Blackberry diseases
Content:
The distribution of cultivated or garden blackberries en masse in gardens on the territory of our country began quite recently. The varieties that are especially popular and widespread were bred in America or in Western European countries, and there the climate differs significantly from the climate in Russia. For this reason, the information given by producers regarding disease resistance of blackberries may not be entirely true. Due to the short period of cultivation of this crop in our country, it has not yet been possible to accumulate sufficient experience in combating diseases, therefore, it is necessary to focus on how its closest relative, raspberries, is being treated. In this article, we will look at common blackberry diseases, as well as treatments.
Blackberry diseases: a description of the main groups of diseases and treatment
In the plant kingdom, diseases are divided into four main groups:
- Into the group non-infectious includes those diseases that develop against the background of improper plant care or bad weather conditions.
- Into the group fungal diseases include those that are caused by fungal microorganisms. Their disputes move by absolutely any means. Wind, precipitation, harmful insects, tools, gardener equipment, and, of course, different parts of the plant can help them in this.
- Into the group bacterial diseases include those caused by dangerous bacteria. They are mostly in the ground.
- Into the group viral includes diseases caused by viruses. They spread in completely different ways, but this is mainly due to the fault of harmful insects.
Diseases of blackberries caused by fungi:
Diseases caused by fungi are the most common and many of them, compared to others found on blackberries. Only 1⁄4 of the disease does not belong to fungal, basically, if a blackberry is sick, then this or that disease is caused by a fungus. They can be recognized by spots, in which the shapes, sizes and colors can be completely different, they appear on foliage and branches. For the passage of spores of a fungal infection into the plant, small scratches, wounds, stomata and lentils, which are on the plant above the soil surface, are sufficient.
Septoria
The cause of this disease is the Septori Rubi West fungus. As a rule, the plant becomes ill due to infected planting material.
If it is hot and dry outside, then the disease may not manifest itself in any way, but as soon as the rains begin, the soil becomes excessively wet and the plantings will thicken, it will show itself. The first signs begin to appear in the last spring month or in the first summer weeks on the shoots of the last year. You can identify the disease by the leaves, on which blotches of light brown appear, turning into white and bordered with dark. You can also identify the disease by the light brown spots that form around the internodes and kidneys. Throughout the summer, this disease is actively spreading and by the end of the season, all the foliage and branches are covered with small black blotches, which represent the fruiting body of the fungus.
Because of this, the disease slows down the supply of nutrients to all parts of the plant, which means that the plant stops developing in the desired mode and the formation of shoots occurs much later.As a result, you can completely lose the harvest, since the fruits not only become smaller, they begin to rot before they have ripened.
The main thing in the fight against this disease is the rapid adoption of treatment measures. First of all, as soon as signs of the disease are found, it is necessary to remove all damaged areas and burn them. The disease can spread due to excessive nitrogen-based fertilizing, so it is important to choose the right fertilizers and use them on time.
Before the buds begin to bloom, it is necessary to carry out preventive treatment by spraying the blackberry bushes with Bordeaux liquid in 1%. For prophylaxis, bio-fungicidal agents can also be used, spraying the plants with them three times throughout the season.
As soon as the first signs of the disease appear, it is necessary to immediately process the leaves and stems using fungicides.
Anthracnose
This disease is caused by the fungus Gloeosporium venetum Speg. Their spores hide in the ground or in uncleaned foliage.
This disease is especially active in cool weather and high humidity. Using a large amount of water when watering, you can provoke the appearance of anthracosis.
The entire bush is susceptible to damage by this disease, but leaf plates, branches and petioles are especially unlucky. Basically, the disease manifests itself towards the end of the spring season. You can determine it by the leaves. Their edges and central veins cover shapeless spots of 2 mm gray-violet. Shoots, in their lower part, and root growths are covered with elongated purple spots, in the center of which there are cracks. After a while, their color turns gray and flakes off along with the bark. Drying and extinction of fruiting branches occurs
Purple spot
This disease is caused by the fungus Didimella applanata Sacc. It appears due to warm winters with high humidity and frequent and large summer and spring precipitation.
It is not easy to notice purple spotting, because first of all it manifests itself by covering with spots the petioles, newly appeared shoots and buds, on foliage, it is shown insignificantly.
At first, vague spots of purple color, but soon turn into dark brown, are visible on young shoots at the bottom or in their middle. Basically, they can be seen where the petioles are attached to the shoot. Where the bark is struck by the disease, cracks appear, the buds dry out, new shoots wither, foliage falls off.
Such a plant blooms very poorly and ovaries appear in very small quantities, which, of course, affects the volume of the harvest. The fruits of such a plant lose their taste due to poor ripening, and a tasteless and rough drupe is formed in them.
If you do not cope with the disease in time and it strongly affects the bush, then the plant's resistance to frost will sharply decrease and most likely it will no longer be able to survive until spring.
Rust
This disease is triggered by the Phragmidium Link fungus. He is not interested in other crops and chooses for his life only a fruit and berry crop - blackberries.
This fungal disease develops in five stages. Begins to be active in May. It can be identified by small dusty inclusions of brown-yellow color, but after a while they become large spots.
Rust at the initial stage seems not dangerous, but because of it, up to 60% of the berries can suffer.
The lower part of the shoots becomes brown in color and sores of a light shade with an orange center appear on them.
If at this time it is not possible to cope with the fungus, then by the middle of summer the surface of the leaf plates will be covered with convex spots of orange and brown. After some time, they will cover the underside of the leaf plates, and after some time, if measures are not taken, the foliage will fall off and the shoots will begin to fade.
Bushes can get rusty not only due to contamination from the outside, which occurs in conditions of high humidity, but also if the bushes are weakened from lack of moisture.
Gray rot
This disease is caused by the fungus Botyrtis cinerea Pers. It becomes the cause of the disease in all crops related to fruits and berries. Spores remain viable in the ground for several years.
As a rule, plants begin to hurt at the time of blooming. But damage occurs to all organs and roots and the aerial part. The disease can be recognized by softened light brown spots on the fruits. After a short time, the drupe begins to cover with a fluffy gray coating. This disease leads to drying out of leaves and shoots and to brown spots on them.
Blackberry fruits and inflorescences are subject to massive rotting during wet and cold summers.
In the autumn period, many black tubercles appear on the affected shoots, where the spores of the fungus are located.
Harvests of berries from diseased plants are not stored and are not edible in any form.
The most effective method to prevent gray mold infestation is to tie the branches on the lower tier onto a trellis at a distance of 60 centimeters from the ground, and cut off anything that cannot be tied down, preventing them from dropping below this level. In order for the branches to be well ventilated, they must be fanned over the trellis.
All fruits on which rot appears or that are damaged during the weather must be removed.
Chemical preparations such as Horus will help to cope with this disease. Processing is carried out before flowering or after harvest.
Phylostictosis
This disease has several pathogens, therefore, the signs by which it can be identified are different. If a fungus such as Phyllosticta ruborum Sacc is the cause of the disease, the leaves will be covered with small whitish blotches. If it is a fungus such as Phyllosticta fuscozanata Thum, then the leaf plates will be covered with dark brown spots, while their size will be large, and there will be a light border around. After some time, black blotches will appear on the leaves.
In the treatment of the disease, it is necessary to start immediately, otherwise the bushes will weaken, the leaves will peel off, and you will not have to expect a decent harvest.
Phylostictosis can be treated with fungicides. It is necessary to spray the plant twice, in the spring and summer.
Powdery mildew
The disease develops due to the fungus Sphaerotheca macularis Wall. The development of the disease occurs in the first summer month, it develops especially actively with high humidity. Suffer from it
shoots of the first year of life, fruits and foliage. Define powdery mildew it is possible on a whitish powdery bloom.
If you do not start treatment at the initial stage of the blackberry disease, the plant stops developing, deformation and reduction of berries occurs, and they also begin to smell unpleasant.
As soon as signs of the disease were noticed, it is necessary to immediately start processing the plant, using Fitosporin for this. The procedure is carried out three times at intervals of two weeks.
Resistance to viral diseases:
Blackberries are not too susceptible to viral diseases, unlike raspberries. Thanks to her strong immunity, even in case of illness, she does not tolerate it badly. However, it is worth knowing about them, because if you leave them unattended, you can lose your harvest.
Curl
This disease is quite rare and if it appears, then last year's shoots suffer from it for the most part. You can determine it by the leaves, curling downward. Their inner side becomes bronze in color, veins glaze and become rigid. The flowers are deformed and the fruit ovary stops.
Mosaic
Blackberries infected with this virus can lose their resistance to cold weather and die in winter.
If yellow and green spots appeared on the leaf plates scattered in a chaotic manner, then this indicates the presence of a disease. After a short time, a slight deformation of the foliage occurs and bulges appear. Poor quality planting material or leaf aphids can cause mosaic infestation.
Yellow mesh
A viral disease similar in features to non-phenolic chlorosis. It appears due to a lack or, conversely, an excessive amount of a number of mineral elements. The cause of the disease is often raspberry aphid. You can recognize the disease by the yellow leaves. The disease stops the development of shoots.
Ring spot
Ground-dwelling nematodes are responsible for the spread of this virus. In a diseased plant, a slight deformation of the leaves occurs and slightly noticeable yellow spots appear on them. The spots are clearly visible in the spring and autumn, but in the summer it is very difficult to notice them. Such a bush becomes very fragile and brittle.
Rules for combating diseases caused by fungi:
Until some time ago, there was no way to replace chemicals with anything in order to cope with fungal and bacterial diseases. It was believed that the safest method of prevention for plants is their treatment with preparations containing copper. To date, many alternatives to those that contain chemistry have appeared on the shelves of specialized stores. It is now possible to cope with fungal and bacterial diseases with the help of harmless biological preparations. To create them, strains of bacteria and fungi are used that have the ability to kill their close relatives.
The choice is large, so everyone can choose the drug that they like best for taking preventive measures and for fighting diseases.
Bordeaux mixture is used at the very beginning of spring. With the help, the whole plant and the root circle are processed. Prevention should be carried out before the buds begin to bloom.
Trichodermin used to treat disease. Spraying is carried out as soon as the buds begin to bloom and with a break of two weeks.
Oxyhom can be used during the second treatment after the buds have blossomed, but before the plant begins to bloom.
Drugs such as Fitolavin and Fundazol they showed themselves well when processing bushes with a disease that is already clearly manifesting itself. Processing is carried out twice during the season, with breaks of 30 days.
Plants can also be treated using chemicals, for example, Topsin... Such processing is possible only before the bush begins to bloom and after the entire harvest has been collected.
During autumn processing, you can use Pharmoyd, with which those shoots that remain for the winter are sprayed.
If there are obvious signs of a blackberry disease, which manifest themselves in summer, in the spring or autumn, copper sulfate is used for processing, with which, using a watering can, the bushes and the earth are watered.
How to avoid blackberry viral disease:
To date, there are no means that can definitely cope with viral diseases. In order to avoid them, it is necessary to carry out preventive measures:
- Firstly, purchase planting material only in nurseries or specialized stores, having previously inspected the seedling.
- When harmful insects appear, immediately start processing the plant in order to get rid of them.
- Regularly inspect the plant and, in case of an infectious disease, remove it from it and burn it, preventing the infection from spreading.
- Three times it is necessary to carry out the treatment using drugs that have antiviral properties. Prevention is carried out at intervals of two weeks.
Diseases of blackberries caused by bacteria:
Stem and root cancer
This disease occurs due to the bacterium Agrobacterium tumefaciens, which lives in the ground.The disease affects the root system, branches, which are covered with bumpy growths of brown color on the outside and light on the inside.
The development of shoots stops, the leaves begin to turn yellow, the root growths become thin and weakened. Productivity drops dramatically and the plant loses its ability to withstand frost and dry periods.
Small wounds on the plant are enough for infecting cancer, so it is necessary to approach planting activities with all responsibility and be extremely careful with the root system so as not to damage it.
In case of illness, the plants are uprooted and burned. The rest of the plants are treated with fungicide twice.
If the variety is especially valuable, then you can try to save it. To do this, you need to remove it from the ground, remove all cancerous growths, lubricate the areas with a mixture that will contain clay, cow dung and biofungicide.
Witch's broom
Mycoplasma - unicellular microorganisms cause this disease. In the center of the bush, numerous thin, low-height shoots begin to appear, the development of which practically does not occur. As a rule, the disease occurs in the case of a weakening of the plant due to prolonged drought, freezing.
If a disease is detected, the plant must be immediately removed and burned. All other plants are processed by Farmaird, but only after the entire crop has been harvested.
The reasons why diseases appear in blackberries:
At the moment when the fruit is ripening, high temperatures and direct sunlight can harm the blackberry. First of all, berries suffer from them. Their color begins to turn white and they begin to dry. If there is sultry weather outside for a long time, then the bush itself suffers. He ceases to have enough liquid, burns appear on the leaves and stems, and as a result, the weakened shoots dry out and die.
For this reason, in the southern regions, when choosing a place for planting blackberries, one should give preference to semi-shady areas and regularly conduct irrigation activities using large amounts of water during especially hot periods.
Often, gardeners wonder why the foliage begins to turn yellow in the spring. The cause may be bacterial cancer or yellow mesh, however, it is often caused by non-infectious chlorosis. This is due to the fact that the plant is experiencing a shortage or, conversely, an overabundance of some element, the reason may be stagnation of water in heavy soil.
Complex mineral fertilizers in liquid form can help to avoid this.
The key to plant health and good yields is following agrotechnical rules.
The diseases listed above most often appear due to high humidity, thickening, lack of good ventilation, and the use of dirty tools when working with a bush.
The best prevention for a plant will be such events as:
The correct choice of a site, taking into account the needs of the plant for the climate and soil. Of course, it is best to choose varieties that are highly resistant to disease, winter cold and long periods of drought. Buy seedlings only in proven places and carefully inspect them before buying. In case of any doubts, it is better to refuse to purchase. Planting should be carried out at a distance of 2 meters from each other. Pruning shoots in the spring and summer seasons so that there is no thickening and they can be well ventilated. Bushes of raspberries, strawberries, and strawberries should be as far away from blackberries as possible. Regular weeding is a good preventive measure against the spread of diseases. The lower shoots, located at a height of 50 centimeters from the ground, bear very little fruit, but in contact with the ground they can get sick, so they must be cut. As soon as the whole crop is collected, all old shoots are cut under base and burned. All fallen leaves and any other plant debris must be removed from the site in the autumn and with the onset of spring.Also, loosen the soil, thus killing spores and microorganisms, mulch using humus for this. Regularly inspect the bushes so that at the initial stage you can detect blackberry diseases or harmful insects and carry out treatment in time. All damaged areas must be removed and burned. so that the soil does not dry out and the liquid does not stagnate in it. At the moment there are many biological means with which you can process plants without causing harm, so feel free to carry out prevention with the help of them, but chemicals only in case of urgent need.
Outcome
If you follow agrotechnical rules, take a responsible attitude to the choice of a seedling and a place for planting, then you can never encounter any of the diseases listed above. If you still cannot avoid this, then you are already familiar with the rules of behavior in these cases.