Cherry And Sweet Cherry Scab

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

Cherry and sweet cherry scab spreads mainly during the flowering period - especially often mushroom spores are thrown out after heavy rainfall. It develops most often on fruits and on the undersides of cherry and cherry leaves, and the first symptoms of a harmful misfortune can be detected as early as May. In damp years, the area affected by this disgusting disease is especially large. To reduce the scab attack on fruit trees, they need to be properly cared for - healthy and strong trees are always much more resilient

A few words about the disease

On the leaves, as well as on the fruits of cherries attacked by scab, one can observe the formation of olive-brownish velvety specks, abundantly covered with mushroom spores. The diameter of such spots is usually in the range of 0.1 to 0.3 mm. At the same time, the edges of the leaves almost always turn brown and dry out. Often, the leaves roll up into tubes, and after some time they completely dry up and slowly begin to crumble.

The green berries of cherries and cherries shrivel and are characterized by poor development, and tiny cracks often appear on already ripe fruits. The specks on the fruits are always depressed, and the taste of the scab-affected berries is usually bland. Almost all berries, as a result of being hit by an ill-fated disease, become one-sided, ugly and woody, which has a detrimental effect on their commercial qualities.

The pathogenic fungus Fusicladium cerasi, which overwinters on fallen leaves, causes cherry and sweet cherry scab. And the main place of preservation of the pathogen is dried fruits. Spraying, fungal spores, when they hit the green parts of vegetation, contribute to the formation of new specks.

Fungal conidia are usually spindle-shaped, arranged in chains and have an olive-brown color. They can be either cylindrical or elliptical, and their tips are usually slightly blunt and narrowed.

Scab has an extremely negative effect on the photosynthesis of fruit trees and almost always leads to a noticeable decrease in the yield of bright juicy berries. Infected leaves fall off prematurely, as a result of which the fruit trees become weakened and poorly prepared for winter.

How to fight

For preventive purposes, all fallen leaves and fruits under garden trees should be collected and burned in a timely manner, and the soil in the near-trunk circles should be dug up as carefully as possible. Moreover, such a digging should be carried out not only in early spring, but also with the onset of late autumn.

In scab-infected orchards, it is recommended to spray the soil and fruit trees with Nitrafen. Such spraying is called eradication, and it is carried out in early spring, before tiny buds bloom. It is allowed to carry out treatments with one percent Bordeaux liquid - it is usually used when the buds have already begun to bloom. Twenty days after flowering, a second treatment will be appropriate. As for the third spraying, then it's time for it - the period after harvest. Well, if the infestation of the gardens is especially high, a couple of weeks after the third spraying, you can carry out the fourth one.

A good effect is given by spraying fruit trees with copper oxychloride, 40 g of which is diluted in ten liters of water. It is important to take into account that Bordeaux liquid and other preparations containing copper can cause leaf burns, therefore, when using these funds, care must be taken.

When the first symptoms of scab are found, it is recommended to treat the vegetation with Kuprozan. You can also use "Phtalan" (ten liters - from 30 to 50 g) or "Captan" (dosage is the same as the previous one). Treatment with ammophos or 1% superphosphate can also stop the development of a harmful fungus.