Diseases Affecting Pear Trees

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

The sweet fruits of the pear have a pleasant aroma, are saturated with vitamins useful for the body. A healthy adult tree is capable of producing up to 100 kg of a tasty product. Diseases trapping plants during the growing season can significantly reduce these indicators. How can you help your beloved pets cope with harmful factors?

Types of pathogens

Several types of diseases can appear on the pear during the season:

• scab;

• rust;

• serebryanka;

• burn;

• crayfish;

• cytosporosis;

• spotting;

• rot;

• tinder fungus;

• mosses, lichens.

In order to correctly apply protective measures, it is necessary to know the signs of the manifestation of diseases. Let's consider the main "culprits" in more detail.

Scab

The disease is most widespread in rainy years in the first half of the season. Harmfulness is expressed in a decrease in yield, a deterioration in its quality. The fruits become ugly, with many round, grayish-black spots. In places of damage, the skin cracks.

The causative agent of the disease is a highly specialized marsupial mushroom that damages only the pear. It strongly affects all parts of the plant. It hibernates on fallen leaves in the form of spores, mycelium remains on diseased shoots. In spring, in humid, warm weather, primary infection occurs, followed by spore germination.

Initially, oily yellow spots with an olive bloom appear on the leaves on the underside of the leaf blade. Small swellings form on the bark. Bursting, they turn into cracks, peeling. The affected parts of the plant fall off prematurely. Under favorable conditions, the mushroom gives 8 generations over the summer.

Control measures:

1. Burning fallen leaves in autumn.

2. Planting in wide rows of young seedlings for better ventilation.

3. Digging the soil around the trees, in the aisles.

4. Thinning the crown, cutting off excess branches.

5. Spraying twice a season (during the period of leaf blooming, intensive growth of new branches) with preparations of Bordeaux mixture, polychoma, copper oxychloride.

6. Application of wild garlic infusions.

Rust

The causative agent of the disease is a highly specialized fungus that affects mainly branches, less often fruits, leaves. Juniper is an intermediate plant for the development of the fungus. A perennial mycelium forms on it. Spores are scattered by the wind onto the pear in spring, where they cause infection. It hibernates as a mycelium on an intermediate crop.

If the pear is severely affected by rust, the leaves fall off prematurely, and the fruit yield decreases. After flowering, reddish or orange spots form on the upper side of the leaf plate. With increased air humidity, the disease develops more strongly than in dry weather.

Control measures:

1. Avoid planting junipers next to pears.

2. Use of milkweed infusions or solutions of Bordeaux mixture, zineba, colloidal sulfur before and after flowering, 2 weeks after the last spraying.

Silver (milky shine)

It manifests itself on the leaves in a color change. They become "milky" in color. Later, patches of dead tissue appear between large veins or along the edges. The leaf plate becomes dry, brittle.

The cause of the disease is freezing of wood, accompanied by the introduction of fungal spores. The affected branches dry up. By autumn, fruiting bodies appear on the bark, having leathery, thin plates 2-3 cm in size.

On the underside of the leaf plate, the spores scatter, forming new infestations. The wood gets inside through mechanical damage. Germinate in September-October or early spring in April-May during wet weather.

Control measures:

1. Increasing winter hardiness:

• loosening the soil;

• application of a balanced complex of complex fertilizers;

• in the fall, water-charging irrigation;

• regular treatment of wounds, cracks by covering the sections with RanNet or garden varnish;

• protection of trees from sun-frost burns (whitewashing with slaked lime).

2. Removal, burning of dried branches.

3. Foliar, root top dressing with urea in combination with spraying with onion infusion.

Pear burn

The causative agent of the disease is bacteria. Refers to a quarantine disease. Flowers, fruits, young shoots, leaves are affected.

Young shoots, flowers, when blooming, unexpectedly wither, leaves curl up. The fruits do not have time to ripen, shrivel. All affected parts of the pear turn black, remaining hanging until autumn.

The disease is similar in features to black cancer. But unlike her, the affected branches become watery. The escaping dark yellow liquid, turning into a brown color, solidifies on the shoots. The bark becomes covered with bubbles, cracks.

The disease spreads from top to bottom of the cortex without affecting the vessels. Rain transfers the pathogen from a diseased tree to a healthy one with spray. Insects (bark beetles, aphids, bees) are additional vectors. Once on the pear, bacteria penetrate into cracks, wounds, causing new infections.

Control measures:

1. Compliance with quarantine - the acquisition of healthy planting material.

2. Growing of relatively resistant varieties of pears.

We will get acquainted with cancerous lesions in the next article.