Alternaria potato: description, control measures, prevention

Late blight Potato alternaria is a very dangerous disease, both for plants and for humans. The fruits of the plant infected with this fungus should not be eaten, as serious diseases such as bronchial asthma and allergies can frolic. Today we will tell you everything we know about this disease.

Potato Alternaria disease: causative agent and causes of the disease

Alternaria photo

Alternaria the causative agent of the disease is Alternaria mold, most often solani, alternate, infectious diseases. But they can also infect other species of this fungus. The mycelium of the fungus is represented by thin, colorless fibers woven together, separated by septa.

The plant becomes ill when spore mycelium hits a newly planted tuber. After being hit, he waits for favorable weather conditions to begin his active development.

The most vulnerable are weakened plants, which have lowered immunity, and they cannot resist the disease.

Immunity decreases due to bad

· Weather conditions: heat, drought, cold snap.

· Wrong watering regime, i.e. the soil is either too waterlogged, or it has not been watered for a long time and is very dry.

Poor soil

Deficiency or excess of trace elements (potassium, phosphorus, nitrogen)

Infected planting material

Alternaria (dry spot) of potatoes: description

potato alternaria photos

The disease affects the stems, leaves, tubers of potatoes. Symptoms appear 15-20 days before flowering. Large brown-brown spots appear on the leaves, which gradually merge together. As a result, the leaves curl, turn yellow, dry up and fall off. On the stems, spots also appear, but they have an elongated shape. The tubers break the irregularly shaped depressed spots, their color is darker than the peel of a potato. The spots gradually merge, covered with a network of wrinkles in the form of a circle. The tissue of the tuber pulp is necrotic. After a while, nycrosis turns into a very dense, dry, dark brown rot.

The plant can become sick two to three days after infection if the environmental conditions are favorable for the growth of the fungus, namely high humidity and temperatures of 25 degrees or higher.

Alternaria affects not only potatoes. A huge number of fruit, vegetable and berry crops suffer from this disease. They parasitize tomatoes, cabbage, pumpkin, carrots, grapes and other plants. Alternaria causes great harm to the crop, reducing it by 25-30%.

Disease Resistant Varieties

Unfortunately, the varieties that never get sick with this disease have not yet been bred. But there are varieties that are more or less resistant to it.

1. Adrietta. Yellow-fleshed potatoes that are good enough to resist disease.

2. Bronnitsky. In addition, Alternaria is resistant to scab and black leg.

3. Lyubava. It is an early variety that has white tubers. Does not lose whiteness even during cooking. It resists alternariosis well, but is affected by scab.

Alternaria: treatment

Unfortunately, heavily affected plants cannot be saved and must be removed and burned. But if only the first signs of this disease appear on the plant, you need to immediately take measures to combat it.

The fight includes the treatment of plants with biological and chemical substances.Both should not be used often, a maximum of four times per season.

Alternaria: biological control measures

This method is most often used to treat tubers before planting. The most common drugs are: "Agat-25", "Integral" and "Bactofid".

For processing of already released plants use "Planriz".

Potato Alternaria: Chemicals

Used to treat an adult plant. It is toxic to humans. Therefore, the treatment is carried out in calm weather and only in protective clothing (suit, goggles, gloves, respirator or mask).

Suitable for processing are 0.3% solution of such drugs as: "Utan", "Thanos", "Profit", "Novozri", "Penkoceb", "Mancoceb", "Kuproksat". 0.5% solutions of "Cupricola", "Metaxil", "Metamil" and others.

In the early growing stages of plant development, you can use the drug "Bravo" in a dosage of 3 liters per 1 hectare. The "Maxim" preparation can be used to treat seeds before storing them.

Disease prevention

1. Cleaning the garden, where the potatoes will be planted, from all plant residues. You can remove them manually, but if the garden is large, then you can plow deeply with a tractor.

2. Observe the rules of crop rotation. Do not plant the same families next to each other, change the planting site every three to four years. Plant potatoes after good predecessors.

3. Make top dressing in a timely manner. The soil must contain enough nutrients to grow potatoes. But don't overdo it with fertilizers, especially nitrogen and potassium.

4. Try to plant potatoes resistant to this disease.

5. Harvest the entire crop. Do not leave tubers in the soil, even whole or cut. Since they will serve as a breeding ground for the fungus.

6. During harvest, do not damage the potatoes. Dry it well and treat it with a fungicide before storing it.

I hope this article has helped you in the fight against this disease. Use the information above to grow a healthy crop.