Scab on a pear: how to fight and treatment
Scab on a pear is a dangerous fungal disease, it develops well in a humid, warm climate and can affect up to 100% of the crop. The causative agent of the disease is the highly specific fungus Venturia pirana, which develops only on the leaves, branches and fruits of the pear, without infecting other fruit trees.
The disease most often begins to actively develop on young leaves, manifesting itself in the form of dark spots with an olive bloom, which soon acquires a brown tint. The infection quickly spreads to the branches, flowers and leaves of the pear. On fruits, the fungus appears as dark chlorotic spots on the skin, while the pulp of the pear becomes corky. Even with small lesions, it is not worth storing such a crop, since the spots quickly grow over the entire surface. It is very important to timely recognize the signs of scab on the pear, to carry out treatment in order to prevent further development of the disease.
Scab on a pear can ruin not only the appearance, but also the taste of the fruit.
Reproduction of the fungus occurs in early spring, its spores quickly dissipate and ripen with the onset of a suitable temperature and humidity. Spores rise up with drops of rainwater and settle on the buds, affecting the blossoming leaves. The wind blows them to branches and fruits, thereby contributing to further damage to the rest of the tree.
The scab has a high resistance to severe frosts, and rainy weather contributes to the rapid defeat of the fruit tree. Several generations of fungal spores may develop during the summer season.
In autumn, scab forms new pseudothecia on fallen leaves and fruits, and during winter, the fungus germinates and disperses new spores. During the period of intense flowering of pears, they massively come out and are carried by the wind over long distances.
How to properly deal with a scab on a pear
If you do not take measures to combat scab in time, the trees gradually become covered with dark brown warts, merge and form necrotic areas with deep cracks, and the fruits become small, ugly in shape.
At the first symptoms of infection, it is necessary to treat with preparations with a fungicidal action based on copper
The scab is afraid of this microelement and dies, but for the best result, the treatment must be carried out several times per season:
- when budding;
- after flowering;
- two weeks before harvest.
In autumn, the affected branches and fallen leaves must be burned in order to prevent the fungus from re-developing the next year, since it has a high vital activity.
Preventive measures are necessary even if the trees are healthy and yielding well. Pears from a neighboring area can become a source of scab infestation, because spores in the spring can fly away with wind currents. You can protect your garden from fungal infection if you follow the simple rules for caring for fruit trees.