Tree Peony. Diseases

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

During the growing season, tree peonies can be affected by diseases. Correct agrotechnology and habitat conditions have a great influence on the resistance of varieties to pathogens. What pathogens appear on the bushes?

Types of diseases

The most common on tree-like peonies are:

• gray rot;

• rust;

• powdery mildew;

• ring mosaic;

• spotting;

• cancer of the root system.

Let us consider in more detail the signs of pathogens, measures to combat them.

Gray rot

The defeat is caused by the botrytis fungus. It actively develops at high air humidity in thickened plantings. Stems, buds, leaves, young shoots are attacked throughout the growing season.

At the base, a gray fluffy bloom appears, bearing spores of the fungus. The diseased place first darkens, then dries up, the stems break off, the buds die off. Causes rot of rhizomes, with a close location of ground aquifers, flooding with melt water, on heavy clay soils.

Excess nitrogen, the introduction of fresh manure contributes to the spread of the disease. Hibernates in soil, on plant debris.

Control measures:

1. Agrotechnical prevention (rare planting, balanced nutrition, soil loosening, burning of cut material, installation of drainage ditches).

2. Treatment of copper with preparations (copper sulfate, Bordeaux liquid, copper oxychloride), colloidal sulfur. The first time - in early spring, again - after 2 weeks.

3. When planting new bushes in the holes 2 handfuls of wood ash, 2 tablespoons of colloidal sulfur.

4. Herbal infusion of celandine is used on isolated plants. Steam 500 g of freshly cut grass with 5 liters of boiling water, leave for 2 hours. Spray twice at weekly intervals.

5. The diseased parts of the roots are cut to a healthy place. Withstand 10 minutes in a 1% solution of copper sulfate. Rinse with clean water. Sections are treated with brilliant green or a mixture of ash and sulfur.

Rust

The fungus pathogen Kronartium infects the leaves after flowering in July. On the surface side, blurry brown irregular spots are formed, in the lower part of the orange-colored cushion with spores.

Rapid spread of the disease within 3 days in wet weather can affect large areas of planting. Leaves curl, gradually dry out. The nutrition of the roots is impaired, which negatively affects the development, budding.

The intermediate plant in the fungus development cycle is pine, where the infection hibernates.

Control measures:

1. Avoid planting pine trees near peony plantations.

2. Destruction of plant residues throughout the season.

3. Treatment of bushes on leaves with Bordeaux mixture, colloidal sulfur, copper oxychloride, zineb. Reapply after 10 days.

Powdery mildew

A fungal disease that forms a white coating in the form of a cobweb on the leaves and stems. Tissues turn yellow, dry out when massively spread. Appears suddenly during flowering in high humidity. Hibernates on plant debris.

Control measures:

1. Treatment with a copper-containing preparation with the addition of green soap or soda ash solution (per bucket 50 g). The first time at the first signs of illness, the second - after 10 days.

2. Destruction of plant residues.

3. Spraying with infusion of rotted hay (1 kg of hay is poured with three liters of water, insisted for 3 days, filtered, the volume is brought to 10 liters).

Ring mosaic

The causative agent of the disease is a virus. Affects the whole plant. Irregular green pale or yellowish stripes in the form of rings appear between the veins of the leaves. On the bushes, there are healthy and diseased shoots at the same time.

Affected peonies lose their decorative effect, lag behind in growth, most of the buds remain closed. Carriers are sucking insects (leafhoppers, aphids). When cutting with one tool, the virus is transmitted from diseased plants to healthy ones.

Control measures:

1. Remove diseased shoots, followed by burning.

2. Use healthy planting material.

3. Destruction of leafhoppers, aphids.

4. Disinfection in a strong solution of potassium permanganate of the cutting tool.

We will consider the rest of the diseases in the next article.