Scab on an apple tree: photo, description, how to treat

Many gardeners have come across such an unpleasant phenomenon as scab on an apple tree on their site. Questions about how to get rid of scab on an apple tree, how to prevent its appearance and protect apple trees from being damaged by a parasitic fungus do not lose their relevance. Unfortunately, getting rid of it is not easy, but it is quite possible if you follow the recommendations given in this article.

Scab on an apple tree photo description

What does scab look like on an apple tree

Scab is a fungus scientifically called Venturia inaequalis. It develops in high humidity, when damp and rainy summers are issued, rich in foggy days. The scab on an apple tree begins with the defeat of the bark and young shoots in early spring, gradually moving along the tree.

Without proper treatment, young plants can die, and mature trees lose health and yield. It is better to know the signs of scab on an apple tree in advance. The scab on the leaves of the apple tree manifests itself quite clearly - in the form of swamp-colored spots covering the ovaries, leaves and the apples themselves.

Over time, these spots darken and crack. Young leaves located at the ends of the shoots are most vulnerable to scab. It is they who fall ill first, become covered with all darkening spots, gradually merging into one whole. Then the leaves dry up and begin to fall off. Fruits also become completely covered with dark spots over time and crack.

All varieties and varieties of apple trees, regardless of the region of their growth, are exposed to the influence of scab. The fungus develops most successfully in conditions of thickening of gardens and high humidity, first of all affecting the youngest and oldest trees.

The only way to prevent massive scab damage to apple trees is to take regular preventive measures and remove the affected parts of the tree in the initial period of the disease.

Also, despite the versatility of the disease, there are a number of varieties that have a certain degree of scab resistance. They will be discussed below.

Unfortunately, the fungus is notable for its vitality and can overwinter in the fallen leaves remaining on the site. That is why in the fall it is necessary to collect the leaves in heaps and take them outside the garden.

In the spring, characteristic dark seals will appear on the remaining foliage, in which fungal spores mature, which will inevitably enter the external environment, and this process is especially intense in wet weather.

Mature spores are thrown out throughout the summer and infect the surrounding trees without affecting photosynthesis - the apple tree continues to grow, but the fungus also grows, capturing all its parts. This inevitably affects the appearance of the tree and health, the quality of its fruits. Have a high probability of getting scab apple varieties Melba.

Scab on an apple tree: how to treat it and what methods of prevention exist

Scab on an apple tree: how to fight

Removing the parts of the tree affected by the fungus is a rather radical, but effective way of dealing with scab. At the end of the season, it is necessary not only to cut off diseased branches, collect foliage and fruits with traces of the fungus, but also process the bark of the tree, leaving only healthy layers of tissue.

As mentioned above, in the fall, the fallen leaves must be cleaned, then it can be burned or buried in the ground away from the apple orchard.The ground around the apple trees needs to be dug up, the lower part of the trunks should be covered with a layer of whitewash, and the crown should be sprayed with copper sulfate (5% solution).

In the case when apple trees are located on a grassy lawn, its coating also needs to be treated with ammonium nitrate (10% solution). Spring prophylaxis involves the use of the Zircon immunostimulant, with which the trees should be sprayed before the buds begin to bloom. They can also process apple trees in the fall.

In addition to irrigation with "Zircon", it is necessary to prune dried branches and exfoliated bark, as well as whitewash the apple tree trunk. To do this, use a ready-made solution purchased in a store, or a home-made mixture of 5 kg of lime and 1 liter of copper sulfate, diluted with 10 liters of water.

Garden var will help cover up the wounds on the branches left after pruning.

Many are interested in the question of how to sprinkle plants from a scab on an apple tree? At the end of the flowering period, it is recommended to spray the apple trees with the fungicides "Cineb" and "Kuprozan", or the indelible "Horus". Other preparations suitable for processing are Vectra, HOM, Hometsin.

What other effective drugs are there for scab on an apple tree? Also very popular is the so-called "blue irrigation" with the use of Bordeaux liquid, which gives the leaves a bluish tint. The systemic fungicide "Skor" is considered effective: 1 ampoule of this drug is enough for 10 liters of water.

Re-spraying with preparations is recommended after 3-4 weeks, and not only the crown, but also the trunk itself, the surrounding soil and neighboring plants should be treated.

Scab control on apple trees in spring. With the arrival of stable heat, you can spray the apple trees with solutions that slow down the development of the fungus - "Fludioxonil", "Abiga-Peak", "Gamair". In this case, it is necessary to follow the recommendations for dosage and method of application indicated on the package.

The last time preventive irrigation of apple trees is carried out no later than half a month before harvesting.

Scab on an apple tree: how to fight in the summer? Reliable protection against scab is given by the use of such drugs as "Fitoflavin" and "Strobi" in the summer. The first one must be diluted with water in a proportion of 20 ml per 10 liters and treated trees with it 3-4 times during the season with an interval of 15 to 17 days. In the second case, 1-3 treatments will be required with an interval of 2 weeks.

Of all the fungicides, the least toxic is Zircon, which is based on an extract of Echinacea purpurea and therefore does not harm people, animals and the environment. In this regard, its use is effective only if the disease has not yet fully developed.

With a serious degree of scab damage, a more effective remedy from the above list will be required. Due to their toxicity, you should take care of protective equipment in advance - a mask and gloves. It is also recommended to irrigate apple trees with fungicides on a windless day after rain, preferably in the evening or morning.

Is phytosporin used for apple scab? It is possible to increase the immunity of apple trees with the help of environmentally friendly preparations "Phtosporin M", "Baikal EM-1". They contribute to the prevention of a fairly wide range of diseases of bacterial and fungal origin. They are recommended to be processed in June.

So, the first irrigation with fungicides is carried out on the eve of foliage blooming, the second - before the opening of the buds, the third - at the end of the flowering period. In the summer period, preventive treatments for fungus are carried out every 2-3 weeks - according to the situation. If the summer is rainy, the amount of irrigation can be increased to 5-6.

Preparations for scab on an apple tree - the use of dressings and various types of fungicides

It is important to understand the mechanism of action of fungicides and carefully study their composition.Preparations produced under different names are often based on the same active substance, the frequent use of which will lead to the development of immunity in the fungus to it.

Experienced gardeners recommend using preparations with various active ingredients for the preventive treatment of apple trees.

Another important point is the hazard class of the fungicide, which is always indicated on the package. For summer cottages and horticultural farms, it is different, therefore, means with 3-4 class of danger are suitable for processing home gardens.

When treating scab on an apple tree, one should take into account its presence in a neighboring area, which can negate all efforts to protect your garden - in this case, the treatment will only last for one season, and the risk of disease increases significantly. That is why it is necessary to exchange information about plant diseases with neighbors in order to jointly take measures to combat them.

For preventive treatment of apple trees, fertilizers used for foliar applications are suitable. But for the medicinal effect, you need to increase their concentration, and for preventive irrigation, a lower percentage of dissolved fertilizer is suitable.

Thus, potassium salt and saltpeter (15%), ammonium nitrate (10%), ammonium sulfate (10%), in the autumn period - nitroammofoska (10%) and urea (7%) help and use scab on apple trees. Fertilizers have a double effect - they nourish trees and destroy fungi and other pests.

List of fungus resistant varieties

Breeders have bred about 150 varieties of apple trees that are resistant to scab. Below are just a few:

1. Uslada apples have a sweet and sour taste and a pink hue of flesh under a red peel with dark raspberry stripes. The variety is characterized by frost resistance and high yield. Due to the rapid growth of branches, apple trees of the "Uslada" variety need to be shaped into the crown.

2. Variety "Medunitsa" stands out for the honey taste of the fruit and the long shelf life (about 2 months). Fruiting begins from the 4th year of the tree's life and occurs at the end of summer. Like the previous variety, it needs crown formation.

3. The variety “Star».

4. Varietal variety "Chudnoe" refers to self-supporting undersized trees and yields yellow apples weighing up to 0.2 kg.

5. "Moscow winter" is a tall variety with a dense crown. In addition to resistance to cold weather, it is distinguished by a rather late fruiting period (September) and a long shelf life of apples.

6. The unpretentious variety "Orlinka" gives a bountiful and early harvest (mid-August), which, however, is not stored for long.

7. Other varieties resistant to scab - "Nocturne", "Juno", "Perlina Kiev", "Orpheus", "Fortuna", "Saffron Peppin", "Soyuz", "Yekaterinodarskoe", "Red amber"," Golden Summer "," Talida "," Kariot 7 "," Honey Gold "," Scythian Gold "," Dawn "," Fairy "," Spring ","Lyubava"," Vasilisa "," Margo ".

Scab on an apple tree: photo

Scab on the leaves of an apple tree photo

What does a scab look like on an apple tree photo

scab on an apple tree under a microscope

Conclusion

The fight against scab on an apple tree begins at the stage of planting apple seedlings in the ground and requires compliance with certain rules, an acceptable distance between trees. The crown of adult apple trees must be thinned, the branches must be cut off, and the tree itself must be fed with fertilizers that increase its immunity.

A systematic examination of apple trees will allow you to quickly notice the first signs of scab damage to trees and stop the disease at an early stage. Methods for dealing with a disease such as scab on an apple tree have been listed in this article.