Content
Chlorosis of currant leaves is a complex of diseases, the causes of which may be associated with infections or metabolic disorders. As a rule, pathology occurs due to improper care, when plants clearly lack nitrogen, iron, magnesium or other elements. For treatment, several feedings are used. Moreover, it is better to use highly specialized compounds rather than complex ones. It is also possible to use folk remedies.
Causes of currant chlorosis
There are two types of chlorosis - infectious and non-infectious. The first is associated with exposure to fungi, viruses, bacteria and other pathogenic microorganisms. This is a dangerous disease that quickly infects currant bushes and neighboring plants.
Non-infectious chlorosis is associated with a lack of nutrients, such as nitrogen, phosphorus or potassium. Its main reasons are:
- infertile, depleted soil;
- root damage;
- unbalanced application of fertilizers (lack or excess, irregular feeding);
- increased soil moisture;
- absence of stones, sand and other drainage;
- too acidic or, conversely, alkaline environment.
Thus, currant bushes suffer from chlorosis due to improper care.
Symptoms of occurrence
Chlorosis of currants and other plants is quite easy to determine visually. The disease is always accompanied by a change in the color of the leaves, and often the stems. They become yellow, purple, and covered in spots. The main stages of development are:
- First, the currant leaves lose their classic bright green color.
- They begin to turn yellow and become pale.
- They may then develop brown, brown, or purple spots, depending on the specific type of chlorosis.
- Currant foliage and shoots die.
- The bushes lag behind in development, look weakened, and bear fruit poorly.
Important! Chlorosis can develop cyclically throughout the season.
For example, it disappears in the spring and then appears in the summer, after which it disappears again by early autumn. Therefore, when the described symptoms appear, it is necessary to feed the bushes with fertilizers.
After some time, the signs of the disease disappear and then reappear
To determine blackcurrant chlorosis, as in the photo, you need to know about the symptoms of a deficiency of a particular microelement:
- Iron chlorosis is more common than others. It is almost always observed on calcareous soils with an alkaline reaction. It manifests itself as a uniform yellowing of the entire leaf blade, with the exception of the veins, which retain a green color.
- Magnesium - most often develops on light soils - sandy loam and sandy soils. It is similar to iron chlorosis, in which the color of the currant leaf changes not only to yellow, but also to red or orange. Old foliage is affected first, then young foliage.
- Sulfur occurs in highly acidic soils.Young currant leaves turn yellow, and the process begins with the veins.
- Nitrogen - white or yellow veins appear on the leaves. The provoking factor is acidified soil. Nitrogen deficiency should be eliminated as quickly as possible, since due to this type of chlorosis, currants grow slowly, which will affect the yield.
- Zinc – orange or yellow spots appear on old currant leaves. At the same time, signs of nitrogen chlorosis are often observed.
- Calcium - a rare variety, leads to yellowing of the foliage over the entire area. As a result, the ovaries stop growing and fall off, and rot appears on the currant berries. The disease often appears in sandy soil conditions.
Why is chlorosis dangerous?
Any type of chlorosis poses a serious threat to currants. Due to the development of the disease, natural metabolic processes in the plant, including photosynthesis, are disrupted. Because of this, the foliage dies, falls off, and the bush slowly fades.
First, young shoots and leaves are affected, then the disease spreads to old ones. At the same time, the ovaries fall off, which has a bad effect on the yield. Even if the currant berries are formed, they will be small and irregular in shape. They often ripen with a delay.
Another dangerous consequence of chlorosis is a weakened immune system, which can cause the bush to suffer from diseases and pests. In addition, winter hardiness decreases; the plant may die during severe frosts or against the background of temperature changes.
How to deal with chlorosis of black and red currant leaves
The fight against chlorosis of black and other types of currants is carried out using different means. The most effective option is to use ready-made complex fertilizers with a balanced composition. You can also use folk remedies. In order to prevent the development of currant chlorosis, it is important to carry out basic agrotechnical measures (pruning, loosening, preventive treatments, etc.).
Chemicals
Chlorosis can be eliminated fairly quickly with the help of chemicals. It is best not to use organics and complex compounds, as they can only accelerate the development of pathologies. You should use fertilizers that contain exactly the necessary microelements, for example:
- "Agricola".
- "Iron chelate".
- "Ferovit".
- "Ferrylene"
"Agricola" is a powder that contains nitrogen, phosphorus and potassium (approximate ratio 1:1:2), as well as various trace elements. To treat currant chlorosis, it should be applied according to the instructions. First, the powder is dissolved in water and then poured under the root.
The product not only enriches the soil with nutrients, but also stimulates the ripening of the crop. The drug is applied twice a season - in early and mid-spring with an interval of 2-3 weeks.
Iron chelate is used to treat iron chlorosis
Antichlorosin is produced in the form of a solution of 10% concentration. They are used both for watering the soil and for treating plants. At the same time, application to the soil is more effective. During the season, up to three sprayings are carried out at intervals of two weeks. For each adult currant bush, use up to 25 liters of working solution.
"Ferovit" is a complex remedy for eliminating iron deficiency in the soil. It is the same iron chelate, but here the composition differs in the presence of nitrogen compounds.Apply in any month of the season, including shortly before harvest. Does not affect the taste of currants.
Ferrylene is a chelated iron used to prevent currant chlorosis. The standard dosage is 1 g per 2 liters of water. The drug must be stored in a dark place, since organic complexes are quickly destroyed when exposed to sunlight.
Traditional methods
You can also use folk remedies to treat and prevent currant chlorosis:
- Tobacco dust, which is used against pests, contains a lot of magnesium, iron and phosphorus. It is infused in water and sprayed.
- Wood ash contains a rich complex of phosphorus, potassium and trace elements. To process it, it is infused in water and sprayed on the bushes. The powder can also be covered during planting.
- Water after washing cereals is a preventative against chlorosis. It does not contain many valuable elements, so it is used undiluted.
- Onion decoction - 50 g of onion peel per 10 liters of water. The liquid is boiled for 5 minutes and infused for three hours. Used both for irrigation and foliar treatments.
Agrotechnical measures
Agrotechnical measures also help in the fight against chlorosis. First of all, you need to carefully choose a place to plant currants. It should be sunny and protected from winds, as well as from stagnation of rain and melt water.
To avoid chlorosis, currant seedlings should be planted on light, fertile soil with a loose structure. Loam with a slightly acidic or neutral pH of 5.5 to 7.0 is optimal.
During the growing process, it is very important to periodically prune - in early spring or late autumn. The soil is loosened so that the roots have constant access to oxygen. Deformed and dried ovaries are pinched as necessary.
If you regularly fertilize, the bushes will delight you with a high yield.
Preventive measures
Preventing currant chlorosis is always easier than eliminating its consequences. For prevention purposes, it is recommended to take the following measures:
- In the spring, the bushes are treated with Bordeaux mixture or other preparations.
- Regularly feed currants. In the spring, nitrogen compounds are given; during the budding period, emphasis is placed on superphosphate and potassium sulfate.
- Do not add organic matter in excess quantities.
- In the fall, be sure to clear the tree trunk circle of fallen leaves and other plant debris.
- For the winter in frosty regions, they must make a shelter. The tree trunk circle is mulched with straw, hay, peat and other materials. After pruning, the branches are tied in groups of 3-4 pieces and then laid on a “cushion”. The top is covered with dense agrofibre.
Conclusion
Chlorosis of currant leaves is quite dangerous, since a chronic deficiency of one or another element can lead to the death of the bush. Infectious forms of the disease also carry serious risks - the pathology can spread to neighboring plants. Therefore, when the first signs of chlorosis are detected, it is necessary to immediately determine the cause and treat with the appropriate drug.
