Apple scab is a fungal disease. It is important not to let it develop at the very beginning, to decide as soon as scab appears on the apple tree how to fight it.
Otherwise, by autumn, instead of beautiful, juicy and tasty apples, small, deformed fruits will hang on the tree, which do not last long and have an unpleasant taste.
One of the most serious tasks of a gardener is how to save an apple tree from scab.
Description of scab on apple trees
Literally everyone can determine the presence of scab on trees: spots (on leaves, fruits) immediately catch the eye, which at the very beginning of their development have a yellow-green color, and later turn black and often crack. The causative agent of apple scab is a marsupial-type fungus, namely Venturia inaequalis. This fungus usually affects leaf blades, as well as ovaries and, of course, fruits. The fungus is most active in wet years and periods of the season, when there are heavy rains, fogs, or damp weather for a long period.
Eucharis leaves turn yellow and die
Cineraria: planting and care in open ground
How to treat grapes in the fall before covering
Usually, the scab fungus gets on the bark and shoots of trees in early spring; with the help of the mucous membrane, it literally clings to the shoots and immediately begins to develop, sometimes quite actively.
The first noticeable signs of the appearance of fungus can usually be observed during the flowering period of the apple tree, which often occurs in the month of May. Often this period is characterized by heavy rainfall combined with warmth, which is exactly to the advantage of the fungus. Spores of the scab fungus spread quite actively with water, wind, animals and humans, and if they land on leaf blades, they begin to develop very rapidly, literally penetrating quite deeply into the leaf tissue. The vital activity of the fungus first leads to the appearance of spots on the leaf blades, and then simply through, round holes.
Peculiarities
Scab is fungal in nature. The first signs can be seen on young green leaves. These are light, cloudy spots that usually do not cause any suspicion among gardeners. Further on the spots you can observe the appearance of a velvety coating of greenish-brown color. The spots quickly increase in size, darken and unite. At this stage, the disease is already noticeable to the naked eye. Scab affects the pedicels and ovaries. Leaves that are completely captured by the fungus soon fall off.
Spots on leaves
Signs of the disease can also be seen on the fruits. They become covered with dark, round spots, and the flesh in these places becomes very hard. It may also crack and rot will penetrate deep into the fruit. Apples affected by scab grow in an uneven, ugly shape.
In winter, the fungus remains on the leaves. In spring you can see small black bumps on them. The so-called bags containing spores ripen in them. During flowering, these spores are released into the air. Rain is a great way to do this. Spores found on young leaves provoke further spread of the disease.
Signs of scab on fruits
A particular risk for a tree to become infected with scab occurs in the summer if the air temperature is in the range of 20 - 25 ⁰C and the air humidity is quite high.
Old apple trees are extremely vulnerable to fungus. The risk also increases if the trees are dense and there is little wind or sun penetration into some areas.
Over the summer, the fungus generates several portions of spores, so it only infects the emerging leaves and fruits.
Treatment of scab on apples
Currently, specialized stores offer dozens of different products designed to combat scab. The most popular means are:
Gamair (an analogue of Fitosporin) is available in tablets and is easy to use. In the fall, when processing apple trees, you need to dissolve ten Gamaira tablets in ten liters of water, and then spray the tree. It is recommended to perform 3 such treatments with a break of 10-15 days. Depending on the size of the crown, one tree will require from two to three liters of the prepared product.
Bordeaux mixture is a product that has been proven over the years, is effective and has an affordable price. When using this fungicide, remember that the agrochemical should be applied generously to the foliage and branches of the tree. After this treatment, the apple tree will receive a characteristic blue color. To prepare the solution, you will need to dilute 400 grams of lime and 400 grams of copper sulfate in ten liters of water. To treat one tree, 5-6 liters of solution will be enough. The first treatment is carried out after harvesting. Additionally, after 2-3 weeks it is recommended to perform another spraying.
Mole rat in the country: how to get rid of it?
Technology for growing cucumbers in a greenhouse
Chokeberry: planting and care
Rayok is an effective fungicide that maintains its effect for three weeks, quickly suppressing foci of the disease and destroying the fungal causative agent of scab. It is recommended to perform 4 treatments per season, two of which are carried out after harvesting in the fall. You need to dissolve 2 milliliters of rajka from the ampoule in a bucket of water. This solution will be enough to treat four apple trees.
Systemic agents
Systemic scab remedies enter the plant’s vascular system and act on the causative agent from the inside. Usually the active substance spreads from bottom to top, so treatment is carried out by watering.
Some systemic fungicides act locally: once they reach one organ of the plant, they cannot spread through the tissues of its other parts.
Such preparations are applied by spraying and often have a contact effect. That’s what they call: system-contact.
Systemic fungicides are used both for the prevention of scab and for its treatment. The effectiveness of drugs depends on the speed of distribution throughout all tissues. Their big advantage is their independence from weather conditions, but their disadvantage is that they are addictive. To prevent this from happening, alternate systemic drugs from different groups.
Azoles (triazoles)
This group is represented by a wide variety of fungicides. The most popular of them:
- Topaz. The active ingredient is penconazole. It has an inhibitory effect on pathogenic microbes without forming a protective film, therefore it is effective in all weather conditions. It has no analogues.
- Speed The active substance difenoconazole disrupts sporulation of pathogenic fungi. The drug forms a protective film, so it is not used before rain. Absorbs into fabrics within 2 hours. It is recommended to alternate Skor with Horus, a Swiss fungicide, a representative of the anilidopyrimidine group.
- Rayok, analogue of Skor. Destroys mushrooms at the genetic level. It gained popularity due to its high efficiency and lack of resistance.
A popular fungicide among summer residents is Topaz.
Other preparations from the azoles group for the garden are Split, Granite, Dividend, Impact. They have a long-lasting effect.
Strobirulins
This is a relatively new group of drugs with systemic contact action, which, according to experts, represent the future in the field of plant protection. Their advantage is their effect on a wide range of parasitic fungi.
This group of fungicides that destroy scab on horticultural crops includes: Strobi, Strobitek, Zato, Quadris. In terms of danger, they are close to biological substances.
A highly effective drug for scab - Strobi.
Treatment with strobirulins is carried out by spraying. The preparations are not afraid of moisture and rain, remain effective at temperatures of 1-4° C plus, and show high effectiveness in mixtures with other pesticides.
After 3-fold treatment, the effectiveness of strobirulins on the same plant in the next season drops by 1.5-2 times.
Benzimidazoles
Fundazol, Topsin M, Colfugo Super, Thiabendazole are low-toxic representatives of this group.
Fundazol is loved because it does not cause addiction for a long time.
Unlike strobirulins, they have a selective effect and are powerless against oomycetes, but have the advantage: addiction to the drug occurs after 3-4 years of use.
Horus
A Swiss drug from the anilidopyrimidine group has a protective and healing effect. The best time for application is early spring, when pathogens are in the germination stage and the air temperature has not warmed up to 15 °C. Harmless to bees and insects.
Feature of the drug: the working solution is used immediately after preparation.
Rubigan
This excellent preventative agent from the group of pyrimidinylcarbinols is used against scab in apple trees, pears, cherries, and grapes.
It has a local systemic effect and is applied by spraying. Capable of suppressing the disease if it has already been identified.
Aliette
The fungicide contains fosetyl aluminum and belongs to the group of phosphonates. Its value is the lack of resistance in pathogens. The second advantage is resistance to precipitation.
Alyette should not be mixed with preparations containing copper and nitrogen.
Treating apple trees for scab with iron sulfate
The active element of this vitriol is ferrous sulfate, up to 53%. It is a green-bluish crystalline powder.
The use of iron sulfate allows you to restore old trees and improve fruiting of apple trees. This is also a very inexpensive but effective remedy. Treating trees with it in early spring will free the tree from lichen and mosses.
The concentration of the solution should be 5-7%. If the solution is used in the fight against apple borer, then use a 3% solution.
Iron sulfate is an excellent insecticidal and fungicidal agent. For individual plants, in particular for apple trees, it is also an indispensable fertilizer. Microelements of iron are contained in the vitriol solution in a form that is easily accessible to the plant. Lack of iron causes a lack of oxidative enzymes in the plant and leads to the following diseases:
- leaf chlorosis;
- slow growth of new shoots;
- insufficient development of fruits.
Biological fungicides
Pesticides of this type “work” with bacteria or antagonistic fungi that destroy pathogens of fungal infections. Due to low toxicity, biological substances are harmless to plants, safe for humans, beneficial insects, and birds.
There are other valuable qualities of biofungicides:
- increasing plant immunity;
- stress relief after chemical treatment;
- increasing productivity;
- lack of addiction in pathogens;
- use regardless of the growing season;
- preserving the ecology of the site.
The disadvantages of biological products include a milder and weaker effect compared to chemicals and shorter protection, which requires repeated processing. The shelf life of the drugs is also limited - 1-2 years, while chemical pesticides retain their properties for up to 10 years.
Fitosporin
A systemic biofungicide, which is a natural antibiotic, contains spores of soil bacteria called “bacillus hay.” These are weather-resistant microorganisms. After processing, the fruits can be eaten the next day.
Phytosporin is used on all horticultural crops. They are sprayed, watered, and added to the soil when digging. Used in tank mixtures with other pesticides.
Analogues of the drug: Baktofit, Phytocid, Fitohelp , Vitaplan .
Agate
This fungicide is based on bacteria of the genus Pseudomonas aureofaciens (pseudomonas), a prominent representative of which is Pseudomonas aeruginosa. Shows high efficiency in tank mixtures with many products for protecting horticultural crops.
The correct balance of micro- and macroelements, pine extract and other bioactive components contribute to the active growth and development of the plant, develop resistance to drought, temperature changes, and increase the shelf life of collected fruits.
Hetomik
The drug is based on a mushroom antagonist of the genus Chaetomium (1 g of the substance contains 1-1.2 billion spores).
For better colonization when root treatment and adding fungicide to the soil, it is necessary to use organic matter as mulch.
Hetomik has a wide spectrum of action. Not compatible with chemical pesticides.
Trichodermin
Developed based on spores and mycelium of the Trichoderma mushroom. Used as a prophylactic and disinfectant.
Treatment is carried out by spraying the leaves of the plant, spilling the soil, and adding mulch.
Mikosan
Cells of the tinder fungus stimulate the development of a number of enzymes that stop the development of pathogenic microorganisms.
Mikosan combines well with various pesticides, fertilizers, and herbicides.
Other biological drugs: Alirin-B, Albit, Planriz.
Treating apple trees for scab with copper sulfate in the fall
The use of this fungicide has been practiced by gardeners for a long time, so its effectiveness has been proven many times. With its help, scab, nonillion, curly hair, phyllosticosis and other diseases are prevented and treated. However, copper sulfate has one significant drawback - it is highly acidic. This feature can be softened by the addition of some alkaline component. To spray apple trees, various solutions based on copper sulfate are prepared.
Subsequent spraying is carried out with a more gentle solution, for the preparation of which you will need 100 g of vitriol and 150 g of lime.
Burgundy blend. To prepare it, copper sulfate and soda ash are mixed in equal quantities. Then 100-150 g of this composition is dissolved in a bucket of water. Burgundy mixture is less effective than Bordeaux mixture, but its advantage is that it does not leave a film on the leaves.
Mixture with laundry soap. Sometimes, for spraying apple trees, a solution is prepared from 20 g of copper sulfate, 150 g of laundry soap and 10 liters of water. Such a remedy is least likely to burn the plant, but it does not always give the expected result.
How to treat the disease
If the spring was not very rainy, then pathogenic spores may not show their presence for a long time. When favorable conditions occur, they are activated. Often the disease can be noticed already in the summer, so treatment should be started immediately. Many amateur gardeners are wondering: how to treat an apple tree for scab in the summer?
To get rid of scab that affects trees in the summer, it is necessary to treat apple trees using biological preparations or folk remedies. How to get rid of a dangerous disease? Such treatment is effective in the early stages of the disease. Spores of the fungal disease will not be able to infect the apple tree at all, and will also not be able to accumulate in the apples that have set. Usually you can cure an apple tree from scab using Fitosporin. This special preparation can be used at any time during the growing season, even 2-3 days before harvesting. This product does not pose a danger to living beings. It is for the health of insects, animals and humans. The drug can be used at any temperature.
Many amateur gardeners treat apple trees against scab with Fitosporin, diluting it in the same container with a plant growth stimulating drug similar to Zircon. 5 g of Fitosporin is dissolved in 10 liters of water with the addition of 1 ml of Zircon. With the help of such a cocktail, you can not only fight a dangerous disease, but also help improve the immune system of apple trees. In addition, after treatment with such a mixture, apple trees become resistant to various diseases and begin to develop better. The restoration of microflora in apple trees occurs thanks to these drugs.
| Name of substance | When to process | How much preparation is needed for spraying | Number of treatments | How long does the drug last? |
| Use of "Skor" (difenoconazole) | Before buds open After flowering period | 2 milliliters of the drug are diluted in 10 liters of liquid | Process twice with a 15-day interval between them | The drug is effective for 3 weeks |
| Use of "Raeka" (difenoconazole) | Before buds open At the budding stage After flowering | 2 milliliters of the drug are diluted in 10 liters of liquid | Treatment four times with a 15-day interval between them | The drug is effective for 3 weeks |
| Application of "Strobe" (kesoxime-methyl) | When the kidneys are swollen; When in full bloom (June). | 2 milliliters of the drug are diluted in 10 liters of liquid | Process twice with a 25-day interval between them | The drug is effective for 6-7 weeks |
| Application of "Hrus" (ciprodenil) | At the beginning of bud break or during the appearance of corollas At the end of flowering (summer) | 2 milliliters of the drug are diluted in 10 liters of liquid | Process twice with a 10-12 day interval between them | The drug is effective for 4 weeks |
Treating apple trees against scab with urea
You can spray the apple tree with urea - this helps to destroy even those pests that are in the larval state. In addition, spraying with urea also benefits the plant itself - the substance saturates the tree with nitrogen, therefore it is used as a top dressing. In the fall, apple trees are sprayed when they have shed half their leaves.
Indoor cacti photos and names
Clematis: preparing for winter in the Urals
Calla lilies care, cultivation, storage
Autumn feeding of apple trees against scab
When choosing fertilizers, you need to focus not only on the seasonality of work. An important role is played by the age of the apple trees, their variety and, of course, the chemical composition of the soil. How to feed an apple tree in the fall? How to correctly calculate the dosage depending on the variety and age of trees? What weather should these events be held in? You will find answers to these and many other questions in this article.
In autumn, apple trees need to be fertilized with fertilizers based on phosphorus and potassium. Nitrogen fertilizers should be abandoned in the autumn so as not to provoke the formation and growth of young shoots. They will not survive the winter and are guaranteed to freeze. And their appearance and active growth will significantly weaken your apple trees before the onset of frost and they will most likely freeze out.
How to fertilize apple trees depending on soil composition
Before applying fertilizer to apple trees in the fall, you need to pay attention to the acidity level of the soil in your area. Increased acidity or alkalinity of the soil, even with careful and timely care, immediately affects fruiting. An outwardly healthy and abundantly flowering apple tree bears fruit very sparingly.
If the acidity level exceeds the norm, then the soil needs to be deacidified. To do this, add the following to the root zone and along the perimeter of the crown:
- Chalk;
- Slaked lime (fluff);
- Wood ash;
- Dolomite flour.
Of all the above fertilizers, gardeners deservedly consider wood ash to be an ideal fertilizer. It not only perfectly normalizes the acid balance, but also enriches the soil with potassium and phosphorus.
Any of the elements you have chosen must be scattered around the apple tree and carefully dig up the top layer of soil with a pitchfork. You shouldn’t go too deep when digging, so as not to damage the roots of the tree.
If alkaline values are high, the composition of the soil can be normalized using sawdust or peat.
Technology for growing cucumbers in a greenhouse
Blackberry shelter for the winter. Video
Sheltering grapes for the winter in the Moscow region video
Apparatus for treating apple trees against scab
Processing fruit trees in the fall is simplified thanks to existing devices of a mechanical or manual operating principle. These devices protect the gardener from contact with the preparations and spray them evenly. Regardless of the operating principle, all devices are equipped with a spray pump. The differences between mechanical devices and manual models are their ease of use. And, of course, there is a difference in their cost. Mechanical devices are more convenient, but more expensive. And to spray trees using a manual device, periodic pumping is required.
Application of mineral fertilizers
In spring, you can spray with a solution of mineral fertilizers. The treatment is carried out in the spring, for this purpose the following fertilizers are used:
- potassium sulfate;
- ammonium nitrate;
- potassium nitrate;
- potassium salt.
Chemical mixtures are used only for spraying infected apple trees.
The use of chemicals to spray infected trees. Gardeners often use spraying trees and tree trunks with a urea solution. Trees saturated with mineral microelements become resistant to fungal diseases.
