Bacterial Burn (Erwinia amylovora)
I first encountered this disease about seven years ago, when I acquired cuttings of new pear varieties at the TSHA and planted it in my garden. Part of the crown hawthorn. Part of the stock - two-year cotoneaster. The varieties in the crown were higher above the ground, they saw more sun and aired better. The gains were small no more than 20 cm, so none of them got sick. And the graft on the cotoneaster was planted among the old trees in the garden on well-fertilized soil, so the next year gave growth to half a meter. A year later, I saw strange burns on most of these young pears. In June, the tip of the shoots looked as if it was scalded with boiling water. The leaves and thin ends of the shoots are blackened and withered. By the autumn, some of them gave a small wave of growth from the lateral buds, but in the coming severe winters almost all of these new varieties had been frozen out by me.
At first, I thought that these were the usual fungal lesions such as powdery mildew. I thought that the new varieties turned out to be not resistant to it and it would be necessary to carry out spring treatments with copper preparations. But then I looked more closely at the photos of the diseases of pears caused by fungi and realized that I had something new. And so I learned that in my garden I brought not a fungal infection, but a bacterial infection - a bacterial burn.
When I began to discuss this problem on the PX forum, I learned that this disease is found in many gardeners. But no one really knows how to diagnose and treat it. And there are a lot of myths and judgments about it and even more recommendations.
I looked at the available literature. Everywhere there is only one recommendation, to cut, uproot and burn the affected plants. Occasionally there were tips to treat with copper-containing preparations. Looked at foreign literature. There are other tips. This disease has been discovered and studied since the 1980s – 1990s. well known. And they treat it like any infection, especially with modern antibiotics.
Bacterial fruit burn is a quarantine disease, it is widespread in Canada, USA, New Zealand, Australia, Japan, Western European countries, in recent years it has appeared in the western regions of Ukraine and Lithuania.
It is among the most dangerous diseases, it develops on more than 170 cultivated and wild plants, most of which belong to the Rosaceae family. Flowers, leaves, shoots, branches, stem, roots, fruits are affected. Usually, the first signs can be found in the spring on single or all flowers in the outlet. Affected flowers first wither, then dry quickly, acquiring a brown color, and most often remain on the tree until autumn. The disease spreads to the pedicel, which first becomes dark green, then turns black. From the infected flowers, the infection passes to the rosettes of leaves and young shoots, from where it can spread throughout the tree.
Causes disease Erwinia amylovora, gram-negative bacteria from the family Enterobacteriaceae. The natural reservoir of this disease is North America, from where it has spread to most of the rest of the world.
It caused the greatest damage to gardens in Australia and New Zealand. Then she began to rampage in Japan. A microbe was first discovered by Japanese scientists on pears grown in northern Japan. The Japanese authorities, however, hid this discovery for many years, denying the existence of a new disease, and the Japanese scientist who discovered it is believed to have committed suicide. After his name was leaked to the press, it became known to Japanese farmers, then the whole world.
The bacterium was brought to us along with southern saplings, which were completely uncontrolledly imported into the northern regions. And now our gardeners see the bacterial burn of fruit everywhere, above all, on a pear.
It is good that mature trees are too tough for him, only young plantations are sick.
Organic soil-rich, or nitrogen supplements only increase the burn. On poor soils, young pears are sick less and more quickly cope with a burn.
Honeybees and other insects, birds, rain and wind spread microbes over long distances and infect plants through minor damage to tissues made by sucking pests and hail.
After sedimentation, the bacterium enters the plant through wounds and causes leaf wrinkling. Then blackening and drying. This disease spreads most quickly in hot, humid June days and is at rest in the winter when the temperature drops. Infected plant tissue contains viable bacteria, however, a new infection occurs in the summer when exudate containing millions of new bacteria appears from cracks in the plant. The death of the whole plant occurs when a massive infection. When with juices the microbe reaches the roots, and even the roots turn black.
Erwinia amylovora is the same microbe from the Enterobacteriaceae family as Escherichia and Shigella, Salmonella and Yersinia. Cause digestive disorders in humans. Therefore, it also works well for drugs used in the treatment of diarrhea in humans.
What diseases of pears are found in our gardens, how do we treat them, and with what is this disease not to be confused? I will remind you.
Diseases of pear. Measures to combat them
Scab - pear mushroom disease. Brownish blotches appear on the leaves, then the leaves dry out and fall off. Control measures. Against a scab disease, plants are treated in the spring when blooming leaves (for 10 liters of water, dilute 1 ampoule of Horus or Skor) or Oxy (2 tablets per 10 liters of water).
Mealy dew - mushroom disease. It affects the buds, leaves, shoots, inflorescences. First, they are covered with a dirty white mealy coating, then the patina turns brown, and small black dots form on it. In the future, the leaves turn yellow and dry, the shoots stop growing, the inflorescences dry out and do not tie fruit. Control measures. In the spring when blooming leaves, pears are treated with the drug "Topaz" (1 ampoule per 10 liters of water).
Fruit Rot - Fungal disease. Brown spots appear on the fruits, these spots grow quickly and cover most of the fruit. In this case, the flesh becomes brown, inedible, the fruits fall, and some remain on the trees to winter. Control measures. Trees are treated in the spring when leaflets are dispensed with the drug "Skor" (1 ampoule per 10 liters of water). After flowering, treated with the drug "Chorus" (1 ampoule per 10 liters of water). The consumption rate of a solution of 1.5 liters per adult fruiting tree. Can be treated against the rot of the fruit drug "Fundazol" (40 g per 10 liters of water).
Cytosporosis - mushroom disease. Dark ulcers are formed on the bark, which quickly grow and become red-brown in color and the bark dies off, on the bark the hillocks are clearly visible, at the same time individual branches die or the tree dies completely. Frosts, drought, high soil moisture, and insufficient nutritional care contribute to the development of this disease. Control measures. Treating trees with various preparations, the drug “Hom” is more effective (in 10 l of water it is diluted up to 50g), the plant is sprayed in the early spring along swollen leaf buds. Spraying is done at a temperature not lower than + 15ºC.
What is written about bacterial burn in our reference books? Quote: Blackening branches. Shrinking wood. One of the most serious diseases is a bacterial burn of an apple and pear tree. More often this disease suffers pear. The first signs of the disease appear in early July. Annual growths begin to dry up on the trees, the leaves turn black, and the diseased tree gradually dies within two years. Control measures. Buy healthy planting material. To fight every year with pests, especially sucking and gnawing. They are usually carriers of viruses. When pruning a tree, rinse the inventory - pruner, knife, saw, etc., only then proceed to pruning or grafting another tree. Infection often occurs during vegetative reproduction. Often take different saplings, cuttings from neighbors, unaware of a terrible disease. Although bacterial diseases compared with fungal significantly less. Bacterial diseases can be identified:
1. on the death of tissues (bark, desiccation of branches),
2. due to wilting of plants in parts or as a whole (because the vascular system is affected),
3. for wet rot of fruit during storage.
The affected plants are burned, and the place is disinfected with solutions - copper sulphate or "Home" (copper chloride). At this landing site do not produce 1-2 years.
In western gardens, antibiotics streptomycin and terramycin are currently used quite successfully, and they do not see much effect from copper preparations.
I am a doctor by profession. I have a great experience of using antibiotics in my garden, I am not afraid of them, so I will give advice to those who want to use them. Start with streptomycin. It is in bottles of 500 thousand units. sold in pharmacies and very cheap. Dose - ampoule of 5 liters is enough to handle a dozen young trees. It is better to process in June, when shoots grow rapidly for prevention. Then after 2-3 weeks. And after heavy rain with hail and the onset of hot weather. During this period, I additionally use immunity stimulants to choose from: Immunocytophyte, Silk, Zircon. It is very good to use phytosporin (all according to the instructions). It is not necessary to use streptomycin for many years in a row, due to the danger of the appearance of mutants with antibiotic resistance. Therefore, after a year, you can take 2 tablets of any tetracycline from a veterinary pharmacy and also dissolve in 5 liters of water.
At the forum I was asked many questions, but is it dangerous to use antibiotics in my garden, because they are not officially allowed. Will we break the ecology? I answered about the following. Do not be afraid of antibiotics in your garden. I will explain why. Streptomycin is now practically not used by doctors, because in half a century of its use, "human" microbes have already developed resistance to it, and it continues to work on plants.
- I do not think that the forum users, after reading these notes, will begin to apply it. Therefore, for the global ecosystem all this will be unnoticed.
- The microbe produces resistance strictly to a specific antibiotic. So to penicillins cross-resistance in any case will not.
- There are billions of germs and fungi in the soil, and they all constantly produce antibiotics. Our body is used to it. It was not for nothing that in the tuberculosis departments earlier streptomycin was administered to patients by many millions of units (milligrams) in long courses, for months, and they survived. They are not blind and deaf. And those doses that you apply in the garden will be indistinguishable from your soil background. But the proposed alternative "chemical protection" for the most part is more toxic and allergenic, since it is artificially created, and not by nature.
Down with the spade, long live the wormwood!
After reading this article, once again you understand the value of the letters of simple summer residents compared to scientific articles of certified agronomists. Scientists will offer a bunch of ways to solve this or that problem, and one is wiser and more difficult. A smart summer resident will look around, will think and understand that everything can be solved much, much easier.
Hello everyone! I live in the Altai Republic, I own 11 acres of land. Under the garden and the garden given seven acres. And I want to tell you about this.
When I laid the garden, I bought three pear trees. Three years later, the disease appeared - a bacterial burn, but only on two pears, on the third it was not. (Why? Just below.) I was recommended to be treated with ashes - it did not help. Pears blackened, had to cut off the tops of the shoots and cut off the leaves.
The trees were short and miserable. Then came an article about antibiotic treatments - purchased a vial of streptomycin, diluted in 5 liters of water. Last spring, and in the fall I sprayed twice a week. Pears went on the mend! This spring I repeated the procedure a couple of times, and this was the end of the treatment.
And now about what happened to the third pear. She did not get sick, although she was only 3 meters away from the diseased trees. She developed beautifully, had a good crown, clean leaves and was much higher than her fellows. The secret turned out to be simple: two bushes of wormwood grew near it.
When they appeared near the trunk, I wanted to remove them, but I left them and did it right. Wormwood grew one and a half meters tall, silver in color, beautiful. The trunk is thick, I cut it down in the fall with a hatchet, I did not take the cutter. So, the pollen and the smell of this wormwood played a role: the pear did not get sick.
By the way, the same wormwood grows between bushes of cherries and plums, and no bugs-bugs crawling through these bushes, never even the omnipresent ants!
I don't know where the wormwood came from. I think the seeds were blown by the wind. This spring I planted it near all my trees and shrubs: I want to believe that it will benefit them. After all, nature knows how to cure diseases without any antibiotics!
And the last. If you shift the sprigs of wormwood potatoes stored in the cellars, not a single tuber will spoil, and there will never be mice in the cellar. Tested on his experience, and he came to me from my parents.
Contrary to agricultural technology
And one more question regarding the agrotechnology of growing vegetables. They write a lot about it, probably, it is good and right. But I act contrary to all agrotechnical laws.
For several years I have been doing garden shovels. He dug the ground, made a bed, leveled, clapping from the sides. Then I got tired of it all. I got a tes, soaked it with an antiseptic, so as not to rot quickly, and shielded them all the beds. I bought humus, filled the beds, then dug along with the ground, and we got permanent, brown (from humus) beds.
Four five meters, where I have been planting onions for six years, and four four meters, where bows have been planted for the same number of years. Two four-meter beds for carrots next to an onion and one five-meter for beets. And I get a great harvest from these beds. And do not change the landing places. And for all the six years I have not observed any diseases. But the point, I think, is that after harvesting from the beds, I immediately sow the siderat — white mustard. I sow thickly with a green carpet.
Mustard is not only a good fertilizer, but also perfectly loosens the soil, treats it.
In the deep autumn I will crush it with a shovel, and in the spring I loosen the ridges with a pitchfork — I don’t need to dig, the earth is loose, I sprinkle with ashes and rake. And all the ridges are ready for landing. No more fertilizer, and so for six years.
I do the same in greenhouses. In the autumn I process them with tobacco, shag. I buy two packages of 200 g for each greenhouse, I pour it into an iron basin, I pour birch bark from above, first small birch chips, then bigger ones. I set fire to bark and leave the greenhouse, closing the doors and windows. A day later, I air and plant the siderats. I also cut them with a shovel just in the fall, loosen in the spring, sprinkle with ashes and level with a rake. Everything. The beds are waiting in the wings.
This is my agricultural technology: green mans, ash and good land.
How does the disease develop?
The rate of infection of a pear with a bacterial burn depends on the following factors:
• tree age (more often young saplings are affected),
• soil on the site (increased nitrogen content in the earth increases the development of a burn),
• climatic conditions (high humidity and air temperature - most favorable for the progression of the disease).
Primary infection occurs in spring during the flowering of the pear. Over long distances, bacteria from infected plants are transported by insects, birds, wind, and rainwater. Once on the flowers, the bacteria begin to actively proliferate and spread inside the plant, striking young shoots, branches, stem.
Infection can also occur through the damaged bark of a tree, a wound on the leaves.
Secondary infection occurs in the summer, when a whitish, viscous exudate containing a large number of bacteria begins to stand out from the cracks on the trunk and branches of the tree. In the open air, it is drawn out in the form of thin threads and is easily carried by the wind. Less commonly, infection occurs through garden tools or during vaccination.
Symptoms of a bacterial burn of a pear (photo)
The disease has the following symptoms:
• delayed opening of the kidneys, and then their blackening (at the same time they do not fall off, but remain stuck on the branches),
• blackening, wilting and drying of flowers (if the infection occurred during flowering),
• blackening and twisting of shoots, leaves.
• reddish brown stains on the bark, viscous milky exudate is released from the cracks,
• The affected wood tissue swells and flakes off (this is the last stage - the tree is dead).
As a result, the pear tree looks charred (hence the name of the disease).
Signs of a Bacterial Pear Burn
Bacterial Burn Prevention
Infection of the orchard with a bacterial burn can be prevented if prevention is carried out in time:
• observe the cleanliness of plantings - weeding (many wild plants are incubators of the pathogen of this disease) and the destruction of wild fruit trees (especially hawthorn),
• spraying plantings against various diseases that weaken the immunity of trees,
• fighting insect pests that transmit infections between plants,
• cultivation of varieties resistant to bacterial burn,
• purchase of seedlings in proven nurseries,
• дезинфекция садовых инструментов при обрезке деревьев,
• регулярный осмотр садовых насаждений позволит обнаружить заболевание на ранней стадии и своевременно предпринять меры,
• winter control of suspicious seedlings: sprigs are cut from labeled specimens, placed in water under room conditions and waiting for buds to open. Conclusions about the presence or absence of infection are made as the leaves appear.
What is a bacterial burn of a pear?
Bacterial burn - a dangerous disease that can finally destroy not only the harvest of pears, but also the trees themselves.
From the very name of the disease it follows that the disease is not fungalas many others as well bacterial.
The culprit of the occurrence of destruction of the tree is the bacterium Erwinia Amilovora.
For the first time outbreaks of the disease recorded in the 18th century.
Today the disease is already widespread around the world.
Symptoms of the disease:
- inflorescence blackening is the starting symptom. The inflorescences become black, dry up and remain on the tree in such a state, do not fall,
- the kidneys darken, becoming black, dry up, but do not fall off,
- the leaves turn black, the branches are all parts of the tree.
As a result, the black shroud covers the entire tree, coming down from the top. The trunk of the tree itself blackens, it finally dries out. The result of disease activity is a lifeless, dead tree.
At the final stage of the disease, when rescue is unlikely, the tree is covered with brown stains, white drops form on it.
Treatment of pear burns is difficult. Home - timeliness. If the moment is not missed, and there is hope for the salvation of the pear, it is advisable to apply:
The method is number one, both against fungal and anti-bacterial diseases of the pear.
The strongest tandem against the problem - copper sulphate with lime milk. The combination has a pronounced antibacterial effect. It is important to properly connect the components.
With insufficient content of copper sulfate, the mixture will lose its “lethal” force, and if it is excessive, it will burn the leaves.
Treatment with the solution should be carried out five times a year:
- the first time is the period of appearance of the kidneys,
- the second time - at the time of their dissolution,
- the third - after flowering,
- the fourth - 14 days after the previous one,
- the fifth is after harvest.
Only in this way can you save the trees from the disease.
However, if there is no improvement, or the spread of the disease is noticed, then the bacterium is mutated and insensitive to this method.
Such cases are not uncommon. In case of inefficiency, it is necessary to resort to spraying with other fungicidal preparations, Radical treatment not one tree, but the whole planting is the destruction of the affected pear.
If it is obvious that the pear is hopelessly captured by the pest, it should be uprooted and burned right on the spot.
When moving to another place, the probability of spreading the disease to other pears is high.
Bacterial pear burn: treatment. Pear disease
Pear - is one of the most common garden trees, which is highly valued by gardeners because of the tasty and healthy fruits. However, this cultivated plant, like all others, is subject to a wide variety of diseases. One of the most formidable is a bacterial burn of a pear.
Treatment can be quite long and not give proper results, especially if you use universal remedies against bacterial infections.
Often gardeners lose a lot of time on these useless manipulations, and when they understand what they are dealing with, it can be too late to save a tree.
So, what causes pear blight? Treatment can only be successful when we know exactly what we are dealing with. The causative agent of infection are bacteria Erwinia amylovora.
They spread from a diseased tree to a healthy one, with high humidity and moderate air temperature being the most favorable factors for the development of an infection.
However, there is no age distribution of the disease.
The most good result can be obtained when treating a bacterial burn of a pear with antibiotics. For this purpose, "Streptomycin" is used.
One ampoule of the drug must be diluted in 5 liters of water and spray infected trees with the resulting solution. The first treatment is carried out in June, and then every 3 weeks.
If it was raining or there was very hot weather between treatments, it is advisable to process the garden again.
In the event of the first signs of the disease, it is necessary to immediately treat the bacterial burn of the pear. Preparations should be changed every year. You can use such tools as:
"Fitosporin" helps to resist many diseases of the pear and is used if the plant is badly damaged. However, you should not use this tool often, and even more so every year, since plants have a strong immunity for it.
"Tetracycline" can be applied every 1-2 years. For processing pears need to dissolve 2 tablets in 3 liters of water. Treatment of a bacterial burn of a pear with antibiotics implies the use of "Gentamicin".
This is a very good tool. To prepare the solution, you need to take 1 ampoule and dissolve its contents in 1 liter of water, and then spray the pear. This procedure should be carried out 2-3 times per season.
The antibiotic "Ofloxacin" from a bacterial burn of a pear is considered to be quite a powerful tool that is also used to control pests. When carrying out processing, special attention should be paid to the branches and the trunk of the tree. The barrel is processed from the top to the bottom to prevent the transmission of bacteria.
It is best to prevent the occurrence of the disease than for a long time to treat or destroy half of the garden. There are certain rules for prevention.
To carry out prevention, it is imperative to pull up nearby wild plants.
This is especially true of hawthorn, as this small tree is considered to be one of the main carriers of the infection that provokes a bacterial burn.
Plants should be periodically sprayed with drugs designed to combat pests and diseases that weaken their immunity.
Be sure to show the fight against insect pests that spread the infection between trees. It is best to grow a pear resistant bacterial burn.
It is necessary to acquire saplings only in the checked nurseries, and during carrying out cutting it is necessary to carry out disinfection of tools.
Regular inspection of trees will allow timely detection of the disease and take the required measures to prevent its spread. In the autumn, a comprehensive cleaning and processing of the garden from fallen leaves, fruits, and other debris is carried out. After all, it is in them pest and bacteria winter. Helps to eliminate bacterial spores and digging the ground in late autumn.
Summer pear varieties
Resistant to diseases and pests is considered to be Carmen variety. Fruit maturity occurs in mid-August, they persist for 2 weeks after the break. The fruits have burgundy color, juicy flesh is sour-sweet, medium density with a pleasant aroma of duchesse. This variety is hardy, picky, cold-resistant and almost not affected by infections.
Autumn pear varieties
Among the autumn varieties resistant to diseases and pests include pear Autumn Bukovina. The color of the fruit is golden yellow, with a delicate, pink blush.
Pear pearls quite abundantly, has a soft and juicy flesh, which literally melts in the mouth, sweet-sour taste. Fruits are harvested from September until October.
The variety is frost resistant, practically not affected by scab and bacterial burn.
Tavricheskaya pear belongs to the autumn-winter variety, characterized by high fruiting, good transportability and frost resistance. Fruits are rather large, oval or ovoid.
During the period of maturity, the color of the fruit is bright yellow with a slight pinkish blush. The flesh is juicy, very tasty with a spicy aroma.
The tree is medium thick, characterized by high resistance to scab and bacterial leaf burn.
Winter pear varieties
Pear varieties Highlight of Crimea refers to winter varieties, as it matures only in late October. The fruits are large, golden and above and below, and the rest is bright pink.
The flesh has a cream color, medium density, slightly crunches.
The main advantages of this variety is that its fruit is very well preserved for a long time, and the tree is resistant to various kinds of bacteria and pests.
Late varieties resistant to bacterial burn include Noyabrskaya pear. It is very popular due to its excellent long-term storage properties. Gathering fruits in the first half of October, and they can only be used in early December. This pear variety has excellent taste, thanks to its juicy and fragrant pulp.
A good variety is considered to be Kucherianka pear, which is resistant to scab, frost, and leaf blight. This variety is characterized by precociousness.