What to do if orange spots appear on currant leaves?

The appearance of orange spots on currant leaves clearly signals a problem. Usually this is how rust manifests itself, which can be of two types. The causative agents of the disease are pathogenic fungi. Certain environmental conditions favor the development of rust. To combat the disease, summer residents can use chemicals and folk remedies. Preventive measures are also of great importance.

Types of rust on currants

Usually currants are affected by two types of rust - columnar and goblet. Each of them has its own pathogen.

• Goblet

Goblet rust is caused by the mushroom Puccinia ribesii caricis Kleb from the class of Basidiomycetes. In addition to currants, the disease often affects gooseberries. Symptoms appear throughout the vegetative part of the plant. The fungus affects fresh shoots and leaves, flowers, berries. The disease greatly reduces the yield and weakens the bush itself. On currants, a pathogenic fungus develops in the spring. In summer, he changes owners and moves to various types of sedges.

The mycelium is spread by ecidiospores, which are carried by the wind over a considerable distance. At the end of summer, black pads containing teliospores are formed on the sedge, which hibernate here. In spring, the process of germination of teliospores begins and berry bushes become infected. The first symptoms begin to appear 10 days after the defeat.

• Columnar

Columnar rust is triggered by the basidiomycete Cronartium ribicola Dietr. The disease is widespread throughout Russia, especially in Siberia and the Far East, where there are cedar forests. In the summer cottage, the mycelium parasitizes on black and red currants, gooseberries.

Black currant is especially susceptible to columnar rust disease. The risk of the disease is increased if there is a cedar or pine forest nearby. On affected currant leaves, the first symptoms appear on the underside after about 2 weeks from the moment of infection.

Symptoms during infection

When infected with goblet rust, symptoms can appear on any part of the currant, but most of all manifestations are noticeable on the leaves. Bright orange spots appear on the top of the foliage. As the fungus develops, black dots form on the affected areas. On the lower surface of the leaves, yellow pads are formed, which later acquire the shape of goblets, which is reflected in the name of the disease.

With the progression of the lesion, the leaves begin to deform, and then completely fall off. The berries on such bushes do not develop correctly, acquire an ugly shape. In the future, their growth is suspended, the fruits begin to dry and fall off. The growth of young shoots slows down, the twigs become twisted and often freeze over in winter.

Columnar rust symptoms appear on plants in mid-summer. The upper surface of the leaves is covered with yellow spots. On the underside of the leaf blades, orange pads containing spores begin to form. Urediniospores, the fungus multiplies during the second half of the summer and spreads throughout the site. Warm and humid weather in the second half of July and August contributes to the intensive development of the disease. Such weather conditions reduce the spore germination period to 5 days.

Towards the end of summer, yellow-brown columns, consisting of basidia with basidiospores, are formed from the pads on the underside of the leaves in the presence of drip moisture.In autumn, basidiospores are carried by the wind in a circle and infect conifers growing nearby. For 1 season, the mushroom is capable of giving up to 4 generations. Affected currants lose their leaves ahead of time, which noticeably weakens the bush and reduces its resistance to frost.

Disease control methods

If any kind of rust is affected, currants prematurely shed their leaves; due to illness, flowers and ovaries may also fall off, which negatively affects productivity. In dry weather, red spots on currants rarely appear, but if it rains, the summer resident needs to be on his guard. The shrub must be regularly inspected to monitor its condition. If rust symptoms appear, urgent measures should be taken to suppress the fungus.

The use of drugs

If the signs of the disease were noticed late and the bush is severely affected, the use of industrial antifungal drugs will be required.

Popular fungicides for rust control:

• "Bordeaux liquid". An old, proven and effective remedy based on copper sulfate and calcium hydroxide. The composition is prepared by taking 100 g of both substances per 10 liters of water. The same remedy is used to prevent rust. The treatment is carried out three times. The first time the bushes are sprayed when buds bloom on the currants. Then, with an interval of 20 days, two more treatments are carried out.
• "Cuproxat". A copper-containing fungicide that effectively kills fungal spores. To prepare a spray solution, dissolve 50 ml of the drug in 10 liters of water.
• "Speed". The drug has a contact effect. It can also be used for prevention. The advantages of the fungicide are that it can be used at the time of bud and ovary formation on currants. The tool effectively fights the fungus at the initial stage. The solution is prepared from 4 ml of the drug per 10 l of water.
• "Topaz". The fungicide prevents the germination of spores of the fungus that causes rust, which leads to the attenuation of the disease. The advantages of the drug include the possibility of using it in rainy weather. "Topaz" remains effective at high air temperatures. To prepare a solution, take 10 liters of water and dilute 4 ml of fungicide in them.
• "Previkur". An effective broad-spectrum drug. Saves currants not only from rust, but also from root rot. In addition, it acts as a growth and immunity stimulant. Preparation of the solution requires dilution of 15 ml of fungicide in 10 liters of water. The composition must be thoroughly mixed.
• Fitosporin. Biological antifungal drug that also helps against bacterial infections. Safe for use during fruiting. Has a short decay period. A feature of the tool is that it must be used in twilight weather, in bright light it quickly decomposes, without having time to act. To obtain a solution, 5 g of "Fitosporin" are consumed per 10 liters of water.

Before you start spraying the bush, you must remove all affected shoots. Plant residues must be burned, otherwise the spores will end up on the ground and the currants will be re-infected.

Using folk remedies

Some summer residents are afraid of the use of chemicals, therefore they prefer to use folk remedies in their garden and vegetable garden to protect plants. It should be noted that the compositions prepared according to such recipes do not differ in speed and help only at the initial stage of the disease. They can also be used for prevention.

Suitable for rust treatment:

• Infusion of mullein. A bucket with a volume of 10 liters is 1/3 filled with slurry and poured to the top of the water. The composition must be mixed and left to infuse for 3 days. Before use, the infusion is diluted with water in a ratio of 1:10.
• Fermented milk product. You can use yogurt, kefir or whey.Any of these products is diluted with water in a ratio of 1:10, after which currants are sprayed.
• Infusion of garlic. Take 200 g of chopped garlic cloves, put in a 3-liter jar, fill with water and leave for 2-3 days. After that, the infusion is filtered and used for processing. By the way, it is useful to plant garlic near currants to scare off various harmful insects.
• Soda solution. The composition is prepared from 5 liters of water, 2 tbsp. spoons of soda and 2 tbsp. spoons of liquid soap. The mixture is thoroughly mixed until the components are completely dissolved, after which the bush is sprayed with the solution.

Processing should be carried out in dry, cloudy weather. On sunny days, the bushes are sprayed in the morning or in the evening once every 5-7 days. If the rain has washed away the applied composition, the spraying must be repeated.

Preventing rust

To reduce the likelihood of developing the disease, it is necessary to choose rust-resistant varieties for planting. Among black currants, these are:

• "Belarusian Sweet";
• "Black Veil";
• "Katyusha";
• "Temptation";
• "Kipiana".

There are also varieties of red currants that exhibit complex resistance to a number of diseases, including rust, for example:

• Chulkovskaya;
• "Victoria";
• "Faya is fertile."

In order for the currant bushes to remain healthy, it is necessary to promptly clear the area near the berry from weeds, especially sedges. In the summer, you should regularly loosen the soil, and dig it up in the spring and autumn. Fallen leaves are immediately burned. To strengthen the immunity of the shrub, it is required to apply phosphorus-potassium fertilizers according to the schedule. Currants need timely sanitary and anti-aging pruning. In early spring, it is recommended to scald the bushes with boiling water.

Do not panic when you notice orange spots on currant leaves. To defeat the disease, you can, most importantly, act urgently and systematically. Such a symptom cannot be ignored, otherwise you can lose a significant part of the crop, or even the shrub itself.