Potatoes grow well in almost any climate. It tolerates acidic soil, but the yield is significantly increased after liming. A large amount of moisture and light are, in fact, the only conditions for the growth of potatoes. But even under ideal conditions, the culture is at risk of infection by fungi, viruses and bacteria. Here we will consider the most basic problems and universal solutions that will help to cope not only with the presented examples, but also to prevent many other similar diseases. Despite the fact that varieties of potatoes that are resistant to late blight, nematode or scab are hatched , diseases and pests continue to destroy the crop. But for every enemy there is a weapon.
Potato Diseases and Control
A large number of various enemies of potatoes significantly reduces the level of the crop. These include not only fungi and insects, but also viruses that infect tubers and inflorescences and interfere with normal growth. Therefore, it is very important to carry out many preventive measures before sowing and during cultivation in order to preserve your potatoes. Diseases and pests cause great damage, so it is better to invest and save yourself from worries than to lose half the crop.
The use of poisons and chemicals reduces the nutritional quality of potatoes; it can become harmful and dangerous not only for beneficial insects, animals and birds, but also for people. Potato diseases and their control require special attention before planting. Let us consider in detail all their types in this material. For a more complete assimilation of information in the article there is a photo of diseases of potatoes, as well as pests that parasitize on tubers.
Wireworm
The wireworm is the larva of the nutcracker. It is a small gray insect 12-15 mm long. It got its name because it makes a clicking sound, turning from its back to its paws. One female lays from 50 to 200 eggs in the spring, from which the unfortunate wireworm is born. Larvae are capable of destroying a whole crop, therefore, first of all, it must be protected from the beetles themselves.
Wirewalking
There are three methods that are suitable for combating this parasite:
- The peeled potato is strung on a stick and buried in the ground by about 7 centimeters. It is better to make several of these potatoes to cover a large area. The larvae of the nutcracker beetle will gather on it, and after four days it will already be possible to dig it out. It will be possible to destroy pests with the help of boiling water or fire.
- When planting potatoes, pour sunflower oil with finely chopped eggshell into the ground. Such a solution will kill the wireworm before it reaches the potato. This method will help the crop not only from the wireworm, many other earthen insects die in such a solution, for example, a bear.
- Two weeks before planting, bury corn grains in the ground - about 2-3 nests per square meter. Not only potatoes are attracted to wireworms, larvae will also be happy to gather around grains. When the corn sprouts, it can be dug up, robbed of larvae and burned or poured with boiling water.
Late blight
Late blight (late blight) is not only the reason for the loss of tomato harvest, but also the most common diseases of potato, and the fight against them is important for all farmers, regardless of the crop grown. For potato late blight is especially fatal, since within two weeks it can infect the entire field. Losses reach 70% of the crop. Blight spreads through fungal spores, which allows it to quickly move underground and infect tubers.
In the first days of the onset, late blight is manifested in darkening on the leaves. A white coating also appears on the underside of the sheet. These are sprouting fungus spores. They fall down, infecting the roots and fruits of potatoes. Brown spots appear on the tubers a little later.
Blight control
Dangerous mushroom requires serious comprehensive measures. So, you must:
- Use potato varieties resistant to late blight.
- Select healthy tubers for planting.
- Treat tubers with fungicidal agents.
- Spud when necessary.
- Increase the dose of phosphorus-potassium fertilizer.
- Apply fertilizers containing copper, or spraying with a solution of copper sulfate.
- Remove the tops before harvesting.
Nematode
The nematode disease is not caused by a virus or a bacterium, but by a microscopic worm parasitizing on potatoes. Checking the presence of the pest is easy: if the bushes fade, and their small leaves have an uneven or even pale color, there is a nematode. The bushes become frail, and the roots are small. In July, small balls (with half a millimeter) with small processes will appear on these roots. These are female nematodes, if they continue to develop, they will turn into cysts, which remain in the ground for another 15 years. There are about 600 worm eggs in the cyst.
Nematode Fight
After the appearance of the nematode, it is necessary to wait at least 6 years before planting the plot again. However, there are other ways.
Potatoes of an early or nematode-unstable variety are stacked in boxes in a single layer, sprinkled with peat chips and planted after 20 days. After 50 days, the crop is harvested, and the site is thoroughly cleaned of tops. The plot itself is sown with legumes or corn. This will clear the soil of the worm by about 70%.
If you plant rye on the plot, this will also significantly reduce the parasite population.
It is worth noting that potato attracts a nematode more than other plants.
Scab
The most common potato disease after late blight is scab. It impairs the quality and presentation of the tubers and reduces the level of starch in them by almost 30%. Productivity is almost halved. During storage, infected tubers are very susceptible to rot.
The causative agent of scab is mold - a radiant mushroom. It penetrates into potatoes through lentils and mechanical damage, forming sores on the surface that merge together and form cork tissue. A white coating appears on the tubers - mycelium of the radiant mushroom. When dried, they disappear, and the flesh remains almost unchanged.
There are five types of lesions:
- Flat . It affects the skin of young tubers, from which the peel hardens.
- Mesh . Covers tubers with many mesh grooves.
- Convex . Appears in the form of grooves, which are later covered with growths.
- Deep Deep ulcers of various shapes, surrounded by ruptures of the peel. Visible when harvesting potatoes.
- Convex deep. The combination of two types of damage. Growths with deep ulcers and ruptures of the peel.
The scab pathogens persist in the earth for several years. They are not influenced by negative climatic factors, persist even in drought and at a temperature of -30 ° C. Hot and dry weather during flowering only contributes to infection.
The source of infection is always the soil. Tubers cannot infect each other, so they can be stored together.
Fighting scab
Scab is not easy to spot right away, so it’s impossible to save already infected potatoes. Diseases and pests of other types at least “warn” about their appearance, but it is better to fight everyone in advance using the following procedures:
- Compliance with crop rotation.
- Cultivation in the area of green manure crops.
- Use healthy fruits for sowing.
- The use of acidic fertilizers.
- Careful preparation.
- The use of resistant varieties.
- Regular watering during the growing season.
Alternariosis
The disease has spread everywhere where potatoes are grown. Diseases and treatment of nightshade plants are still being studied more in the southern regions, since in the south there are ideal conditions for the growth and spread of fungi, which can tolerate alternariosis.
Depending on the period, the disease can manifest itself in different ways. Infection begins after rain or thick dew. The spores of the fungus fall into cracks, mechanical damage, or natural depressions. Acid begins to be released, from which the stems rot and die. At low temperatures, development is negligible, but in hot weather, the disease adversely affects the yield. Incubation lasts up to a week.
The first signs are visible on small plants, up to 20 cm high. Later on, dark brown spots appear on the leaves. Under good conditions for development, they can be seen on the third day. Smoky-gray conidia appear a little later. Damaged parts of plants are fragile and soft.
Extruded dark spots of rot appear on the tubers, sometimes even with wrinkles. Eventually, the tubers begin to rot completely, withering and blackening.
Fighting Alternaria
In the southern regions, potato diseases and their control require special attention. There are three ways to protect the crop:
- Agrotechnical . Use only healthy, disease-resistant planting material, observe crop rotation, and remember that early potato varieties are most susceptible to infection. Seed material must be warmed up for the first two weeks at temperatures up to 20 ° C. During storage, ensure that there are no diseased tubers. Alternariosis can be transmitted from one fetus to another. Remove the tops in a timely manner, it is better to carry out desiccation using special means.
- Biological Spray tubers before planting with Integral, Bactofit or Planriz.
- Chemical . The preparations "Ridomil Gold We", "VDG" and "Bravo" will save you from all existing mushrooms, depriving them of comfortable conditions. Before planting, you can also spray potatoes with a solution of the fungicide "Maxim".
Potato diseases and the fight against them, as well as other pests, always require special attention. Harvest directly depends on how well all the requirements are met. The article not in vain gives photos of potato diseases, because the enemy must be known in person.