Gray rot on the ground. How to deal with gray mold. Effective methods of agricultural technology in the fight against gray rot

Rot - a group of diseases that are manifested by browning and decay of individual parts or the whole plant. They are caused mainly by fungi, but bacterial rot, or bacterioses, also appear. Conventionally, rot can be divided into rot of the root system, trunks and branches, leaves, berries and fruits.

ROOT ROT

There is browning and decay of the lateral and central roots of plants.

They are most often caused by pathogenic microorganisms that persist on plant residues in the soil.

Soil pathogens include fungi that cause rots such as fusarium, verticillium, white sclerotal, gray, late blight, as well as bacteria that cause bacterial rot.

The infection penetrates the root system through mechanical damage, damage by soil pests and with planting material grown from rotted cuttings and seeds.

1. Fusarium and verticillium rot dangerous because the mycelium of the fungus-causative agent penetrates into the vascular system, fills it, and from the roots moves up the stem to the leaves and flowers. In herbaceous plants, such as strawberries, fusarium (photo 1a) and verticillium (photo 16) rot cause rotting of the root system and browning and death of the aerial part of the bushes.

In woody shrubs (currants, gooseberries), the root system and vessels of the stems are affected, which is manifested by tracheomycosis wilt, when nutrients from the roots do not reach the growing shoots and leaves. In this case, the affected individual branches and whole plants suddenly wither and dry out. On the affected roots, sections of cuts, sections of the central veins of the leaves, a whitish coating of mycelium of the fungus develops.

2. Late blight rot Recently, it has been constantly found on strawberries and is distributed with imported planting material. Affected bushes wither (photo 2a), black spots appear on the leaves (photo 26), petioles and growth points gradually turn black. A dense dark mycelium develops on the affected tissues, which can be seen even after overwintering (photo 2c).

3. Gray rot affects growth points, growing stems, leaves, fruits (photo For) strawberries. In some years, entire plantations of this crop die from the spread of gray rot.

After the snow melts, the plants have a characteristic appearance (photo 36), black sclerotia are visible - the fruiting bodies of the fungus. With thickened plantings, bushes of currants, gooseberries, wild roses and roses also suffer greatly from gray rot.

The causative agents of all these rots are low-temperature pathogens, they actively develop under the snow cover when the plants are at rest.

From this in the spring we observe that the leaves on the strawberry bushes are all brown, dry, and in some places fruiting bodies have already been formed on them - sclerotia (photo 36), in which the fungus remains for many years. Tree and shrub seedlings are most affected by root rot in nurseries, in thickened plantings, when a high background of soil infection is observed in the soil.

4. Peripheral wood rot, or butt rot(butt - the lower extended end of the tree trunk). It is caused by the fungus mushroom (photo 4). Under the bark of the roots and the base of the trunks, it forms a grid of black flat rhizomorph cords, with the help of which it actively spreads from plant to plant. The appearance of fruiting bodies of everyone's favorite edible mushroom in the garden is a symptom of big problems for woody plants.

STEM ROT

5. Rots caused by tinder fungus.

The appearance of tinder fungi of various shapes, sizes, and colors of leathery fruiting bodies is a sign of damage to tree wood by rot (photo 5).

6. non-infectious rot. When pruning trees, when carrying out phytosanitary cleaning of dried and broken branches and skeletal branches, stumps and saw cuts often remain unpainted with paint. Bare wood dries up, cracks, dies off, under the influence of rain and snow begins to rot, the wood is destroyed without the participation of a fungal infection (photo 6).

7. Gray rot. Often affects unripened shoots of weakened shrubs after overwintering (photo 7a). An example is young bushes of currants, raspberries, wild roses, grape stalks (photo 76).

8. penicillium rot. Penicillium rot is also common on grape stems (photo 8). Sporulation develops as bluish-green or olive-colored pads. Spores quickly re-infect neighboring berries and young shoots.

9. shrinkage(photo 9) of trunks and skeletal branches often causes bacterial necrosis of the bark, or bacterial cancer, in which the wood of boles and branches rots and a sharp sour smell of fermentation appears.

10. Takes a special place monilial stone burn, which manifests itself in some years not only by the drying of skeletal branches, but often leads to the rapid death of entire trees. The spread of the disease begins in the spring with browning and drying of flowers, ovaries, fruit twigs, young leaves also turn brown, which do not fall off for a long time (photo 10). A grayish coating of mycelium develops on the affected bark and leaves.

LEAF ROT

11. Gray rot. It appears on the leaves as brown zonal spots, the necrotic tissues of which crack and fall out in hot weather, and at high humidity a smoky-gray mycelium of the fungus forms on them.

They are caused by the fungus that causes widespread gray rot (photo 11a - browning and drying of currant leaves affected by gray rot; photo 11b - gray rot of a grape leaf; photo Non-gray rot of berries and raspberry leaves).

ROTT OF BERRIES AND FRUITS

They can be caused by both gray rot, penicillinous rot, and monilial rot.

12. Monilial rot also called fruit rot. It affects almost all crops and the pathogen fungus is the same for all (photo 12a - the beginning of the appearance of apricot fruit rot; photo 12b - hazel fruit rot; 12c - quince fruit rot; 12d - apple tree fruit rot). On the surface of decaying berries and fruits, numerous light-brown sporulation pads develop, located in concentric circles (photo 12d). The infection persists in affected or mummified berries and fruits (photo 12e), as well as in the tissues of one-year-old shoots with mycelium.

13. Black is widespread on strawberries. berry rot, or rhizopus, which manifests itself in hot weather with high humidity on overripe berries (photo 13).

HOW TO FIGHT ROT - CONTROL MEASURES

1. Use of healthy planting material, compliance with all the requirements of agricultural technology, timely culling of affected plants with a clod of earth, collection and disposal of mummified fruits and carrion.

2. In industrial cultivation against root rot, preventive and eradicating sprayings are carried out with the systemic fungicide Fundazol at a concentration of 0.2% (20 g per 10 l of water).

3. Against gray rot on strawberries during the budding period, spraying with bacterial preparations Alirin-B, Planriz is carried out. At the beginning of tying berries, bushes can be dusted with fluffy lime (15-20 g per bush).

4. Against late blight rot, honey agaric fungus, stem rot and fruit rot, preventive spraying is carried out with a 1% Bordeaux mixture or its substitutes (HOM, Abiga-Peak) when buds open and immediately after flowering crops. With a strong spread of diseases, spraying is repeated in the fall, after harvesting, with the same preparations.

Rot and types of rot - photo

Photo and text - phytopathologist L. TREYVAS

It is very important to recognize in time that it is gray rot that threatens tomatoes, cucumbers, grapes, strawberries and immediately begin agrotechnical rescue measures.

The clinical picture of the manifestation of gray rot

Most often, infection occurs due to uncleaned plant residues that are on the ground, in the soil. Infection occurs through dead tissue of plants, especially if the weather is wet.

Such conditions exist in protected ground. Therefore, crops growing there are affected more often than similar ones in open ground. During the disease leaves, flowers, stems, fruits are affected. Usually, the disease first manifests itself on the lower old leaves, then spreads to the stem. Dry spots of light brown color appear here.

When the spores of the fungus reach the fruit, they first infect the stalks, then a gray spot forms, which grows rapidly and soon covers the entire fruit. It becomes watery with a gray fluff - this is what conidial spores make themselves felt.

What crops are threatened by gray rot?

It can infect many types of plants, causing great damage:

• strawberry;
• grapes;
• cabbage;
• buckwheat;
• gladioli;
• peonies.

Kagan fruit rot threatens pumpkin and sugar beets.

This disease is the only one that accompanies the bush throughout the year, if conditions are favorable for this disease. The harmful microorganism is especially dangerous during vaccinations, as it affects not only the harvested cuttings, but also the vaccination site. It can settle both on one-year-old wood and on the green parts of the vine.

If damp cold weather is in the spring, gray rot often covers young shoots with its bloom, buds blooming, as a result of which they may die. This fungus is dangerous for ridges and berries. Gray rot becomes the causative agent of vinegar rot if it appeared during the period when the berries were not yet ripe. It is easy to recognize the disease on the fruits, when they are affected, they first turn gray-brown in color, in wet weather a gray coating appears on them. In this case, the bunch can turn into an unattractive lump. If dry weather is established, then the development of the disease stops, and the affected berries shrivel.

If you notice any of these signs on the vine, you need to act immediately, but it is better to take preventive measures even before that. First of all, agrotechnical.

It is necessary to form a high stem of the bush, provide it with a sufficient area of ​​\u200b\u200bnutrition, and fight weeds. Do not apply large doses of nitrogen fertilizers, which lead to the formation of unstable, succulent tissues susceptible to the fungus. It is advisable to start removing grape leaves located below the clusters in early September. Since at this time they are no longer needed to feed the berries, but contribute to the spread of fungal and other infections.

Previously, the bushes were sprayed with soap, but then it was found that even its high concentration does not help fight gray rot. The resistance to the disease with the use of Bordeaux liquid is quite successful, but this remedy affects the quality of the berries, so it is better to refuse to use it and spray the bushes with it only in early spring and late autumn after harvest. Also, preparations of the benzimidazole group were successfully used earlier, but the strains of gray rot that appeared soon showed their resistance to them. Moreover, having adapted to these drugs, they found useful substances in them and from this they began to develop even more strongly.
Gray rot of grapes is defeated with the help of Ronilan and Rovral. The first must be diluted at a concentration of 0.1%, and the second at 0.075%. Against this disease, the Teldor fungicide is used. A preparation diluted according to the instructions is used for 1-3 sprays. The last time - 4 days before harvest. Against gray rot of grapes and some other crops, drugs can be used:

• "Euparen";
• "Mikal";
• "Byleton";
• "Ridomil Gold MC";
• "Folpan";
• "Topsin M";
• "Folpan".

Its development and spread is facilitated by a lack and excess of moisture, overfeeding with nitrogen, evening watering, as well as watering with cold water, a lack of important trace elements, and sudden changes in temperature. If cold weather sets in, the first signs of damage can usually be seen at the attachment points of the flowers to the stem. Insects carry not only pollen from flower to flower, but also spores of the fungus, thus contributing to its spread.

In order to prevent the appearance and development of this and other cucumber diseases, it is necessary to observe crop rotation, remove plant residues in time. It is better to water in the morning and always with warm water, and then greenhouses and greenhouses need to be ventilated.

If you find signs of gray rot on the lower leaves, then cut them off. If they appear on the stems, these areas must be sprinkled with copper-chalk powder or lime. With severe damage to the stems, these places are carefully cut out, and then they are treated with these preparations. You can dilute copper sulfate with water to a concentration of 0.5%, let the cut points dry, and then wipe them with this solution or sprinkle with crushed coal. Flowers affected by gray rot are best removed.

In order for the plant to be able to resist the disease, make foliar top dressing. To do this, in 5 liters of water you need to add 1 g of copper sulfate, 0.5 g of zinc sulfate, 5 g of urea. Infected stalks are smeared with an aqueous solution of the Rovral preparation and a chalk mixture in a 1: 1 ratio. For the prevention and control of gray rot on cucumbers, it is recommended to use the drug "Trichodermin". "Euparen multi" has also proven itself well. They are treated every 2 weeks.

Gray rot of tomatoes

It is easy to recognize, it appears as light brown spots that first affect the lower leaves, then spread higher. On the stem, these spots can be both small and large. Gray rot on mature fruits starts from the stalk. If you do not notice a small gray spot in time, it will quickly spread throughout the fetus and destroy it. On young fruits, botrytic spotting may also appear in the form of small spots with a white border.

In addition to removing affected plants, observing crop rotation, spraying damaged stems with Trichodermin can be advised. Gamair will also help from gray rot. To do this, dilute 1 tablet in 1-1.5 liters of water. Tomatoes should be sprayed at the beginning of budding and fruit formation, with an interval of 1-2 weeks. This drug will also help defeat phytophthora. Fitolavin also proved itself well from gray rot. 20 milliliters of this drug is diluted in 10 liters of water and the plants are sprayed 1-2 times with an interval of 7-10 days, 10 liters of the solution is enough for 100 meters of planting. In addition to tomatoes, you can process "Fitolavin" and cucumbers.

It can lead to the death of a large part of the crop. Therefore, before planting strawberries, the prepared bed is covered with black cellophane, round holes are made in it with scissors and young bushes are planted. For prevention, you can spray them before flowering with Fitosporin or another drug that helps prevent gray rot.

When planting, the bushes do not need to be placed too often - you need to provide them with ventilation. If the berries do not touch the ground, then the harmful effects of the disease are reduced significantly. You can put planks under the berries, put sticks to the flower stalks, tie them to them. Straw, sunflower husks, sawdust are placed under the bushes. This will also protect the berries from contact with the soil.

After the end of fruiting, you need to spray the bushes with Bordeaux liquid, diluting 2 teaspoons of this drug in one liter of water. The drug "Zircon" is useful for plants, it will help strengthen the immune system, then it will be resistant to fungal diseases.

Fruits affected by gray rot must be collected and disposed of. For adherents of folk ways to fight diseases, we can recommend this recipe: once a week, spray strawberry bushes with mustard infusion. This must be done before flower stalks appear on the strawberries.

These simple preventive measures, the fight will help defeat gray rot on grapes, cucumbers, tomatoes, strawberries and other plants.

For more information about gray rot on cucumbers and how to deal with this disease, see this video:

Fungal disease - gray rot affects not only the berries, but also the bush. During rainy and wet weather, this disease can destroy most of the crop. The spores of the fungus that cause this type of disease are in the ground and are not afraid of low temperatures and drought.

The first sign of the appearance of this disease is the appearance on the berries dark, slightly sunken spots.

In place of the spot, the tissue of the fetus softens and becomes sluggish and watery. The fruit loses its inherent aroma, characteristic color and taste. In a short period of time, the spots spread, and a gray coating appears on them.

The first sign of the disease is the appearance of dark depressed spots on the fruits.

The berries rot and thereby spread spores, infecting nearby healthy bushes in the garden. This disease can appear not only during the fruiting period, but also during the flowering period, affecting the flowers. This disease is most dangerous during storage.

In an unventilated, humid room with a high temperature, gray rot spreads very quickly and infects the fruit.

Causes of rot and how the fungus spreads

Spores of a fungal infection are constantly in the air and soil, but the following conditions are necessary for the spread of this disease:

1. Wrong site selection for landing. A bed for growing strawberries should be lit by direct sunlight and well ventilated. On poorly ventilated beds, the spores of this disease develop quite rapidly;
2. Too thick landing. Growing, strawberry bushes form a shadow, why the ground under them is enough and does not warm up, and also there is not enough air access. In this case, to eliminate this problem, strawberries must be planted;
3. Excessive humidity. During the period of rains or heavy watering, increased humidity is formed, which is the cause of the spread of the fungus. Loosening the soil and covering strawberry beds during frequent rains will help avoid infection;
4. A large number of weed grass. The presence of a large number of weeds in the garden limits the access of fresh air and prevents good blowing of the beds. It is necessary to timely weed the beds;
5. Mechanical damage. Fruits damaged mechanically, as well as by slugs and insects, very quickly become infected with this type of fungus.

Ways to deal with gray mold

There are a number of activities and methods to deal with gray mold:

1. Collection of infected fruits and their disposal.The fruits are carefully picked and buried far from the place of growth. It is impossible to throw away infected berries. The spores of the fungus are carried by the wind and infect healthy plants.
2. With a strong thickening of the plants, it is necessary to remove excess leaves and thin out the frequency of bushes. The introduction of ash into the soil under the bushes and pollination of plants. Temporarily stop watering until the topsoil is dry.
3. Feed the bushes with the following solution:
   • water - 10 liters;
   • potassium permanganate - 2 grams;
   • boric acid - 2 grams;
   • iodine - 20 drops.

   When processing, it is necessary to touch the lower surface of the leaves.

4. Necessarily prevent fruit from touching the ground. To do this, you can do mulching with straw or pine needles, tie bushes using special frames for this purpose.

Fighting gray mold with chemicals

Chemical treatment should be carried out in spring or summer, since the spores of the fungus do not die in frost and cannot be destroyed by digging the soil.

Processing needs to be done three times:

• as soon as the leaves begin to grow;
• after tying the buds;
• after the entire crop has been harvested.

• at temperatures above +3 degrees, it reaches its greatest efficiency until high temperatures are established. With the onset of heat, the activity of the drug increases, but the period of action is significantly reduced. Therefore, processing must be carried out at the very beginning of the season.
• used to protect berries during transportation and storage. Upon contact with the surface, the drug forms a thin film that protects against penetration into the tissues of the infectious agent.
• prevents the appearance and spread of fungi, suppressing their activity. Promotes better storage of fruits.

The use of folk remedies

To combat gray rot, effective folk remedies are:

• Iodine solution. Dilute 10 drops of iodine in 10 liters of water and spray when a disease is detected and as a preventive measure. Spraying is carried out 1 time in 7 days.
• mustard solution. In 5 liters of hot (not boiling) water, dilute 50 grams of dry mustard powder. Insist for two days, strain, dilute with water in a ratio of 1: 1 and process strawberries with this solution in the spring.

Preventive actions

Preventive measures to prevent the disease include:

• Timely removal of weeds on the beds;
• tillage ash or lime;
• Bush processing Bordeaux mixture;
• Removing foliage from bushes after harvest. It is necessary to carry out the removal in advance so that new leaves grow on the bushes before the onset of frost;
• Change the location of strawberries every three years;
• Do not leave ripe berries on the bushes;
• Remove diseased berries immediately from the bushes and dig them in;
• Mulch beds with pine needles or dry straw.

To protect strawberries from the appearance of gray rot, experts advise:

• remove the mulch left over from last year and dry foliage, as gray rot spores remain in them;
• timely fertilization of strawberries helps to strengthen the bushes and disinfect the soil;
• it is not recommended to fertilize with mullein, since it is a favorable environment for the reproduction of the fungus;
• do not use nitrogen-based fertilizers, as this contributes to the excessive growth of the bushes. Growing bushes form a shadow, which prevents the full heating and ventilation of the soil;
• after every watering loosen the soil to prevent stagnation of moisture conducive to the development of the fungus;
• can help prevent disease planting onion or garlic between rows of strawberries. Their biologically active substances inhibit the development of the fungus;
• before flowering, it is imperative to treat strawberries with special preparations for a fungal infection.

In order to protect strawberries from gray mold infection, it is necessary to create the right conditions - well-heated and ventilated beds. And patient and caring care will be rewarded with a good harvest of ripe and healthy berries.

If your vegetable crops are covered with an unpleasant gray-brown coating, it is possible that it is time to sound the alarm. This sign may indicate one of the most unpleasant diseases - gray rot. Any self-respecting gardener makes every effort to prevent the appearance of such an uninvited guest on his site, because getting rid of gray rot is not at all easy.

The main source of gray rot is contaminated soil. In addition, previously affected plants can become a source of the spread of the disease. Contributes to the development of gray rot and an increase in the level of humidity, coupled with a decrease in temperature.

Despite the seriousness of the disease, fortunately, it is quite easy to detect in the earliest stages of the onset. In addition, careful and, most importantly, proper care is one of the leading factors preventing its occurrence and development.

At the slightest sign of the appearance of a plaque that has a grayish tint on the stems or foliage of plants, it is worth immediately checking all plantings. By the way, gardeners also call such a raid snowy. If there is no reaction on your part to the appearance of plaque, after a certain time the affected areas acquire a light brown or even reddish brown hue. If at the same time it is damp and cool outside, the mycelium will cover such spots in a matter of days, simultaneously infecting all plants planted nearby. Remember that the mycelium of the fungus contains a huge amount of spores. Over time, plaque acquires a strong resemblance to ash, after which the plant dies.

How to prevent the manifestations of gray rot?

First of all, refuse to thicken when planting. So you exclude the accumulation of a large amount of moisture in the soil in your area. In addition, when watering, be as careful as possible: drops falling on the foliage of plants can also activate fungal spores. Some care must also be taken when fertilizing, especially if you are using highly concentrated preparations. They should not fall on the stems and leaves of plants. Almost every fertilizer contains nitrogen, which, when it gets on plant tissues, softens them. This leads to a decrease in the plant's resistance to diseases and pests.

It is advisable to use mainly phosphorus and potassium fertilizers in your area. Before planting, make sure that the planting material is of really high quality. This is especially important when using personally collected seeds or bulbs. In any case, planting material needs preliminary disinfection before planting.

If gray rot, despite all your efforts, still hit the plants on the site, immediately treat them with a soapy copper solution. Works well against this disease and 1% boric acid. Gardeners and gardeners also achieve good results by applying a paste on the affected areas, which includes glue and trichodermin. All of the above measures will work only at the initial stage of the disease. By the way, the fungus that causes gray rot does not like the smell of mustard, calendula and marigolds. So planting them on the site is also considered a preventive measure. These plants are unpretentious in care, so there is only benefit from them on the site.

Fungal diseases on orchid leaves

Orchid diseases are a fairly common phenomenon. Most often, representatives of the orchid family suffer from various rot and fungal diseases. But they are also susceptible to viral diseases. The most common orchid diseases and their treatment are described in detail below.

One of the most dangerous and common fungal diseases. The first signs of the disease appear within 12 hours from the moment of infection. Young shoots are the first to suffer. They become black and covered with a slimy coating. Black rot most often affects such types of orchids as, and.

Causes of occurrence:

• Constant overheating of the roots.
• High ambient humidity level.
• Too dense substrate.
• An excess of nitrogen.

Preventive measures:

• Compliance.
• Airing.
• Use specialized for orchids.
• Regular processing from .

Treatment

The first thing to do when black rot is found is to isolate diseased plants from healthy ones. The harmful fungus is easily transmitted by contact, so it is rather difficult to treat fungal diseases of orchids. To exclude further infection of healthy tissues, the entire cutting tool must be calcined or treated with alcohol.

Causes of occurrence:

• Abundant watering
• Low air temperature
• Wrong soil used when planting

Prevention and treatment

The best prevention of occurrence is the use of a specialized high-quality for planting. And also the plant must be looked after accordingly and strictly observed.

Treatment of the roots of the affected plant begins with their disinfection in a fungicide solution and the removal of rotten areas. The substrate is also processed. To do this, use Fundazol powder or Topsin. Treat the plant at least 3 times with an interval of two weeks. For the most complete disinfection, the plant pot is simply immersed in a fungicide solution for 10 minutes.

Root rot in Paphiopedilium

Fusarium rot

Gray rot, manifestations of signs of disease on orchid flowers.

Leaf spot of bacterial origin

Phalaenopsis orchid diseases can also manifest themselves in the form of various leaf lesions. For example, if the irrigation regime is not observed and the air temperature is high, bacterial spotting begins to spread on the plants.

First, the affected leaf blades begin to turn yellow, then they darken, become soft, and cracks begin to appear on their surface. The most characteristic sign of bacterial leaf spot is wet black spots on the surface of the leaf blades.

Treatment

To treat an infected plant, all spots on the leaves of the phalaenopsis orchid are cut out with a pre-disinfected sharp instrument. After that, the wound surface is treated with charcoal powder or an alcohol solution of iodine.

In cases where dark spots have occupied almost the entire surface of the leaf or damage has already affected the central vein, undiluted Fitolavin is used for processing. It has the ability to persist in tissues for a long time. If within 2 weeks after the treatments there are no signs of the disease, it is considered that the plant has fully recovered.

Bacterial spots on orchid leaves

Anthracnose

Problems with orchid leaves also occur with anthracnose. Its characteristic feature is small dots on the leaves, which later increase in size, turning into spots, after which they merge. The places of such mergers acquire a black color and become, as it were, depressed. At the last stage of the development of the disease, yellow spots appear.

Causes of occurrence:

• High air humidity
• Stagnation of water in the axils of the leaves
• Poorly ventilated area

Prevention and treatment