Description and treatment of common diseases of black and red currants

Currants, regardless of type, can be affected by a large number of diseases. They can be bacterial, viral or fungal in nature, which determines the rate of spread of the infection, the main signs and features of treatment. To avoid diseases, you need to carry out proper prevention and follow the basic rules of agricultural cultivation. This strengthens the plant’s defenses and helps prevent the death of the bush and loss of yield. The effectiveness of planned measures depends not only on the chosen drug, but also on climatic conditions and the specifics of the variety.

Powdery mildew

In seasons with humid, warm weather, berry plants are attacked by a fungus from the order Powdery mildew. Affected plants lag behind in development and often freeze completely in winter. Characteristic signs of damage are:

1. The onset of the disease occurs at the end of flowering of the bushes, when a light gray erasable coating, similar to flour, appears on the tender tops.
2. Diseased leaves remain small, undeveloped and dry out on the branches.
3. Infected shoots become distorted, stop growing, and their resistance to heat and frost decreases.

Treatment

Fresh plaque can be washed off with soapy water. This method can be used if the disease has just appeared and the lesion is of a single focal nature. In case of massive damage to branches, they need to be cut out and burned, and the bushes should be sprayed with Fundazol, Fitosporin or other fungicides. In case of group infection of bushes, 4 treatments need to be carried out: before and after flowering, after harvesting and 14 days after 3 sprayings. As a preventive measure, it is worth removing fallen leaves at the end of the summer season and burning them.

Glass rust

Goblet rust is a disease of blackcurrant caused by a fungus. The causative agent is called Puccinia ribesicaricis Kleb.

Causes

The fungus develops most actively due to high humidity. At the end of the growing season, teliospores appear, which, after wintering, awaken in a different form. The infection begins in early spring and develops very quickly during this period, especially if there has been rain.

Symptoms

The disease affects black currant leaves. At first they turn yellow, and on the back side orange-colored pillows form, where the fungus is located. If you do not respond to the symptoms in any way, then at the end of the warm season the entire leaf below will be orange-red and hard, covered with fluff. Young shoots will not be able to develop normally, which will negatively affect the formation of the bush.

As soon as the ovaries appear, rust will transfer to them. The berries of a diseased plant should not be eaten.

Treatment

First of all, it is recommended to inspect the entire plant and identify sore spots. Affected leaves must be torn off. It is worth remembering that spores can spread to other parts of the bush, so they should be treated and burned. Drain the soil under the currants and fertilize them later.

Recommended Treatments

1. Previkur. To spray currants, use 1.5 ml of the drug per 1 liter of water. It is worth remembering that the drug is dangerous for people, animals, bees, and fish.
2. Speed The norm is 1 ml of product per 10 liters of water. At the same time, constant use of Scor causes addiction in plants, so after a couple of procedures it is better to switch to another product.
3. Fitosporin. Treatment can be carried out throughout the entire growing season and ripening of berries. Spray according to instructions in the evening.
4. Topaz. Prepare the drug from 2 ml of the product diluted in 10 liters of water. If necessary, re-treatment is carried out after 10 days.
5. Copper sulfate. For treatment, take 10 liters of soapy water, a teaspoon of vitriol and 200 ml of boiling water. First, everything is placed in a bowl with hot water, and then mixed until smooth. After this, they add it to the soap and spray the leaves and soil under the plant.
6. Bordeaux liquid. For processing, it is best to use a 1% solution, and the latter is carried out 2 weeks before harvest.

Anthracnose

Wet weather, thickening of plantings, and the presence of weeds contribute to the development of this fungal disease. The development of anthracnose is characterized by the following symptoms:

1. The pathogen mainly affects leaves, petioles and stalks.
2. The first sign of the disease is the presence of small, several millimeters in diameter, brown spots.
3. After some time, ulcers appear at the site of the spots, diseased leaves dry out and fall off.

The fungus that causes anthracnose overwinters in fallen leaves, so one of the effective measures to prevent the disease is the autumn collection and disposal of leaves.

Treatment

The disease can be cured using Bordeaux mixture: you need to thoroughly spray all the bushes when the first signs of infection are detected and after removing the berries. As a preventive measure, it is recommended to avoid planting a young bush in the place where the affected specimen grew, and also to burn all fallen leaves in the area.

Currant feeding

What to feed

As has been said more than once, compliance with the laws of agricultural technology and proper care make any plant practically invulnerable to diseases and parasites. Fertilizers applied at the right time and in correct proportions also strengthen plant immunity. Each plant has its own dose and fertilizing period.

How to fertilize currants and when is the best time to do this in order to achieve high currant resistance to diseases and pests? If at the time of planting the bush a sufficient amount of fertilizer was added to the ground, then the plant will not need fertilizing for the next two years. Starting from the third year, currants need to be fed at the beginning of the growing season, at the time of ovary growth and after fruiting. In the spring, it is necessary to feed the currants with nitrogen fertilizers, for example, ammonium nitrate at the rate of 60-75 g per bush.

During the period of fruit formation, it is best to use Uniflor-micro as a fertilizer at the rate of 2 tablespoons per 10 liters of water, and after harvesting it is advisable to apply fertilizer consisting of phosphorus and potassium: sprinkle a tablespoon of chlorine-free potassium and double granulated superphosphate under each bush , and then water the bush with ten liters of water if the weather is dry. If it rains, just add fertilizer to the soil. All fertilizers are scattered around the perimeter of the crown of the bush, away from its center.

Septoria

Septoria (white spot) is also most likely to occur in rainy, cool summers. Brown spots appear on the leaves, which over time become whitish with a brown border. With severe damage, the spots enlarge and merge with each other. The leaf dries up and dies. The yield of diseased bushes is reduced by 1.5–2 times.

Treatment

• Treatment with copper sulfate at intervals of 1 time every 2 weeks. The procedure must be carried out three times, the first - after the foliage has completely bloomed;
• Destruction of infected parts of the plant;
• Thinning branches to avoid excessive thickening of the bush;
• A preventive control measure is digging up the earth around the bushes, removing grass and leaves.

Bacterial diseases of currants

Bacteriosis is caused by non-spore-bearing bacteria that penetrate plants either through various damage or through natural means (through the stomata of leaves). Blackcurrant is affected by bacterial spot; no other species have been recorded.

The pathogen is activated in hot weather and high humidity. On the leaves of the crop, watery spots appear between the veins, which turn black over time. The plates change color, die and fall off.

The infection is stopped with treatments using:

• drug Maxim;
• Bordeaux mixture;
• copper sulfate;
• drug HOM.

Severely affected bushes are removed and burned.

Rust

Rust is red bumps on the back of leaves that merge into orange stripes as the disease spreads. Fruits may also be affected. Excessive spring watering can provoke the disease. Rust pathogens live on conifers or on a marshy plant - sedge. If there is a wetland or coniferous plantings near the garden plot, then for growing currants it would be better to choose varieties that are resistant to rust.

Blackcurrant varieties with high immunity

It is best to plant disease-resistant blackcurrant varieties. In this case, the likelihood of encountering problems is much lower. Experts recommend the following varieties: Binar, Kipiana, Katyusha, Pamyati Vavilova, Kupalinka, Klussonovskaya, Titania, Dachnitsa, Perun and Yadrenaya.

Binar

Kipiana

Katyusha

In memory of Vavilov

Titania

Klussonovskaya

Knowing what diseases black currants have, any summer resident will be able to take preventive measures and, if necessary, cure the plant. The most important thing is not to ignore obvious symptoms, otherwise there is a risk of losing not only one bush, but also neighboring crops.

Currant terry

A specific disease of currants is caused by viruses and can completely destroy the berry plant; it is transmitted by pests: mites, aphids, bedbugs. The main signs of infection are as follows:

1. The formation of a large number of shortened shoots, the so-called “panicles”.
2. The leaves lose their specific currant smell and become rough, shiny, and veiny.
3. Flowers and perianths turn into small narrow petals of a rich lilac color, the pistil becomes thinner and takes on a filamentous appearance.
4. Berry setting stops and plant development is delayed for up to 2 weeks.

You should be careful when purchasing planting material, as the virus can penetrate the area with seedlings and cuttings.

Botanical description

Currant is a bush from one to two and a half meters high with alternate palm-shaped three- to five-lobed leaves with large teeth along the edge. Currants bloom in raceme inflorescences, consisting of 5-10 small flowers with five petals, five stamens and five sepals. Berries up to 1 cm in diameter ripen by the end of July. The currant bush can begin to bear fruit the next year after planting. Currants are shade-tolerant, but develop better in well-lit areas.

Of the numerous plant species, the most commonly cultivated are black currant (Ribes nigrum), red currant (Ribes rubrum) and white currant (Ribes niveum); recently, yellow currant has also become popular. The main number of berries is formed on the shoots of the first, second and third years of life. Currant berries are a storehouse of organic acids, vitamins, macro- and microelements necessary for humans.

Black currant is useful for vitamin deficiency, hypertension, atherosclerosis, bronchitis, renal and hepatic colic, gastritis and other diseases. For the treatment and prevention of diseases, not only berries and products made from them are used, but also the leaves and flowers of the plant. However, currants themselves are sometimes susceptible to diseases and invasions of insect pests, and the gardener is faced with the task of promptly and correctly diagnosing currant diseases so as not to be late in treating them. As a preventive measure, proper planting and care of currants, as well as their preventive treatment, are very important.

• Boxwood: cultivation, propagation, types and varieties

Leaf marginal necrosis

The disease is non-infectious and is caused by excess chlorine in the soil. It appears towards the end of summer. A wide dry strip of ash-gray color forms along the edges of the leaves. There is a clearly defined border between this strip and healthy tissue. If such symptoms are detected in the next season, it is necessary to fertilize with urea twice (in the spring after the buds swell and after the end of flowering) (the norm is 20–30 g/m2).

Marginal necrosis of currant leaves has a clearly defined border.

If the dry strip has a darker color and its border is blurred, then this indicates potassium starvation. Accordingly, next season, at the beginning of summer, you need to add a solution of potassium monophosphate to the soil - add 20 g of fertilizer to a bucket of water and water the bushes (the norm is 20 g/m2).

How to process currants - prevention

Treatment in spring

Work with currant bushes begins in early spring, before the buds wake up and sap flow begins. First of all, you should carry out “hot” processing of currants. It is carried out for the purpose of prevention from pests and diseases and to ensure full development and subsequent abundant fruiting. Heat the water to 80 ºC and pour it over the currant bushes from a watering can with a divider. Ten liters of hot water should be enough for three bushes.

After a hot shower, it is very advisable to prune the currants - remove damaged and weakened shoots, lightly trim the tips of branches that have frozen over the winter, thin out the bush if for some reason you did not do this in the fall. When pruning, remove those branches or buds that have been affected by the bud mite. All trimmings must be burned, and sections whose diameter exceeds 8 mm must be treated with garden varnish. After this, you need to clean the area with currants from last year’s foliage, in which the larvae of insect pests and pathogens probably overwintered.

Treatment for diseases

In early spring, before the buds open, spray the currant bushes and the soil under them with a two percent solution of nitrophen or karbofos - this will protect the plants from almost all diseases. After a while, to be sure, treat the currants with Bordeaux mixture, and when real spring begins and the currants begin to grow, from time to time you can spray the currants with foundationazole for preventive purposes.

Pest treatment

How to spray currants so that they are not affected by pests? Yes, all the same karbofos or nitrophen, which do an excellent job of their preventive function and protect currants not only from diseases, but also from pests. The fight against bud mites can be carried out at a temperature not lower than 20 ºC, otherwise after spraying the bushes must be wrapped in polyethylene. Don’t be lazy, otherwise you will have problems with kidney mites. To prevent the currant bushes from being harmed by the moth, at the beginning of the growing season, lay roofing material around the bushes, sprinkling its edges with earth. When the flowering ends and the fruits appear, the roofing material can be removed.

Autumn treatment

In the fall, you will need to do annual pruning of currants. All branches older than five years are removed because they are no longer very productive and take up too much space. In addition, you need to cut off to a healthy part or completely all the shoots in which the glass beetle has settled - they are easy to identify, they are withered and dried out. If possible, remove all shoots infected with bud mites, covered with powdery mildew, all weak and too thin zero shoots to the base of the bush.

• Spathiphyllum

If you have an old bush, start rejuvenating it, just don’t overdo it with pruning: if you need to remove too many old branches, do it in three stages, that is, over three years - cut off a third of the branches every year. And do not forget to treat cuts of thick branches with garden varnish and burn the trimmings.

After pruning, it is time to carry out autumn preventive spraying of currants with a two percent solution of karbofos or a one percent solution of colloidal sulfur. Spray the soil under the bushes generously. Spraying should be done in warm, windless, dry weather.

Striped mosaic

If the leaf veins turn yellow and their number is constantly increasing, then this is a sign of infection with a viral disease. It is useless to fight with striped mosaic, just like with terry. The virus is spread by insects and persists in the tissues of the bush. Therefore, the only measure is to burn the bush. The soil at the site of the affected plant can be treated with a solution of potassium permanganate.

Viral diseases of currants

Striped mosaic
is not a rare and incredibly dangerous disease. The plant is infected with this disease by ticks and aphids, and can also be infected by a person when pruning a seedling with untreated pruning shears, if the infected plant has been pruned before.

The leaves of diseased shrubs become lighter, yellow stripes of a rich shade appear, which subsequently expand. Most often, such a mosaic is located next to the main veins of the leaf.

Measures to combat striped mosaic

removal of diseased plants; disinfection of instruments; examining other plants for signs of a similar mosaic. It is better not to plant plants in an infected area for 5 years. Unfortunately, it is impossible to cure an infected plant.

Terry

- This is a viral disease, which, like striped mosaic, cannot be treated. The first sign is that the currant completely stops bearing fruit, the shape of the leaf changes: it has three blades instead of the usual five; the shape of the leaf plate itself becomes denser, longer and sharper; leaf color is darker; the veins are thicker and clearly fewer in number; There is no currant smell as such. The bush begins to bloom later than the others.

The inflorescences become smaller and take on a double shape. Their color changes to a dirtier color, and the flower stalks fall off. The fruits do not set at all or appear, but are small and have an unsightly shape.

Measures to combat terry

Diseased shoots are removed immediately when signs of the disease are detected and burned;
instruments must be thoroughly disinfected. If the entire bush is affected by the disease, it needs to be gotten rid of, and the place where it grew is treated and left fallow for 5 years. To prevent the currant bush from being affected by diseases, it is necessary to create comfortable conditions for its existence: timely application of fertilizers and watering, sanitary and formative pruning and, of course, collecting and removing leaves that have fallen from these plants in the fall. An important stage: preventive treatment of shrubs against diseases. Inspect the leaves and shoots from time to time, because many currant diseases can be cured quite quickly, especially if the infection was diagnosed at an early stage.

Tuberculariosis

The fungus is caused by polyphage Tubercularia, which attacks all types of currants (black, red, golden, white). Annual growth and young shoots of shrubs are mainly affected.

The fungus penetrates the bark through damage and cracks. The pathogen is tenacious and tolerates sub-zero temperatures well.

Signs:

• red tuberous spots on the underside of leaf blades;
• the appearance of reddish bumps on the branches;
• drying of the tips of the shoots;
• necrosis of the cortex.

The disease is treated after picking berries by spraying with solutions of Khomecin, Captanol or Topsin. For prevention, Bordeaux mixture (1%) is used. It is recommended to exclude any mechanical damage to the bark, shoots, and branches of the plant.

Currant varieties resistant to diseases

To be sure of preventive measures, it is recommended to plant currant varieties with high resistance. Since there are 4 types of currants, a list according to their affiliation is proposed:

The specified names of varieties refer to hybrid varieties. The berries have a special taste. This does not change the shape and color of the currant: it remains just as tasty, large and juicy.

Effective ways to fight diseases

One of the mandatory techniques in the fight against diseases is the following:

• Collection of affected leaves and ovaries.
• Cutting out diseased branches and ends of shoots.
• Digging up soil under bushes.
• All collected infected parts of the plant must be disposed of by burning or burying in the ground to a depth of at least 1 meter.

When viral diseases occur, mechanical destruction of infected plants and planting material remains the only way to prevent the spread of infection. To prevent the development of currant diseases and treat in case of infection, successive treatments with the following drugs are effective.

Colloidal sulfur

To combat powdery mildew, use a 0.5% suspension of colloidal sulfur, treating the shrubs in 5 periods:

• before flowering;
• immediately after flowering;
• 10 days after flowering;
• 20 days after flowering;
• after harvest.

To prepare a 0.5% suspension of colloidal sulfur, take 50 g of sulfur powder, stir it in a small amount of warm water until it becomes mushy, then gradually add water to a total volume of 10 liters.

Bordeaux liquid

Spraying with a 1% solution of this drug is effective for the treatment and prevention of anthracnose, spotting, and rust. The main treatments are carried out in 3 periods:

• immediately after flowering;
• 10 days after flowering;
• after harvest.

Convex red spots on currants

Similar red spots appear on currant foliage in the summer, and their color is not always red, its color can range from burgundy to dark red. The affected parts of the foliage protrude slightly above the surface of the leaf blades.

More often, this disease affects white or red varieties of currants. Blackcurrant is affected much less frequently by it.

The main reasons for the appearance of red raised spots on currant leaves are:

• anthracnose;
• glass rust;
• the appearance of gall aphids on plants.

Currant anthracnose

The first symptom of this disease is the appearance on the leaf blades of small brown or black spots no larger than 1.5 mm in size. In their center you can feel small tubercles. Gradually, these spots begin to grow, gradually connecting with each other.

Over time, the entire affected berry perennial may disappear.

Ways to combat currant anthracnose:

• all affected foliage should be collected and immediately burned outside the garden area;
• diseased bushes should be treated at least 4 times per season with Bordeaux mixture: before the leaves appear, after the plant has bloomed, a couple of weeks after the second, after picking ripe berries;
• Spray the currants with Nitrofen (3%) before the leaves appear and after leaf fall.

Important!

Currant leaves should be sprayed on both sides!

Goblet rust on currants

The main symptoms of currant goblet rust disease are as follows:

• on the upper side of the foliage specks of red color with a yellowish tint form;
• on the reverse side of the leaf blades, goblet-shaped growths form - fungal spores “live” in them;
• Over time, the leaves begin to turn yellow and fall off prematurely.

This disease negatively affects the ripening of fruits. As a result, productivity decreases sharply.

Interesting article:
Proper care of currants in the fall and preparation for winter
Interesting!

This disease most often occurs in areas that are located near rivers, lakes and other bodies of water - sedge grows there, which is a temporary refuge for spores and goblet rust fungi.

Fighting the disease includes:

• collecting all fallen leaves and burning them outside the garden;
• all currant bushes are treated with Bordeaux mixture or other copper-containing preparations;
• the soil in the root zone should be treated with colloidal sulfur (1% solution).

Important!

To prevent the disease from spreading throughout the garden plot, sick and healthy currant bushes are sprayed with copper-containing preparations every couple of weeks.

White coating on currant leaves

If a white coating appears on the foliage and shoots of this berry crop, then an experienced gardener immediately understands that the plant has been affected by powdery mildew. The spores of this disease can survive even in extreme conditions - extreme heat or harsh winters with severe frosts. During the winter, the spores of this fungus “hide” in fallen leaves.

For which diseases the first sign is a white coating will be described below.

Powdery mildew on currants: control measures and description of the disease

If a white coating appears on the vegetative part of currant bushes, gardeners immediately understand that this is the main symptom of powdery mildew.

There are several types of this disease:

• European powdery mildew, the main symptom of which is the appearance of a thin white cobweb on shoots, fruits and foliage. This type of fungal disease mainly affects red currant bushes.
• Spheroteka (or American powdery mildew). In this case, a white powdery coating forms on the leaves, which feels like a felt covering to the touch.
• Foliage and fruits affected by this disease fall off, the stems stop growing and become twisted. This is a very unpleasant and dangerous disease.

The fight against powdery mildew on currants includes:

• all diseased stems must be removed and burned outside the garden area;
• before the start of sap flow, all berry bushes are treated with iron sulfate (3% solution);
• You can treat currant bushes against this disease with Fitosporin, Phytodoctor and other similar fungicides.

One of the most effective folk methods of combating powdery mildew is treating currants with iodine solution. To do this, dissolve one bottle of iodine in a bucket of water and spray the plants once every 3-4 days.

Gray rot on currants: how to deal with the disease

This fungal disease primarily affects currant berries, which begin to rot and disappear. Their flesh becomes loose, and small brown pads appear on the skin, in which spores “live.” The foliage becomes covered with brown spots, and there are lumps of mold fungus on the shoots.

The following preventive measures are effective against gray mold disease of currants:

• before the start of sap flow, all bushes are sprayed with Bordeaux mixture (3% solution);
• during the same period, as well as after harvesting the fruits (until the last ten days of August), the plants are sprayed with Zircon;
• all affected parts of plants are removed and burned;
• Before buds open and after leaf fall, currant bushes are treated with a urea solution (0.7 kg of the drug is dissolved in a bucket of water).

Pests of black currant and their control

Blackcurrant bushes can infect more than 70 insects. Some are very rare or do not cause significant damage. But the most harmful are considered:

• gall midge,
• fire,
• kidney mite,
• bud moth,
• spider mite,
• currant borer,
• currant glass,
• shoot aphid,
• scale insect,
• berry sawyer.

Gallica

Gall midges are mosquito-like insects that lay eggs under the bark or in cracks of stems, flowers, and unopened leaves. The larvae overwinter under currant bushes in spider cocoons. Affected plants develop reddish swellings on the leaves.

Control measures:

• spring and autumn tillage around the bushes;
• treating plants with Bordeaux mixture;
• cutting and burning affected branches;
• spraying currants with Fitoverm before and after flowering.

Ognevka

Moth pupae overwinter in the ground under bushes. In spring, butterflies come to the surface and lay eggs directly into flower buds. The hatched larvae eat the ovaries. The berries on the affected shoots are entwined with cobwebs and dry out.

To prevent damage to bushes by moths, the soil under the bushes is dug up in spring and autumn and mulched with a thick layer of cardboard so that it is impossible for butterflies to come to the surface.

Control measures:

• spraying bushes in early spring with insecticides (Aktellik, Lepidotsid);
• collection and destruction of affected branches and berries.

Kidney mite

A characteristic feature of infection is the overwintering of the tick directly in the affected kidneys. External signs of currant damage are as follows:

1. Buds infested with mites do not bloom in the spring, swell unnaturally and dry out.
2. Mites born in a dead bud move to other shoots, infecting new buds, where they are able to produce another 1-2 generations.
3. Buds infected with a small number of mites bloom, forming underdeveloped shortened shoots; the bushes do not ripen and are susceptible to freezing.

The pest is a carrier of the tick virus, so signs of mite infestation are often accompanied by symptoms of this disease.

Aphid

An omnivorous pest that greatly weakens bushes, overwinters on shoots and can subsequently develop on all parts of the plant. Young shoots and leaves are most susceptible to damage.

Features of aphid parasitism are presented below:

1. Generations of insects hatch from eggs in the spring, and with the onset of warm and humid weather they quickly multiply, and the colonization has a wave-like character.
2. Sexually mature light green individuals are visible to the naked eye; colonies are often localized on the underside of leaves and tops of shoots.
3. The affected leaves swell in the form of light bubbles, the shoots become bent and remain undeveloped.

Aphids suck juice from green parts of plants, serve as a carrier of viral infections, and can significantly damage berry plants.

How to get rid of kidney moths

The pupae of the bud moth overwinter under the bark of the currant, and with the arrival of spring, the emerging butterflies lay eggs on the ovaries, which subsequently destroy the hatched larvae.

To prevent the spread of this pest you must:

• destroy fallen leaves;
• thin out bushes and plantings;
• spray with Karbofos, Actellik.

How to deal with spider mites

Spider mites become more active in hot, dry weather. The presence of a mite on the plant is indicated by light dots on the upper part of the leaf blade. On the back side of the leaf you can see a thin cobweb on which the mite lives. Currant leaves affected by mites dry out and fall off in mid-summer.

To combat spider mites during the growing season, use the drug Fitoverm.

Currant borer and glass

Insect larvae of these species infect currant branches and, in a short period of time, with a strong infection, can completely destroy the plantation. Determine the presence of pests as follows:

1. Suspicion of larval infestation should arise if in the spring the gardener observes withering and drying currant shoots.
2. Having cut along such a shoot, you can see inside an elongated dark passage, in which there is either a legless larva of the currant borer beetle or a white caterpillar of the currant glass beetle.
3. The larvae of both species pupate in May, which occurs in June, and the larvae hatch again in July, damaging the shoots.

Determined by characteristics

A gardener or summer resident is obliged to regularly inspect the bushes on the site. If the plants are healthy, then the leaf blades, shoots and berries will have the color, size, and shape characteristic of the variety. But unstable weather conditions, incorrectly carried out agrotechnical measures, and proximity to a disease-infected area can lead to the loss of natural immunity of plants. And if the deadlines are missed, then the summer resident may lose not only the crop, but also the bushes. Below we will talk about how one or another currant disease can be determined by external signs in order to choose the right chemical or folk remedy and treat the bushes in a timely manner.

Red raised spots

Typically, red raised spots appear in the summer.
They can be either burgundy, red, or dark red. The affected areas even protrude slightly above the leaf blade.

They appear more often on red or white currants, but such changes on the leaves can also be noticed on black ones.

The causes of the phenomenon may be:

• anthracnose;
• glass rust;
• pest - gall aphid.

We will discuss diseases and measures to combat them in more detail below.

Anthracnose

It affects leaves, on which very small spots of brown and black color appear with a diameter of about 1 mm. Small tubercles are felt in the center. After some time, the spots increase in size and connect with each other.

With anthracnose, the leaves begin to dry out and curl upward at the edges.

As a result, the entire bush disappears. Measures to combat anthracnose:

1. Collecting and burning leaves.
2. Treatment of bushes four times with a 1% solution of Bordeaux mixture: before buds open, immediately after flowering, 10-14 days after flowering, after harvesting.
3. Treatment with 3% Nitrofen solution. Spraying with this drug is carried out twice: before the buds open and after the leaves fall.

Why currant leaves curl and how to treat them is described here.

The treatment is carried out so that the solution falls on the lower part of the leaf blade.

Glass rust

With goblet rust, yellowish-red spots appear on the upper part of the leaf blade, and if you look at the back of the leaf, you can see goblet-shaped formations in which fungal spores develop. This disease significantly reduces the yield of currants, and the leaves turn yellow and crumble.

Usually, goblet rust appears where there is a nearby body of water on which sedge grows - an intermediate host for this type of fungus.

Fighting methods:

1. Burning fallen leaves.
2. Treatment of shrubs with a 1% solution of Bordeaux mixture. You can spray currants with Topaz or use copper oxychloride.
3. It is advisable to treat the ground under the bushes with a 1% solution of colloidal sulfur.

To prevent the spread of goblet rust, it is necessary to treat not only infected bushes, but also neighboring healthy bushes after 10-14 days.

White plaque

If a white coating appears on the vegetative organs of currants, we can confidently assume that an infection with powdery mildew fungus has occurred. The spores of the parasite are very hardy. They easily tolerate severe frosts and heat, living in the soil or fallen leaves.

The affected berries shrivel and begin to fall off, and the shoots stop growing. The bushes become weak, and if they are not treated with fungicides, they disappear.

We will discuss in more detail below what diseases white plaque is a sign of.

Powdery mildew

A white coating forms on the shoots, leaves and fruits of currants. There are two types of powdery mildew:

1. European powdery mildew. In appearance, it resembles a thin white cobweb that forms on the vegetative organs of currants. Red currants are mainly affected.
2. American (spheroteka). A white powdery coating, reminiscent of felt, forms on the leaf blade.

Affected berries and leaves fall off, and the shoots stop growing and become bent.

Fighting methods:

1. All diseased branches are cut off and burned.
2. Before the buds open, the bushes are treated with a 3% solution of ferrous sulfate.
3. Spray currants with Fitosporin, Phytodoctor, Horus, Paracelsus.
4. Measures to combat dew on currants using folk remedies are described here.

This article will tell you about measures to combat powdery mildew on red currants.

You can use a folk remedy. Dissolve one bottle of iodine in 10 liters of water and treat the bushes at intervals of 3-4 days.

Gray rot

A fungal disease that causes rotting of berries. The pulp becomes loose, and brownish pads form on the surface. Brown spots appear on the leaves, and lumps of mold appear on the branches. Preventive actions:

1. Treatment of bushes in the phase of unopened buds with a 3% solution of Bordeaux mixture.
2. Twice spraying with Zircon. The first time is in early spring, and the second time after harvest, but not later than August;
3. Leaves and infected branches are burned.
4. In early spring and after the leaves have fallen, you can treat the bushes with a urea solution (700 grams per 10 liters of water).

Leaves turn yellow and brown

Currant leaves can change their color due to diseases such as:

• anthracnose;
• terry;
• spheroteka;
• columnar rust;
• spotting;
• scab;
• septoria.

Let's look at some of these diseases in more detail. Read about why blackcurrant leaves turn yellow.

Columnar rust

Yellow or yellowish-brown specks are visible on the leaf blade. And on the reverse side of the leaf small pads appear - columns in which fungal spores ripen.

The affected leaves begin to fall off, and the shoots slow down their growth. The bushes weaken and become defenseless against pests and diseases.

Control measures: treatment of bushes on unopened buds with a 3% solution of Bordeaux mixture. Or spraying currant bushes four times with the same, but 1% solution. Interval 10 days.

For green leaves, it is better to treat the plant with a fungicide. You can use Fitosporin or Phytodoctor.

Striped mosaic

The striped (veined) mosaic of currants, unfortunately, is not curable. A light yellow pattern appears on the leaves next to the veins. The bushes are weakening, and their yield is very low. To prevent the disease from spreading to healthy plants, infected ones are uprooted and burned. The fight is also being carried out against ticks and aphids, which are carriers of the infection.

In those areas where striped mosaic was noticed, currants should not be planted for 5 years.

Scab

Currant scab is often confused with powdery mildew.
Therefore, you need to know their distinctive features well in order for the fight against pathology to be effective. Scab is a fungal disease. Ovaries, fruits, shoots, and leaves are affected. Dark spots with a greenish coating appear on them. And as a result:

1. Leaves die and fall off.
2. The fruits do not develop, become stained and crack.
3. Cracks form on the shoots and the bark begins to die.

The most effective way is to treat plants in early spring before leaves appear with a 3% solution of Bordeaux mixture. Or spray the bushes and tree trunks with a 7% urea solution in early spring and autumn. For green leaves, plants can be treated with Aktara or Horus.

Septoria

Septoria (white spot) is caused by a fungus. Very small brown spots appear on the leaf blades of plants. Later they lighten and become white, but retain a brown border.

The same spots appear on the berries. To prevent and treat the disease, use a 1% solution of Bordeaux mixture during the growing season. In the spring, before the buds open, the bushes and tree trunks are treated with a 3% solution of the same drug.

The disease leads to falling leaves and wilting of the bush. It will not be possible to obtain a harvest from infected plants.

Doesn't bear fruit

Currants may not bear fruit for many reasons, both agrotechnical and under the influence of emerging diseases. And one of these that directly affects fruiting is the terry size of black currants. This is a viral disease that is transmitted from a diseased bush by a bud mite.

Terry (reversion)

Terry disease is a viral disease caused by the microorganism Riber virus

Many very thin branches with narrow leaves appear on the bushes. While currants usually have five-lobed leaves, the infected plant has three-lobed leaves with pointed tips. The flowers become double, bright purple. And completely barren.

The disease cannot be cured. The bush needs to be uprooted and burned.

And since reversion is carried by aphids and mites, it is necessary to treat the bushes against these pests.

The first sign of terry growth is the loss of the specific currant smell of the vegetative part of the plant.

Round and swollen buds

If the buds are round and large, this means that a currant mite has settled in them. And this is the main distributor of the virus that causes such a disease as terry.

Brown spots

Brown and brown spots on the leaves may appear due to ascochyta blight.
This disease is caused by three types of fungi. Spots with a brown border appear on the leaf blade. In the center there is sporulation of a light brown fungus. Brown spots may initially appear, which over time change color to dirty gray. The third group of fungi causes gray spots with a brown border to appear on the upper part of the leaf blade. If infected bushes are not treated, they will gradually shed their leaves. And this, in turn, will lead to the death of the plant.

Measures to combat ascochyta blight: burning leaves, thinning the bush to improve its ventilation, removing weeds and loosening the tree trunk. As well as treating currants with a 1% solution of Bordeaux mixture, Cuprosan or Captan.

White spot

Fungal disease. Many small spots appear on the leaf blade.

The affected leaves begin to dry out and fall off, and this reduces the yield of currants next year.

Control measures: as soon as the crop is harvested, it is necessary to treat the plantings with 1% Bordeaux mixture. In early spring, you can spray currants with Nitrofen or Phytodoctor. They also use drugs such as Fitosporin M and Alirin B. But it is advisable to combine them with fertilizers containing microelements such as manganese, boron, zinc. Be sure to collect and burn the leaves.

Drying of branches and shoots

The reason for the drying out of currant branches and shoots may be the wrong choice of planting site, a long period without rainfall or watering, and more. But in this case, bush diseases can never be ruled out. One of them can cause drying out of individual branches or an entire bush (nectria drying out). Red currants are more susceptible to this pathology. The disease is caused by a fungus. To activate its vital activity, certain conditions are necessary: ​​warm and humid summer and damaged currant bark.

The spores get into wounds on young branches and germinate into them. Red dots appear on the bark, which darken and dry out over time. The bark in this place begins to die and the growth dies. If the disease is detected early, the bushes are treated with Topsin M. If the disease is advanced, the affected branches or even entire bushes are cut and burned.

What to do and how to treat if currant branches dry out is described in this material.

The drug Topsin M is used once during the growing season; more frequent use causes addiction to it.

Also, drying of branches can cause tuberculosis and chlorosis.

Tuberculariosis

Tubercular disease is a disease of currants that is caused by a fungus. Black currants suffer most often.

In early spring, overwintering spores are spread throughout the area and some of them get into wounds and cracks in the bark of young shoots. They begin to feed on plant juices, and the mycelium gradually grows, forming fruiting bodies - reddish-brown pads, up to 2 mm in diameter.

In spring, fungal spores ripen in the bark. Closer to autumn, mass dying off of young currant shoots begins.

To protect the shrub from fungal disease, it is treated in early spring before buds open with a 3% solution of Bordeaux mixture. This operation is also carried out after the leaves have fallen. You can spray currants with a 4% solution of copper oxychloride, but only before flowering begins. In summer, currants are treated with drugs such as Topsin M, Khomecin, Captanol.

Plants that are damaged by all types of fungal diseases should have diseased branches removed. They need to be burned. This will prevent the spread of spores throughout the area and further infection of trees and shrubs.

Chlorosis

Chlorosis is usually caused by a lack of a microelement such as iron in the soil.
The disease affects the upper parts of the shoots and leaves. They become yellow or pale yellow.

The pathology is eliminated by treating the bushes with a 10% solution of ferrous sulfate in early spring.

In case of currant chlorosis, it is not recommended to add unrotted manure to the soil.

Problems not related to diseases and pests

Pests and diseases can damage the flowers, ovaries and shoots of black currant, but in general this shrub is unpretentious in care, grows almost everywhere and for a long time, and does not require special agricultural technology. However, sometimes problems arise with it that are not related to diseases and pests.

Blackcurrant does not bear fruit

There could be several reasons for this problem:

• incorrectly chosen landing site. Deep shade or scorching, sultry sun are unacceptable conditions for the development of black currants. They prefer light partial shade with good illumination;
• acidified soils - optimal acidity level pH 6–7;
• cultivation of non-registered varieties;
• freezing of flower buds as a result of return frosts.
  To prevent this problem on those nights when spring frosts are expected, fires are lit in the garden and smoke bombs are used; When burning old branches in the garden, a double effect is achieved - protection of bushes and trees from frost and the formation of ash - an excellent fertilizer
• insufficient watering. Currants are a moisture-loving crop and, if there is a lack of moisture on hot days, they can shed all their ovaries;
• thickening of bushes with old shoots. It is necessary to regularly carry out thinning pruning, as well as pinching (chasing) young growths.

Black currants dry out after winter

Most often, drying of shoots is caused by damage to the root system. This, in turn, can occur due to root rot caused by stagnant moisture and swampy areas, in addition, the roots can be damaged by moles.

In order to prevent root rot, when planting currants in the fall, drainage should be laid at the bottom of the hole, and in early spring, snow should be shoveled away from their base in time, preventing melt water from accumulating.

You can use acoustic devices against moles (“Krotopug”, “Antikrot”, “Krotogon”). They emit ultrasound, which simulates a danger signal. A cat or cat (if you have one) will also help in the fight against these pests. The Antikrot device effectively repels pests from the site. If the damage to the roots is significant or the bush is old (10 years or more), it is advisable to replace it with a new one.

Kidney mite

The bud mite often causes black currant diseases. It destroys the buds of the plant and harms it so much that there is no need to wait for the harvest. One kidney can contain up to 8 thousand parasites. Having destroyed one bud, the insects move to another.

Symptoms

This disease of blackcurrant bushes has striking manifestations: the bud swells and begins to resemble a head of cabbage. Later it bursts and begins to die. Affected currants bloom poorly and produce a poor harvest. In addition, due to the activity of the mite, the bush begins to hurt - for example, it spreads terry.

Treatment

Before the leaves bloom, it is recommended to carefully inspect all the bushes. Suspicious buds are immediately cut off and burned. If there are too many of them, then the entire shoot is removed. Then you need to treat with the drug. It is important not to miss the migration of the tick from bud to bud; this happens during the budding period.

Chemicals

As soon as the buds begin to form, treatment should be carried out with a low-toxic, non-systemic acaricide. The following drugs are suitable: Envidor, Contos, Oberon. Repeated manipulations are carried out at the end of flowering, and then another 10 days later. More toxic products are allowed after harvest.

Biological drugs

Biological preparations also perform well in the fight against ticks: Fitoverm, Akarin, Bicolom. They are used within the same time frames as indicated above, following the instructions. We must not forget that to achieve good results, manipulations must be carried out at a certain temperature.

Traditional methods

Experienced summer residents say that you can get rid of ticks with a hot shower. In early March, the branches are tied and watered with water at a temperature of about 70 degrees.

In addition, it is recommended to plant onions and garlic near the currants. A good effect can be achieved by preparing a garlic (200 g chopped garlic cloves + 10 l of water) or onion (300 g peel + 10 l water) infusion.

It is worth remembering that a black currant disease such as a mite is very dangerous. Therefore, you should under no circumstances ignore it unless you want to lose the entire bush.

Terry (reversion)

A viral disease transmitted by the kidney mite. The main danger of infection is crop mutation. If the bushes do not die, over time they become infertile.

To understand whether a plant is infected, you should take a closer look at the shape of the leaves. If the virus is present, they are elongated, deformed, with jagged edges, and acquire a purple tint. The number of veins decreases.

Changes also occur in flowers. They become narrow, the petals become elongated. To understand why currants are sick, you need to carefully observe the bush during the flowering period. Identified infected plants are eliminated, since it is impossible to completely destroy the virus.

To prevent the disease, you need to regularly feed the bushes, avoiding excess nitrogen in the soil. Treatment is carried out with Karbofos after harvesting. To do this, 60 g of the drug is diluted in 8 liters of water. To spray 1 bush, at least 1.5 liters of solution is required.

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Pests of red currants

Not all red currant pests can live on black currants. For example, the pale-legged sawfly prefers red currant leaves. Its pupae overwinter in the soil. The activity of adults begins in early spring, when the leaves have not yet blossomed.

Damage to red currants is caused by voracious larvae; they literally eat young leaves. Experienced gardeners advise how to treat currants in the fall against pests. In their opinion, when red currants are lightly infested with sawfly, fragrant infusions of tobacco and pepper are effective. Of the purchased drugs, Iskra is praised; it is used for extensive infection of the bush.

Gray rot

If the leaves of the currants have turned black and signs of wilting have appeared on the tops, a disease such as gray rot can be assumed. It is caused by the fungus Botrytis cinerea. Like many representatives of this class, microorganisms overwinter in fallen leaves, so to prevent the disease it is recommended to collect and burn them.

Gray rot develops in warm conditions with high humidity. You can recognize it by the following signs:

• the disease first affects young shoots, which gradually wither;
• the branches are covered with a gray coating;
• Dark spots appear on the leaves, which gradually expand.

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Gray mold is combated with antifungal drugs. Copper sulfate is considered the most effective remedy: 1 tsp. for 7-8 liters of water.

Another remedy is a soda solution with laundry soap. To prepare it, add 50 g of soap and soda to 10 liters of water and spray the plants.

Pests and how to get rid of them

In addition to various viral and fungal diseases, currants can become a victim of attacks by insect pests, which can damage all parts of the plant and lead to its complete death.

Bugs

Various bugs pose a particular danger to the plant, in particular the currant borer, the larvae of which eat the core of the branches. As a result of the negative influence of the beetle, the shoots dry out, the crop yield sharply decreases, the berries become smaller and become sluggish.

Parasitic beetles appear in early summer and lay eggs on branches after 7–10 days. The larvae, which hatch after two weeks, penetrate the trunk and eat away its contents. To destroy the pest and prevent its further development, all affected parts of the bush should be destroyed.

In case of massive damage to a currant plantation, it is recommended to spray the bushes with insecticides. Treatment of foliage with Actellik, which is carried out three weeks after flowering, is highly effective.

Among the bugs, currants can also be affected by the weevil, which emerges in early spring. Individuals eat the vegetative organs of buds and flowers, and later completely destroy the leaves and buds.

The only effective way to combat weevils is to treat shrubs with chemicals. Spraying is carried out in the bud breaking phase, using pyrethroid or neonicotinoid agents.

Caterpillars

Caterpillars can cause great harm to currants: leaf roller and glass beetle. The first is a small brown butterfly with small folded wings. Leafworm caterpillars are also brown in color.

Parasites feed on the leaves of the crop, causing them to curl, turn yellow and become covered with cobwebs. The caterpillars also eat buds, flowers, and berries. Biological products and insecticides are used for the treatment and prevention of leaf rollers.

The glasswort is a small butterfly with transparent wings that lays eggs in cracks in the bark or near the buds in midsummer. The caterpillars, which hatch from the eggs after two weeks, make hollow passages in the shoots, after which the branches dry out.

Unfortunately, identifying glass is quite difficult. As a rule, it is discovered in the second year, after the branches begin to dry out sharply before the berry ripening phase. To cure currants from the parasite, it is advised to cut out and burn all affected parts. Treatment with insecticides is carried out only in the first stages of the attack, before the caterpillar has time to penetrate inside the branches.

Did you know? The most common are white, red and black currants. However, today there are varieties of the crop with different colors of berries: yellow, green, orange and even purple.

Sawflies

Berry sawflies, or rather their larvae, which develop in the ovaries and feed on seeds, cause big problems for gardeners.

Under the influence of the larvae, currant fruits ripen quite early, but are absolutely not suitable for food. Moreover, if the berries are not collected on time, the larvae come out and you have to fight with them throughout the next season.

The fight against the parasite should include the following steps:

• Before currants bloom, spray with insecticidal preparations;
• before ripening, all infected fruits must be collected and destroyed;
• in autumn, clear the area of ​​vegetation and carefully dig up the soil;
• hill up the bushes and mulch them.

Currant fly

The currant fly or gall midge is a small mosquito-like insect that can damage all areas of the bush. In places where pest larvae develop, swellings are formed, which are called galls.

Three species of gall midges parasitize currants:

• leafy - affects the leaves of the bush;
• stem - develops on the stem;
• floral - lays eggs in flower ovaries.

Read more

How to deal with currant gall midge?

Symptoms of gall midge infestation of bushes are:

• yellowing and drying of foliage;
• formation of red spots on the leaf blades;
• leaf curling;
• inhibition of growth of young shoots;
• curling and falling of flowers.

All infected parts of the plant should be cut out and destroyed. In autumn, shrubs must be treated with Karbofos solution.

The best preventative measures against gall midges are:

• thinning of plantings;
• rejuvenation of bushes every 3 years;
• cultivation of land with tobacco water.

Useful care tips

To prevent the development of various ailments in currants and the appearance of pests, experienced gardeners advise following a few simple rules of care when growing crops:

• regularly visually inspect the bushes for the presence of parasites or signs of disease;
• carry out regular preventive spraying of the plant with folk remedies or special store-bought preparations;
• in the fall, clear the area of ​​vegetation, fallen leaves, and dry branches;
• all infected plants and their parts must be burned outside the site;
• strictly follow the moisture and fertilizing schemes for currants;
• carry out regular rejuvenating and sanitary pruning of shoots, preventing them from thickening;
• when growing crops on highly acidic soils, liming the soil;
• do not plant the crop in lowlands, otherwise it will suffer from fungal diseases from excess moisture;
• systematically loosen the soil.

We recommend reading how to care for blackcurrant bushes in early spring.
Protecting black currants from diseases and pests is quite simple. It is enough to follow the basic rules for caring for the plant, not to ignore the most important agrotechnical measures, and to begin the fight against diseases and parasites in a timely manner. If it is impossible to cure the bush, then it must be immediately cut out and burned outside the currant plantation.

Columnar rust

The disease is similar to the previous one and is also caused by a fungus that attacks the foliage. Small orange dots that look like pads form on the bottom of the leaves. Gradually they grow and turn into columns: they contain fungal spores. At the end of summer the foliage turns brown. If there are coniferous trees nearby, the disease can spread to them.

To prevent fungus, wood ash is placed under the bushes and regular fertilizing is carried out. If infection occurs, the plants are treated with a 1% solution of Bordeaux mixture (100 g per 10 l).

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Cytosporosis

A fungal disease, also called sharka, leading to the death of bark, branches, and subsequently entire bushes. It first affects old branches, and then young shoots, forming tubercles on them. Light, wide, round stripes appear on the leaves. With cytosporosis in currants, the berries ripen too quickly and have poor taste. In most cases they simply fall off.

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The fungus is carried by aphids. If there are plants in the garden that are affected by this pest, they must be sprayed with insecticides.

For processing, prepare a 3% solution of Bordeaux mixture. 300-500 g of quicklime is diluted with 10 liters of water and irrigated before flowering and after harvesting.

Scheme for treating currants and gooseberries against diseases