infection to surrounding tomatoes.

How to fight

Growing tomato seedlings should be taken as responsibly as possible. During the growing process, it is recommended to treat it twice with Mospilan, Confidor or Aktara. First, the treatment is carried out 25 - 30 days after sowing the seedlings, and then immediately before planting in a permanent place. And it is useful to treat the soil a week before planting seedlings with a selective herbicide called “Stomp”. Watering growing crops should be regular. After them, it is recommended to thoroughly loosen the soil.

Growing tomatoes can be sprayed with insecticides such as Karate Zeon and Aktara. They do an excellent job of killing leafhoppers when they begin to appear in the open ground. And in seedling greenhouses, it is recommended to treat crops with these means before planting them in the ground. Fury, Arrivo, Decis, Fastak, Tsitkor, Actellik and Fufanon are also excellent in the fight against leafhoppers. And to limit the spread of these pests, various canopy crops (for example, sunflower or corn) are often sown around the plots.

IN for preventive purposes It is recommended to treat the areas with Farmayod twice with an interval of eight to twelve days. It is best to do this in the second half of June and in July, in the first half of the month.

If approximately 20–30% of the vegetation is affected by the disease, then twice, also at an interval of 8–12 days, the tomatoes are sprayed with a bactericide called “Phytoplasmin.” And four days after using this drug, it is recommended to apply “Extrasol”, a bacterial preparation that helps restore the soil microflora suppressed by the bactericide, under the roots of the plants.