Every gardener wants to have a rich and healthy harvest of fruits and berries every year. However, on the path to achieving the cherished desire can arise diseases or pests. Sometimes you have to notice how various spots appear on the leaves of a plant. So, there are frequent cases of the formation of red spots on the leaves of red currants - what it is and how to treat this disease, let's understand together.
Description and photo damage
As a rule, spots appear in the summer. They can be dark red, burgundy, brown. At first they are small and may increase in size over time. Sometimes they resemble bloating. They can appear on both red and white currants, less often on black. Such a phenomenon is not the only trouble accompanying the plant and its owners. As a rule, he is accompanied by a change in the taste of the berries - on a more sour and chopping fruits. If you do not pay attention to the problem in time and do not begin to deal with it, it will spread to a wider area - entire branches can grow and dry out, and soon the whole shrub.
Did you know? Currant in Latin is called ribas. The origin of this name is interesting. After the Arab people conquered Spain in 711, its representatives did not find their favorite delicacy in the new lands - rhubarb, which the Arabs have added almost all dishes. Seeing the red berries, the taste of which remotely reminded them of rhubarb, they also began to call them ribas. So currant stuck this name.
Causes of
There are two reasons for the appearance of red spots on currant leaves:
- anthracnosis fungal disease;
- pest called gallic aphid.
Anthracnose
Anthracnose is raised by the mushroom Colletotrichum orbiculare. Its spores are spread by sediment, insects and wind. Favorable factors for the spread of the disease are warm, wet weather, high acidity in the soil, and potassium and phosphorus deficiency in the plant.
One of the most dangerous diseases of currants is toe rust.
The first symptom of the disease is the appearance of small dark red spots all over the leaf. As the disease progresses, the spots increase, they become more and more, and they merge into one huge spot. The leaf curls and dries. With a strong infection, spots can also be observed on shoots. Later cracks appear on them, they become brittle, and the plant eventually dies. Sometimes the fungus can even affect the fruit.
The manifestation of the disease occurs in the summer, starting in June. It reaches its peak in the second half of summer.
With what this red currant disease looks like, you had the opportunity to look at the photo, and how to carry out its treatment, we consider below.
Gallic aphid
Gallic or red head aphid is a sucking insect of miniature size - 2.2-2.5 mm in length. May have a different color - from yellow to brown. Like all other types of aphids, lives on the bottom of the leaf plate. Autumn lays eggs for wintering in the cracks of currant bark. Winged females fly out in the first weeks of summer. For the season, up to eight generations. In July, aphid goes from currants to weeds, and by autumn it returns to berry shrubs for egg-laying.
Symptoms of plant infection are galls - formations in the form of blisters on the upper part of the leaf plate. Since the aphids drink juice from the bushes with useful substances, in order to heal the wounds, special tissues begin to form in the plant. Therefore, growths are formed in the injury site.
Learn how to deal with other currant pests: aphids, ophthalmia, shield.
The most serious damage to aphids inflicts young shrubs. Favorable conditions for its active life are warm winters and hot summers without precipitations.
Did you know? There are many varieties of currants - about 150, the berries of which are painted in a variety of colors. In addition to the usual red, black and white currants, in nature there is also yellow, orange, purple and green. All of them are different in taste and content of nutrients.
Fight and treatment
As in the case of the appearance of most other diseases or parasites in plants, anthracnose and aphids can be fought with preventive measures, sparing folk remedies (decoctions and infusions of insecticidal plants, soap solutions) and chemical treatments. Consider those and other measures to combat red leaves on currants.
How to deal with aphids
Among the popular recipes to combat gall aphids the most effective are the following:
- Infusion of marigolds. Dry and chop the marigolds so that the raw material is about half a bucket (5 liters). Pour the flowers with a bucket of hot boiled water and leave them to infuse for 48 hours. Then add a 50 gram bar of laundry soap. Use for spraying leaves.
- Infusion of tomato tops with onion peels. 2 kg of tomato tops pour five liters of boiling water. Infuse the solution for two hours, then boil for three hours. Pass through cheesecloth. Dilute with water in a ratio of one to two. A pound of husk pour two liters of boiling water, insist 48 hours. Then add 2 liters of water and liquid soap as an adhesive. Infusion tops and infusion husk mix and use for spraying.
- Broth from tobacco dust. Half a cup of dust pour in a liter of water and boil for about 30 minutes. After removing from the stove add water to the original volume. Insist in a dark place for 24 hours. Then pass the broth through gauze to filter and add liquid soap (one teaspoon) or laundry soap (10-15 g). Use for spraying.
- Infusion of laundry soap. 300-400 g of soap diluted in 400 ml of water. Use for spraying or wiping the leaves, paying special attention to the bottom and the stems.
- The infusion of white mustard powder. The powder (10 g) is diluted with a liter of water and infused for 48 hours. Strain through. For spraying, take 200 ml of infusion and dilute with 800 ml of water.
- Infusion of red pepper. Cut a pound of pepper pods and place in an enamel container. Add a bucket of water and boil for one hour. Insist two or three days. Strain. For spraying use 150 ml of infusion, diluting them with a bucket of water.
Important! Treatment with folk remedies is carried out with an interval of seven to ten days at least two times. Spraying and wiping are carried out on days when there is no rain and no wind. If some time after the treatment there was precipitation, spraying is carried out again.Folk remedies are effective only with a slight defeat at the initial stage. If they didn’t help from red spots on the leaves, or if a massive aphid invasion is observed, then a better way than treating the red currant with chemical means, until it was invented.
Spraying against redness
With a slight defeat by harmful insects, biopreparations will help: "Fitoverm", "Biotlin", "Agravertin". The advantages of using these insecticides are that they do the least harm to the environment and are safe for humans.
If the strong spread of aphids could not be avoided, will have to use chemistry. Today, the drugs that most effectively recommended themselves in the fight against this insect are: Aktellik, Inta-vir, Konfidor, Calypso, Kinmiks, Aliot.
It must be remembered that the use of chemicals before harvesting is strictly prohibited. Carefully read the instructions to the drug, which indicates the minimum interval that must be observed between the processing chemicals and harvesting berries. Currant leaves, on which brown spots appeared as a result of anthracnose, must be removed and burned before treating plants with fungicides. If there is a strong infection, it is better to destroy the shrub.
For the treatment of anthracnose use: Oxyhom, Home, Abiga-Peak, Skor, Fundazol, Ridomil Gold MT, Profit Gold, etc.
Since mushrooms and insects can get used to the drugs, they should be alternated or changed. So prevention and control will be more effective.
Important! When spraying chemicals should strictly follow the instructions regarding the dosage and frequency of treatments, as well as personal safety measures: the body should be protected by a suit, eyes - glasses, nose and mouth - mask
Prevention
To prevent gall aphids, the following activities should be carried out:
- regularly remove weeds;
- conduct early spring preventive spraying Bordeaux liquid (3%) or other drugs of similar action;
- carry out insecticidal spraying before bud break, for example, with Iskra double effect, prophylactin, and nitrafen;
- plant in close proximity to currant bushes dill, parsley, cumin, cilantro, mustard in order to attract beneficial insects (ladybugs, earwigs, golden-eyed, hoverlings) that feed on pests;
- plant around currants strongly smelling plants that are able to scare away aphids, for example, chamomile, calendula, marigolds;
- destroy ant hills and destroy garden ants that are aphid vectors;
- before planting and planting a circle with hot water (+ 80-90 °), it will kill parasites after hibernation.
- early spring spraying Bordeaux liquid, Nitrafen, copper sulphate;
- before flowering, treat with immunostimulating preparations of the “Epin”, “Zircon”, “Immunocytophyte” type;
- properly fertilize shrubs, thereby increasing the sustainability of the culture;
- conduct sanitary pruning of shoots;
- in the fall, carefully remove plant residues and carry out deep digging around the stem;
- after harvest, spray with Bordeaux liquor;
- timely remove weeds;
- thin out thickened landing;
- choose varieties of currants that are resistant to this disease, for example, Victoria, Dutch red, Firstborn.
Did you know? For a person to satisfy his daily need for ascorbic acid, he needs to consume 35-40 pieces of black currant.Currant is a tasty and very healthy berry: in terms of ascorbic acid content, it has almost no equal among berries and fruits. The plant is unpretentious in the care and gives generous yields. However, this berry culture is subject to certain diseases and pest invasion. It is important to carry out preventive treatments in time and carry out timely treatment in order not to lose the crop, and indeed all berry plantings as a whole.