Content
Some fruit trees suffer from scab. Diseased pears and apple trees become weak, and this, in turn, negatively affects the yield and quality of the fruit. The disease affects all parts of plants. A description of pear scab, methods of prevention and treatment will be presented below.
What is scab
The causative agent of the disease is a marsupial fungus that overwinters in fallen leaves. In spring, the spores begin to ripen in the fruiting body. This process can last, depending on the weather, for 2 months. Then, when the rains begin, the fruiting bodies are freed from spores, scattering them over all parts of the fruit tree. In warm and humid weather, the scab pathogen germinates quickly.
You can notice scab on a pear by the following signs:
- flaky skin;
- presence of stains;
- cankers and warts on the trunk, leaves, flowers and fruits.
Causes and provoking factors
Scab on a pear does not appear just like that, there are reasons for this:
- The soil is too wet. In spring - after the snow melts, in summer - due to fogs of dew and rain.
- Thickening of plantings, due to which scab spores move to a new place.
- Planting varieties with weak immunity.
- Close proximity of crops affected by the same disease.
Development and symptoms of scab
The scab strikes first on the young shoots of the pear:
- the bark becomes covered with swellings;
- changes color to olive;
- peeling appears.
When the scab is firmly established on the shoots of the pear, it intensifies its harmful activity on the foliage. The lower part of the plate is covered with olive spots with a velvet-like coating. These are the plantations on which scab spores develop.
The development of spores leads to the death of foliage, the fruit tree weakens, as the water balance is disturbed. The pear will bear fruit poorly for 2 years.
In rainy weather, scab quickly spreads to flowers and ovaries: the signal is dark specks with spores of the marsupial fungus. The ovaries are not able to fill, they fall off.
If the development of the disease occurred after fruit set, then the scab spreads to them and affects them. Pears are covered with gray-black spots. With severe infection, the affected areas may merge together. Fruits affected by scab do not grow, become ugly and eventually fall off.
How to deal with scab on a pear
Experienced gardeners inspect fruit trees throughout the growing season. At the slightest sign of scab, they begin to fight it. But a disease is usually easier to prevent than to fight it. So prevention should come first.
How to get rid of scab on a pear in the fall
Since the spores of the marsupial fungus survive the winter well, treatment of scab on pears should begin in the fall:
- First, you need to rake fallen leaves under the trees. If there were problems in the summer, then it is better to burn the collected leaves rather than put them in a compost pit. Otherwise, you can provoke the proliferation of scab spores in the spring.
- After this, they dig up the trunk circles and row spacing in the garden.
- On a sunny day, after all the foliage has fallen off, you need to spray all parts of the fruit tree with a urea solution. Dissolve 50 g of mineral fertilizer in a liter container of water.
Fighting scab on pears in summer
During the summer, thin out the crown of the pear tree if the crown is thickened.
Bordeaux mixture is used to treat scab. Since the effect of the drug is short-term, only 2 weeks, treatments must be carried out up to 7 times during the growing season.
The first time preventive maintenance of fruit trees is planned before the flower buds bloom. A bucket of water requires 300 g of copper sulfate and 350 g of lime.
The next spraying is carried out after 14 days. The solution of Bordeaux mixture is made a little weaker than the first time: for 10 liters of water take 100 slaked lime and copper sulfate.
It is not necessary to prepare Bordeaux mixture; vitriol alone will do. In this case, pears are sprayed against scab after flowering: 5 g of the substance per bucket of water.
- 90% copper oxychloride;
- 80% "Polycarbocin";
- "Polychomus";
- colloidal sulfur.
Fruit trees are sprayed with any of these preparations 3 times:
- when the buds come apart;
- at the moment of tying the ovaries;
- in 14 days.
To prevent and treat pear scab in the summer, you can use drugs that act systemically:
- "Skor." Treatment with this drug is carried out 2 times every 20 days. The first time, while the buds had not yet bloomed. Add 2 ml of product to 10 liters of water.
- "Strobe." The treatment kills not only the spores of the marsupial fungus, but also powdery mildew. Pears must be sprayed with Strobi 3 times with an interval of 14 days. The drug is valid for 35 days. This is one of the products that can be combined with fungicides.
To treat pear scab, mineral fertilizers are often used. They are not only sprayed with them, but also fed to fruit trees at the root. You can take any mineral fertilizer from the list:
- 10% solution of ammonium nitrate or ammonium;
- 3-10% solution of potassium chloride or potassium sulfate;
- potassium nitrate or potassium salt.
Preparations for scab on pear
Now we need to find out what other means can be used to combat the marsupial fungus on a pear. Experienced gardeners first use folk remedies; if they do not solve the problem, they move on to more radical measures - chemicals.
Folk remedies
In recent years, gardeners have been abandoning chemicals in their summer cottages in order to obtain healthy, environmentally friendly products. After all, many components of chemical preparations are eaten into the finished product, even if all treatments are carried out strictly according to the instructions.
What folk remedies can be used to treat pears for scab:
- Dry mustard. For a 10 liter bucket of warm water you need 80 g of powder. Dilute mustard in a small amount of water, grind well to remove lumps. Then pour the mixture into a 10 liter bucket.Pears are sprayed with this composition 3 times: during budding, after fruit set, when the flowers fall, and at the time of filling the pears.
- Horsetail. Cut the green grass, put it in a bucket (1/3) and fill it with water. After steeping for 3 days, you can spray the pears against scab. The work is planned for early spring, when the leaves are just beginning to bloom.
- Salt. A solution of this substance is used to treat fruit trees in early spring, while the buds have not yet blossomed. A 10 liter bucket will require 1 kg of salt.
- Potassium permanganate. For 10 liters of water, 5 g of the drug is required. Pears are treated with it several times during the summer. The first spraying is when the foliage opens. The second time is when the flowers fall and the ovaries begin to form. The third treatment is left at the time of fruit ripening.
Chemicals
There are a number of means that you can use to get rid of scab - drugs with a wide range of actions:
- “Poliram DF” is a non-toxic granule for plants and insects.
- Tridex is a complex granular product that allows you to get rid of scab on pears and other fruit trees. The fungicide does not pose a danger to insects. The content of manganese and zinc makes it possible not only to treat pears from scab, but also to feed fruit trees at the same time.
- “Merpan” is not addictive to the fungus. In addition, the drug can be used with other systemic agents.
- "Chorus" is a broad-spectrum active agent. Spraying can be carried out in any weather, even in rain, if the temperature is not lower than +10 degrees.This product is safe, so the bees can safely continue their work of pollinating pears.
Treatments with these fungicides are alternated and carried out several times during the growing season. Dissolve the products in accordance with the instructions.
Preventive measures to combat pear scab
To prevent pears from being affected by marsupial fungus, it is not necessary to use chemicals. You need to follow some recommendations:
- Choose the right site for planting pear trees. Pear likes a place that is sunny and well blown by the wind. If several seedlings are planted, then a distance of at least 2.5 m is left between them.
- Carry out sanitary and formative pruning of pear trees in a timely manner to avoid scab disease.
- Proper collection of fruits will help save them from infection. Slightly unripe pears are removed from the trees. Those fruits that lie under the trees are not recommended to be collected and sent for storage. They are suitable for processing: cooking jam, compote, dried fruits.
- In the fall, you need to do a general cleaning of the garden. Collect all leaves and burn. In this case, the fungi will not have a place to overwinter.
- If scab has affected 1 pear or apple tree on a plot, it is necessary to carry out preventive treatment of all fruit trees and shrubs that have low immunity to this disease.
Varieties resistant to disease
Breeders involved in breeding new varieties of pears try to obtain plants with good immunity to many fungal diseases, including scab.
Therefore, before purchasing seedlings, you should give preference to varieties that are resistant to scab, for example:
- Bere Gardi;
- Etude;
- Trembita;
- Bere Ardanpont;
- Vyzhnitsa;
- Bere Bosk.
Conclusion
Knowing the description of pear scab, gardeners can easily cope with the problem. You just need to remember about preventive measures. If a disease occurs on fruit trees, the fight must be started without delay, otherwise you may be left without a pear harvest.
