Content
Currant septoria blight is a fungal disease that spreads well in humid and warm environments. It manifests itself as brown spots, due to which the foliage becomes deformed, dries out and falls off. Treatment is carried out using chemical and folk methods. Special agrotechnical measures are also used.
Causes of currant septoria blight
Currant septoria blight is a fungal infectious disease. The pathology develops gradually, passing through two stages - primary (early spring) and mass (mid-summer).
Fungi produce sclerotia, which overwinter on dead parts of plants or in the surface layer of soil. In spring, they form ascospores that infect young currant leaves. Mass distribution is observed in July and August, when the bushes produce berries. At this stage, conidia appear - fruiting bodies with black dots in the center.
The main causes of septoria are:
- high humidity;
- warm weather;
- contaminated water;
- spread by wind;
- too tight fit;
- adverse effects of weather factors (drought, temperature changes, severe frosts);
- violation of watering norms.
The fungus actively spreads in the temperature range from 20 to 25 degrees. Moreover, it can germinate even at +9 °C, and the maximum permissible temperature is +28 °C.
How it manifests itself
Determining septoria currant blight is quite simple. It manifests itself with the following signs: brown spots on the leaves. They can be round or in the form of a regular polygon. Gradually they increase in size and merge with each other. The color of the spots is first brown, then white with brownish edges.
In the center of areas affected by septoria, black dots appear - these are pycnidia. By their presence, currant septoria can be unambiguously determined. Moreover, they appear only in wet weather conditions. If the summer is dry, the dots do not form. Because the spots on the foliage gradually lighten, the disease is also called “white spot.”
A currant leaf affected by septoria blight can be easily seen by its spotting.
How dangerous is septoria
Like any fungal disease, septoria poses a serious danger to black and other types of currants:
- leaves become deformed, dry out and fall off;
- the bark becomes brown;
- the yield decreases sharply - up to 50%, and it may not recover even the next season;
- if the damage is severe, the bush dies;
- since the pathology is infectious, it applies to both currants and other plantings.
Therefore, every gardener needs to learn how to correctly identify the signs of septoria and carry out treatment when the first symptoms appear.
Treatment of blackcurrant septoria
To treat septoria, mainly chemical preparations are used - systemic, contact type fungicides. Along with them, folk methods are also used. They are especially effective in the early stages. Agrotechnical practices also help. All the described means are used in combination - thanks to this, septoria can be dealt with quite quickly.
Agrotechnical measures
To prevent the spread of infection, it is necessary to organize proper care for currant bushes:
- In early spring, before sap flow begins, old, diseased, weakened branches are removed.
- In autumn, all leaves, shoots and other debris are removed from the tree trunk circle. They are taken away and burned.
- The bushes are watered periodically, but in moderation, making sure that the soil is not too wet.
- After watering, the soil is loosened. It is also dug up between rows to a depth of 5-10 cm. At the same time, weeds are destroyed.
- Another agrotechnical measure to combat septoria is the cultivation of currant varieties with good immunity.
The most resistant varieties include:
- Ant;
- Pearl;
- Shmyrev;
- Crane;
- Kipiana;
- Minai.
Ant is one of the blackcurrant varieties resistant to septoria.
There are also moderately resistant varieties, for example, Narodnaya, Zorya Galitskaya, Orlovskaya, Gamma, Augustinka. But some representatives of currants have practically no immunity to septoria - these are Exotic, Sweet Brown and Vigorous.
Chemicals
Black currant septoria can be treated with special preparations - fungicides. The most effective include:
- "Chomecin" (also called "Cuprozan") is a drug based on zineb and copper oxychloride.Treatment is carried out before flowering, as well as after harvesting. At other times, spraying is prohibited, since oxychloride accumulates in the body and poses a health hazard.
- “Fthalan” is a powdery drug that is poorly soluble in water. To treat currants against septoria blight, prepare a suspension with a concentration of 0.6%. Low toxicity for humans and animals. Also used to treat various types of spotting and powdery mildew.
- "Kaptan" is an insoluble yellow powder. For treatment against septoria, a suspension of 0.6% concentration is also prepared. Used as an alternative to Bordeaux mixture.
- "Ridomil" is an effective fungicide, used mainly for the prevention of septoria, but not for treatment. It is important to use a mask and goggles during processing.
- "Bayleton" is a drug against septoria and other fungal diseases. Compatible with many other products. Gives the first result within a day, the period of protective action is up to four weeks.
- "Abiga-Peak" is a good remedy that destroys pathogenic fungi and bacteria. Does not pose a danger to plants and soil, does not penetrate into fruits. It adheres well to the surface of the leaves.
- Vitriol (copper, iron) are available fungicides that help cope with septoria currant blight. Protect bushes for 20-30 days after treatment.
"Abiga-Peak" eliminates both fungal and bacterial diseases
Folk remedies
Folk remedies are effective in the early stages of currant septoria. As a rule, they are used in combination with chemicals.The most effective recipes include the following:
- Table salt solution – 200 g per 10 l. It is sprayed on bushes along with foliage and fruits after removing shoots affected by septoria.
- Garlic infusion - chop the cloves (from four heads), pour warm water (2 l). Leave in a dark place for 24 hours. It is necessary to strain and bring to a total volume of 10 liters. Add 1 g of potassium permanganate and treat the currant bushes.
- A solution of pharmaceutical iodine (20 drops) with whey or milk (1 l) per 10 l of water. All components are mixed and treatments are carried out (once every seven days). It is very important not to disturb the concentration of iodine - otherwise signs of burn will appear on the currant leaves.
- Collect horsetail, chop it, measure out 300 g and cook for half an hour over low heat in 1 liter of water. Then filter and bring to a total volume of 10 liters. Treatment is carried out once a month.
- Take a piece of laundry soap, grind it on a grater, dissolve it in 10 liters of warm water and process it. You can also add 200-250 g of wood ash.
Prevention
Coping with the consequences of septoria of black and other types of currants is not always easy. Sometimes bushes die, they can also infect gooseberries, lilacs, peonies, roses, phlox and many other fruit and ornamental plants. To prevent negative consequences, experienced gardeners recommend following basic preventive measures:
- Treatment with copper-containing fungicides in early spring.
- Compliance with the minimum planting interval is 50-70 cm.
- Destruction of pruned branches and fallen leaves in the fall.
- Regular application of fertilizers.
- The right shelter for the winter, especially in the Urals, Siberia, and northern regions.
- Preventative fertilizers for currants against septoria - before flowering and after harvesting, water with a solution of manganese sulfate (0.1%), and a month after picking the berries - with a solution of potassium salt (1%).
- Weeding, loosening the soil, digging in the fall.
Regular pruning and preventive treatments reliably protect plants from disease
Conclusion
Currant septoria is a rather dangerous disease that affects bushes at different ages. It is quite simple to determine the pathology by the spots on the leaves. At the first detection of symptoms, it is necessary to begin treatment, otherwise you can lose not only the crop, but also the shrub itself.
