Diseases and pests of blackcurrant: characteristics and control
Experienced gardeners know that their favorite berry bushes can be attacked by a variety of diseases and pests. In order not to lose the crop and save the plant, you should constantly inspect it for warning signs. It is necessary to treat the bushes in a timely manner when a disease is detected, otherwise the gardener may lose the entire crop.
Common diseases
If the bushes seem healthy and strong, then this means that diseases have bypassed them. But with improper care for them, plants can become infected with some kind of virus and die.
There are a huge number of diseases that can affect a bush and leave its owner without useful and tasty berries. In order to find out in a timely manner about the infection of a plant, it is necessary to familiarize yourself with the symptoms of the most common diseases.
Below are the most famous blackcurrant diseases that can ruin the harvest in the country.
green mottling
During the period of bud break, faintly pronounced green dots can be seen on the leaf plates of the plant. In summer (June), they transform into watery strokes that stretch along the veins of the leaf.In some cases, instead of them, you can notice green spots that take up a large space on the sheet.
Such a disease cannot be cured, therefore, when the first signs appear, you need to uproot the bush and burn it outside the garden.
powdery mildew
Powdery mildew is a fungal disease that affects both shoots and other parts of the plant (berries, leaves). A gray coating appears on the affected areas, which becomes darker over time.
When the fungus multiplies, it takes the substances it needs from the plant. If the bush is not treated, then it will not develop and will soon die. The causative agent in winter is found on leaves in the soil, as well as on other plant debris. When the air temperature becomes positive, the fungus begins to multiply, spores move to the bush due to wind, insects and liquid drops.
Anthracnose
It is a fungal disease, the symptom of which is small red or brown spots on the leaf plate of the plant. In the center of it, dark tubercles are visible. The disease can affect fruits and leaves, which soon begin to wither and fall off. Most often, it settles on young shoots; in winter, spores are found on fallen leaves.
Gray rot
The fungus that causes this disease is located on the remains of plants in winter. The infection process begins in early summer, when the first wave of growth of young shoots ends. Shoots that grow back become sluggish. The disease begins its journey from the top of the site, gradually gaining momentum.
The gardener can recognize infected plants by the following symptom: when the weather becomes wet, the shoots are covered with a gray coating that resembles mold.If the leaf plates are infected, then large brown spots of an indefinite shape appear on them. After that they crack. Quite often, the disease can be seen in too dense plantings.
columnar rust
There are yellow spots on top of the leaf plate, and orange-yellow outgrowths on the bottom, where the spores are located. After a while, yellow hairs form there. This disease is caused by a fungus.
Currant bushes are quite sensitive to this scourge, so if any plant next to them is infected with a similar disease, then you need to get rid of it.
goblet rust
In spring, the leaf plates of the bush are covered with dark dots from above, and from below - with large yellow "pads" that have goblet-shaped depressions. In winter, the spores of the fungus are in the sedge. This herb can grow anywhere, so the plant can easily become infected with the disease. In the spring, spores are transferred to the leaves of the culture, which contributes to the deformation of the berries in the future.
Soon the fruits begin to dry out, and then completely crumble. If the disease is not treated, then it causes a low yield of the bush.
Septoria
Small gray spots with a gray border appear on the leaf plates. After some time, growths can be seen on the bush, resembling small balls in which fungus spores are located.
marginal necrosis
The disease begins to manifest itself if there is a large amount of chlorine in the soil. In August, the edges of the leaf plates become ash-gray. They look like a dry streak, which is quite sharply different from the healthy parts of the plant.The symptoms of the disease are similar to the signs of potassium starvation, but there is one difference: the border between the affected and healthy tissue is distinct. If the site is affected recently, then it is paler than other areas.
Non-cryogenic shrinkage
If the gardener takes care of the bushes poorly, then they can get sick with nectrium drying. This disease is fungal and can affect any part of the plant.
Orange dots appear on the branches. At first they are small, but over time their size will only grow. After a certain period of time, brown tubercles will appear instead of them. If you treat the disease carelessly and do not treat it, then the young shoots will dry up.
If the leaf plates turn yellow, then the bushes where they are located should be cut off to get rid of the damaged parts - in this case, the disease will not be able to progress.
Terry
Growers can tell if a bush is affected by terry before the process becomes irreversible. Each of the sections of the culture ceases to exude a characteristic currant smell. In the spring (May), when the leaves are loose and the plant begins to bloom, you can also see that the bush is affected. Leaf plates bloom later than they should. They are three-bladed, although they should be five-bladed.
On the edges are large rare teeth. Young leaves become small, dark green, thickened veins. In the future, such leaf plates cease to develop.
The disease can also be determined by the structure of the flowers. In the normal state, their petals grow together, are white and round in shape. Affected bushes have flowers, the petals of which are divided and have a purple color.Stamens, pistil and petals change shape: instead, you can see the scales, which are shaped like tentacles stretching forward.
The flower clusters become longer, dark pink or purple. Of these flowers, fruits most often do not set, but if they are, they are small berries of ugly shapes. Infected plants bloom late.
striped mosaic
This is a virus that can be transmitted to a bush through the sap of an infected plant, aphids, mites, or garden tools when a gardener cuts diseased and healthy bushes. If the plant suffers from a striped mosaic, then bright yellow patterns can be observed around the veins of the leaf plates. It is useless to treat such a disease, so it is worth getting rid of the bush and making sure that the particles of the roots do not remain in the soil. Then it is burned.
Pests
In addition to diseases, the plant can be attacked by various pests that feed on the substances necessary for the development of bushes, as well as leaves or other parts of the plant. You need to be prepared for the fact that for a good harvest you will have to deal with some insects.
- kidney mites - These are small, almost invisible pests, having a length of 0.2-0.4 mm. They drink the juice of the plant, because of which the leaves do not receive nutrients and begin to dry. The most striking sign of the attack of this insect is too swollen kidneys. Inside them are vitreous eggs, from which pests subsequently appear.
- Spider mite. It has a small size (0.3-0.6 mm), located at the bottom of the leaf plates. Such an insect drinks juice from young shoots and leaves of a bush.If the plant is attacked by spider mites, then yellow dots appear on its leaves. Then they will become marbled, completely yellow and dry. If you do not fight the pest, then a small, thin web will appear on the bush.
- Berry sawyer. When the insect grows, it has a length of 3-4 mm. The color of the larvae is off-white, they are located in the ovaries, feed on the seeds of the plant. If the berries grow too much, quickly stain and become ribbed, then this means that the bush was attacked by berry sawflies.
- Kidney moth - This is a medium sized butterfly with a yellow-brown color. Rarely attacks blackcurrant, but sometimes hibernates under the bark or at the base of the plant. Then a caterpillar appears on the culture and feeds on what it finds in the kidneys. After the bush fades, the caterpillar transforms into a butterfly and leaves eggs in the berries.
- Currant aphid. If the upper leaves begin to curl, red swollen spots appear on them, and the shoots are twisted, it means that aphids have settled on the plant. Insect colonies are located at the bottom of the leaves, but they can also be located on the shoots - usually there the aphid waits out the cold season.
- Ognevka. When the bush begins to bloom, insects (butterflies) leave their eggs in the inflorescence of the plant. Caterpillars feed on berries and leaves, braid these areas with cobwebs. One insect can eat 10-15 fruits.
- Glass case. In the spring, when pruning is carried out, you can see if the bush is affected by insects. Caterpillars are located inside the shoots of the plant, due to which wormholes appear. They eat the inner part of the shoot, make many moves in it, because of which the branches dry, do not grow and subsequently die.
The first winter, the insect is inside the branches of the plant. In March, such branches are extremely visible, as berries and flowers dry on it. Then the branch itself begins to dry out.
If you carefully cut this branch with a pruner, you can see the black core. The branch should be cut off gradually until clean wood that has not been spoiled by pests becomes visible. Affected pieces of the branch are burned.
If the gardener is interested in what the pest looks like, he will be able to find a glass case among these scraps. It has a medium size and white color (beige head). If the gardener cut the stem to the ground and saw only a black core, then this means that the caterpillar is no longer in the branch - it came out of it in order to subsequently pupate and turn into an adult.
Treatment
After the gardener has learned that the plant is affected by some kind of disease, the following measures must be taken:
- collect affected leaves, ovaries;
- get rid of diseased branches and ends of shoots by cutting;
- carefully dig the soil under the plants;
- the affected parts collected earlier should be disposed of (burned or buried in the soil for one meter).
If the disease that has affected the bush is viral, it is necessary to destroy the infected plants and planting material, otherwise the infection may spread to other bushes.
There are two options for the treatment of various diseases and plant damage by insects. Some gardeners prefer folk remedies, as they trust them more than chemicals. Many people like to use chemical products, as most often they really help get rid of the problem. Both options are successful, so it is worth considering each of them.
Folk remedies
There are folk remedies that you can make yourself. The methods are effective and will help rid the plant of insects and diseases.
- Spider mites afraid of mustard infusion. 200 g of mustard powder is placed in 10 liters of water, the product is infused for 10-12 hours. After which it is filtered. The bush should be sprayed with infusion.
- From aphid eggs and bud mites can be disposed of with boiled water. It should be sprayed on the plant before the buds open. You can also do it in November. Garlic water also allows gardeners not to be afraid of these insects. It is necessary to take 100 g of garlic, chop it and place it in 10 liters of water.
- Aphid does not like a pungent smell, so you can use an infusion of onion peel (200 g of onion peel pour 10 liters of water and insist for 5 days) or a soap solution. For a soap solution, 300 g of 72 percent laundry soap must be divided into 5 parts (50 g each), grated (preferably finely) and dissolved in 3 liters of water. The product is infused for 24 hours, sometimes stirred. For 2 liters of water, 300 g of ash is required. The product must be boiled for 20 minutes, left to cool. Then it is filtered. The soap solution prepared earlier is mixed with 2 liters of ash solution, the total volume is brought to 10 liters. This tool is considered extremely effective, they need to spray the bush.
To combat the glass case, you must use the tools described below.
- A kilogram of wormwood (a little faded) is poured into 2-3 liters of warm liquid, boiled over low heat for 15 minutes. Then left for 5-6 hours. The volume needs to be brought up to 10 liters, they process the bush.
- Carefully chop a kilogram of green tops of potatoes with a knife, pour water (10 l), leave for 4-5 hours.
- Insects can be caught with fruit syrups in the summer. You need to constantly check them in order to destroy the pests that are caught.
- The plant is sprayed with a solution or infusion that has a very strong pronounced odor. You can use needles, tansy, stepsons of tomato. Sometimes branches of needles are laid out among the crops.
Getting rid of the attacks of the berry sawfly is quite simple:
- infected berries are collected and destroyed;
- the soil around the bushes should be dug up, the leaves must be disposed of;
- the bushes are hilled, the soil is mulched with compost or peat (layer thickness - 8 cm);
- after the plant has faded, it is necessary to carry out its disintegration.
There are many folk remedies for getting rid of glass rust. Most often, gardeners use the infusion of tobacco dust. To do this, 200 g of tobacco dust must be left to infuse for 3 days in 2 liters of water. A glass of garlic cloves is poured with 2 liters of hot water and also infused for 3 days, after which the ingredients are mixed, laundry soap and a small amount of hot pepper are added to the product. This solution should be sprayed on the plant before the buds open.
Iodine will help to defeat powdery mildew. To do this, 10 mg of a five percent solution of iodine should be diluted in 10 liters of water. Spray plants should be very carefully, several times (interval - 10 days). It is highly effective if the disease has appeared recently.
There are also several other ways.
- Place two tablespoons of mustard powder in 10 liters of hot water, leave for 1-1.5 hours. When the infusion has completely cooled, you need to process the affected bush.
- Prepare the strongest infusion of potassium permanganate.The plant should be treated with it 3 times (interval - 5 days).
- A kilogram of ash is placed in 10 liters of hot water, infused for 1-2 days. It is filtered, 50 g of soap is added to the product. Sick plants are sprayed. The treatment must be repeated in a week. The remedy is used only at the beginning of the disease.
If the plant was struck by gray rot, then it is worth treating it and the soil under it with ash infusion. This must be done before the bush begins to bloom, as well as after flowering and after harvesting the fruits. For this, 3 kg of ash are diluted in 10 liters of liquid. You can also use soda ash and soap (50 g of soda, 50 g of soap, 10 l of water) or an emulsion with soap and copper (150 g of soap, 20 g of copper sulfate, 10 l of water).
Any decoction or infusion should be used only in cloudy weather, morning or evening - this will save the plants from the possibility of getting burned.
Chemicals
Powdery mildew is a serious disease that is extremely difficult to get rid of. If the gardener notices the first signs of the disease, it is necessary to use copper-containing preparations. The most effective are "Khom" and "Ordan". It is necessary to spray the affected areas. Before you start spraying, you should get rid of infected leaves, shoots and fruits.
Below are a few more worthy drugs.
- Landings need to be processed colloidal sulfur or products based on it ("Jet", "Thiovit"). Processing is carried out a few days before the fruit is harvested, since colloidal sulfur is not capable of harming human health.
- Tilt, Skor, Quadris. Bushes should be treated with these preparations 4 times.The first spraying is done after the leaves have blossomed, the second - after the flowering period, the third - after harvesting, then wait 2 weeks and make the fourth treatment. If the summer is damp, you need to process the plant a fifth time after 17 days.
The diseased parts of the plant affected by anthracnose should be removed by hand. Then it is worth treating the bush 4 times with products that contain copper. The first time you need to spray the plant before the buds open. Soon 3 more sprays are made (interval - 10-14 days). Fallen leaves and plant remains must be removed. The aisles of the bush must be carefully weeded.
If the disease has just begun to manifest itself, then you can use the means "Fitosporin" and "Alirin B". These drugs are safe for people - a few days after spraying, you can pick berries. In autumn, the soil on which the bushes grow must be treated with Trichoderma.
If the plant is infected with rust, then you should first get rid of the affected leaf plates. In March or April, before the buds on the bush open, you need to treat it with a three percent "Bordeaux mixture", "Hom" or "Nitrafen" (the latter drug is extremely effective, but difficult to find). When the buds open, the currants are treated with one percent solutions of these agents. Branches need to be sprayed. "Nitrafen" can be watered around the perimeter of the plants. If the symptoms of rust have appeared recently, then you should use Topaz, Skor or Fitosporin.
Septoria is a dangerous disease, but the plant will be easily saved by spraying "Soon". The bush should be processed 2 times: when the buds form and after it stops blooming.
In order for the plant not to be affected by this disease, it should be fed with mineral fertilizers - in this case, the gardener will save himself from fighting it and get a good harvest.
If the bush was attacked by bud mites, you need to carefully cut off the buds affected by insects, capturing the shoot. After that, they should be burned. Then the plant is treated with products that contain sulfur, for example, with a variety of acaricides, such as Nissoran or Apollo. It is worth spraying the bushes after picking berries.
When a bush is infected with spider mites, it is necessary to treat them before the start of the growing season with Trichlormetafos-3. If the insects have not abandoned their attempts to harm the plant, then it is worth repeating the treatment before and after flowering.
If the symptoms of berry sawfly attacks were noticed by the gardener last season, it is necessary to treat with Karbofos before the flowering period. If the plant was processed after it, then its fruits should not be used as food.
To get rid of aphids, the plant is treated with Fufanon, Decis, Aktara, Insector, Iskra, Intoy-Ts-M, Intoy-Vir or Kinmiks. These products are easy to acquire, they are extremely effective, and have affordable prices.
Before use, it is better to read the instructions so as not to harm the bushes.
A one-percent "Bordeaux" liquid saves from infection with columnar rust, which needs to be sprayed on the bushes 3 times: when the leaves bloom, the buds separate and after the flowering period. If the disease progresses, then you need to do another, fourth treatment 10 days after the third. To prevent the disease from infecting other plants, it is necessary to rake up the infected fallen leaves in a timely manner and burn them.
In autumn, the tops affected by gray rot must be cut out and then burned. The soil on which the bush grows should be dug up to close up the fallen fruits and leaf blades. In March, before the buds begin to bloom, the bushes are sprayed with boiling water (60-65 degrees).
There are also incurable diseases that cannot be cured with both folk remedies and chemical preparations. Among them, the most common is terry. If the disease has affected the plant, then it should be urgently removed and burned. If this is not done, it can infect all the bushes nearby. On the soil under the infected plants, you can not plant new bushes for 5 years. Fighting the virus is useless.
Prevention
Every gardener wants his culture to be healthy, bear a large number of fruits and please him with proper development. To do this, you should properly care for her, otherwise she may bring a poor harvest or even die.
- Seedlings must be planted with a deepening of the neck of the root by 3-5 cm. The shoots should be cut so that there are several buds above the soil.
- It is important to water and mulch the ground in a timely manner using peat, humus or compost - this will help protect the plant from many diseases.
- If the bush has been growing for more than 7 years, it must be replaced with a young plant.
- Every year you need to properly cut the bushes. A few of the best basal shoots are left, the gardener needs to get rid of the rest.
- Some gardeners use fresh manure for planting plants. No need to make a similar mistake - it is better to apply nitrogen fertilizers. The most effective top dressing for currants is humus and wood ash. Funds must be paid for digging.
- In September-October, it is important to collect leaves, get rid of dry berries on the bushes, and also dig aisles.
- Before severe frosts begin, it is important to carefully inspect and clean the bark that has peeled off. Then it should be burned.
- Before the juice begins to move through the plant, shoots that are old or affected by mites, larvae of other pests or powdery mildew should be cut. Treat the cut sites with a 1% solution of copper sulphate and cover with a garden pitch.
- The plant will be more resistant to powdery mildew if wood ash is added under it. This is an extremely good combined phosphorus-potassium fertilizer, which will allow currants not to be afraid of this disease.
- The main preventive measure is the purchase of healthy planting material, which is made by certified manufacturers. You can also choose varieties that are resistant to many diseases and pests.
It is important to constantly treat the bushes with plant or chemical preparations at the necessary periods - this will create a healthy phytosanitary background of the site, which contributes to a large, high-quality crop.
Spraying the bushes with any means will help make them more resistant to any diseases and insects. But if you do it wrong, you can harm the plant, so there are recommendations that can save currants from many problems.
- Stuffy and warm weather is not suitable for processing - it is important to spray in the cool time of the day. If the temperature is warm, pests and parasites will multiply more actively.
- It is better to carry out several procedures, the interval between which should be 10-14 days.
- Before starting the process, it is worth getting rid of infected or old parts of the plant. Items that have been removed should be destroyed so that they do not harm other crops.
In order for the immunity of the bush to be strong and withstand the attacks of various diseases, it is necessary to use organic and mineral fertilizers - such compounds will give the plants strength and contribute to a decent harvest. In summer, it is important to constantly make the ground under the bushes loose. Loosening is carried out very carefully so as not to harm the root system of the plant, which is most often quite close to the soil surface.
If the grower does not want to frequently loosen the soil, then a small layer of organic mulch (approximately 5 cm) is laid under the crop. Currant does not like heat, so it is better to plant it where there is shading.
In spring, immediately after the snow melts, the root system of the crop begins to actively develop and grow - it needs nutrition and moisture. When the weather is dry, the bushes should be watered once every 5 days. Water should be warmed up a little, as too cold liquid will only harm the plant.
There are people who water currants from above, which is a big mistake, because if you constantly moisten the leaf plates, the plant can get powdery mildew.
It is extremely important to pay attention to the first symptoms of diseases or pest attacks in a timely manner. If the leaves are twisted, have an unnatural color for them, the fruits dry up, and the plant itself does not develop as it should, you should try to find signs of any disease in order to immediately cure the plant. If you treat this carelessly, do not take care of the crop and do not treat the affected areas, the yield of the bush will decrease, and then the plant may die.
A gardener who tries to take care of currants, acquires fertilizers and means for the prevention of diseases, will receive many tasty, healthy fruits and a lot of positive emotions from growing such a crop. Careful care guarantees resistance to many diseases and parasites.
For information on how to protect blackcurrant from diseases and pests, see the following video.