The most dangerous potato diseases and the fight against them

The most dangerous potato diseases and the fight against them

Potatoes are very popular among even the most sophisticated gourmets. And although this is a simple vegetable, which is not uncommon, it also cannot always please summer residents, since it is attacked by diseases that can significantly reduce yields.

The most common potato diseases and methods of dealing with them

Further, we will talk about the most common diseases and pests that like to profit from potatoes and how to quickly and easily get rid of them.

Late blight

Late blight is one of the most insidious diseases, which can destroy 15% of the total potato crop.

Its appearance is caused by lower fungi such as oomycetes. If microorganisms are present in the soil, then the likelihood of contracting this disease is very high.

In addition, such mushrooms are very fond of moisture, because summer rain and temperatures above 15 degrees will perfectly help their spread.

It is not at all difficult to detect signs of late blight, since the leaves begin to turn black, and from below you can see white spores on them, which indicates the presence of fungi.

The difficulty is that wind and rainwater can easily spread these spores on the field. The tubers turn black and pose a great threat to neighboring bushes.

To avoid infection, you must adhere to the following precautions:

  • potatoes should be planted in the same place for no more than 3 consecutive years;
  • it is better to land on a plain, as well as in a sunny and well-ventilated place;
  • should keep the distance between the bushes;
  • do not plant already affected seeds;
  • before planting, the potatoes must be thoroughly dried in the fresh air at a temperature of 18 degrees for 2 weeks;
  • so that the tubers are resistant to disease, they are processed Immunocytophyte or Agatom-25K.

Common types of scab

Potatoes also suffer from 3 types of scab: black, powdery and silvery.

Black scab

As it is also called rosoctoniasis, it can cause a lot of trouble for summer residents. The disease affects tubers and tops.

In the early stages, due to scab, stop growth potatoes, and over time, the culture will die altogether. The disease manifests itself in the form of black spots that resemble sores.

Excellent conditions for the development of black scab are high humidity and an air temperature of at least 18 degrees.

How to get rid of rosoctonia disease, you will be prompted by the following tips:

  • do not plant infected tubers in the ground;
  • do not sow in the same place for several years in a row.
  • if the soil is affected by black scab, then it should process the planting material with Prestige or Maxim.


Also infects leaves and tubers. Red sores can be seen on the potatoes, which eventually destroy the plant. The disease is transmitted by air or through humus, or chicken droppings.

To combat this ailment, a special solution is used, for the preparation of which they take:

  • 10 liters of water;
  • 3% bleach;
  • 5% copper sulfate.

For watering use 300 ml for each bush.


An insidious disease that can dry out the stem or the tuber itself. It manifests itself in the form of silvery spots that can cover almost 50% of the surface.

A disease that is suitable for a temperature of at least 3 degrees Celsius and an air humidity of at least 80%. And spores live in tubers for a very long time, since they can easily tolerate even cold.

In the fight against this disease, tools such as:

  • Maksim, they are treated with tubers 3 days before planting and dried well in the sun.
  • Quadris, which is applied to the plant just before planting.


The L-virus is one of the most insidious viruses, affecting about 30% of the potato crop. There are 2 ways of transmission of the virus: aphids and contact with infected plants.

The symptoms of the disease depend on the variety and growing conditions. This can often be wrinkles, blemishes, or leaf dieback.

To eradicate the virus, you must:

  • do not use infected tubers as planting material;
  • to conduct a continuous fight against aphids and cicadas, in which such means as Aktara and Karate Zeon.


The wireworm, the larva of the click beetle, is no less troublesome for gardeners. In April, the beetle makes its flight and lays eggs in the soil, therefore there is no place that would not be affected by it. However, it is imperative to control its population, otherwise it can lead to disastrous results.

Potatoes affected by wireworm cannot be stored for a long time, since it will quickly start to rot.

A favorite habitat for the wireworm is wheatgrass rhizome, dense thickets and acidic soil.

To reduce the population of these beetles, you should adhere to the following rules:

  • it is necessary to change the landing site every 3 years;
  • in spring and autumn, you should dig up the soil to kill the larvae;
  • do not leave tops and tubers for the winter on the site, since they will help the wireworm and larvae to endure the winter well;
  • plants should be planted in the garden that perfectly scare off these beetles. These include marigolds, which emit a hateful smell for the wireworm, and legumes, in the rhizomes of which there are bacteria, which secrete nitrogen, which is terrible for the beetle.
  • You can also use the folk method. To do this, 100 g of celandine is insisted for 3 days in 10 liters of water, and then the bushes are watered.

Also, to get rid of the wireworm will help and all kinds of bait:

  • On 1 m2, you should dig in a jar, on the bottom of which you put cut potatoes. Beetles will definitely get into it. Just remember to check the jars and kill the bugs every 3 days, as well as change the bait.
  • You can also bury the tuber in the ground and set a stick for marking and repeat the above procedure every 3 days.
  • In the spring on the site you can cover cellophane and grease it with a sugar solution... The beetles will surely flock to the scent and stick to the trap.


One of the worst parasites is the nematode. The roundworm, 2.5 cm long, is capable of destroying 80% of the crop. The worms dig into the root of the potato itself and nutrients do not enter the tubers, therefore they grow small or do not form at all.

This worm is able to catch up with real horror on gardeners, since it is practically invulnerable:

  • he does not care about high or low temperatures;
  • he is easy tolerates drought and flood.
  • even a lethal dose of radiation for humans is powerless against this worm.

In addition, the parasite is capable of multiplying very quickly.

It will take decades to get rid of the nematode, and the population can be reduced in 2 years.

In the fight against a nematode, the following measures are used:

  • Quarantine is announced, and potatoes are not taken out of the region.
  • This crop is not planted in the same place for more than 3 years in a row.
  • After 2 years, it is desirable to change the planting material.
  • The soil treated with urea.
  • Before planting, the tubers are watered with a solution of potassium permanganate, at the rate of 0.5 g per 10 liters of water.


Symptoms are clearly visible 20 days before flowering, when the leaves are covered with brown spots. As a result of damage, spots are also visible on the tubers.

Alternaria or brown spot affects both the tubers and the stem of the plant. Infection occurs through wind, insects and raindrops. Hot and rainy weather is ideal for the spread of this disease.

To prevent disease, tubers are treated with drugs such as Integral or Agat-25... Young shoots are moistened with Bravo.


Black leg is another disease that has pronounced symptoms. With such a defeat:

  • leaves turn yellow, curl up and dry up;
  • roots and tops first turn black and then rot;
  • they are easy to pull out of the soil.

If the disease progresses rapidly before or during flowering, then tubers will not form.

A rainy summer is a favorable condition for the black leg. Colorado beetles, aphids and cicadas are carriers of this disease.

To combat the black leg, you should adhere to the following precautions:

  • do not use infected tubers and soil for planting;
  • diseased bushes are pulled out and burned, or buried 1 meter, sprinkling with bleach.
  • harvesting is carried out in dry weather;
  • before hiding the crop in the basement, it is well dried;
  • the storage is treated with a 3% lime solution;
  • processing potatoes before planting also helps a lot Maxim or Fitosporin.

Potato cancer

This is a disease caused by a fungus, in the place where it enters the plant, a growth is formed.

Is carried over disease very easy:

  • rain water;
  • with a person's shoes;
  • various insects;
  • if the animal eats the affected plant, then it comes out with the manure and continues its vital activity.

To exterminate this type of mushroom, you must:

  • constantly change the planting site of the culture;
  • grow cancer-resistant varieties: Early yellow, Savory, Sparkle and many others;
  • the tubers are treated with a 1% suspension of the foundation.

Potato pests

The most common pests that do not mind eating potatoes include:

  • Colorado potato beetle;
  • potato moth;
  • bear.

Colorado beetle

Actively destroys the stem, due to which tubers cannot develop normally... It multiplies rapidly; in 1 season, 2 to 3 generations of Colorado beetles are born, which are in a hurry to fill their belly.

To exterminate the Colorado beetles, it is imperative to collect both the insects themselves and tear off the leaves with their masonry and throw them into a container filled with kerosene.

Potato moth

Cute white butterfly. Over time, it turns into a caterpillar and gnaws out almost all the tuber under the skin itself and leaves its excrement at the same time.

She also can also settle in the stem of plants... It only takes a month for a new generation to appear.

To reduce the number of caterpillars, you must:

  • 2 weeks before harvesting, mow the tops;
  • use a remedy such as 10% carboros. 90 g of this agent is dissolved in 10 l of water.


It is not so easy to find her herself, since she lives underground, but it is still possible to outwit her.

We get rid of the bear: they set up a simple trap by digging a hole half a meter deep and pouring horse manure into it. Medvedka will certainly want to settle in it to spend the winter. When the cold comes, it is necessary to scatter the manure, and find and destroy the insect itself.

You can also water the places of its distribution. 10% karbofos, 50 g diluted in 10 liters of water.

Varieties of potato rot

No less dangerous is a disease called rot. There are several types of rot:

  • annular;
  • brown bacterial;
  • mixed internal;
  • wet;
  • dry.

Very often there are cases when ring rot and brown rot are confused. Although they are caused by different types of bacteria, similar brown-yellow spots appear on the leaves. However, if the vessels are squeezed, then with ring rot a light yellow mass will appear, and with brown rot, the ring turns brown.


Doesn't live in soil, she passed on to the next crop through seeds... Also, if you put the affected tubers in storage next to healthy ones, the bacteria will penetrate through scratches or damaged skin.


May lurk in the soil and wait in the wings to penetrate the damaged tubers.

Mixed internal

Mixed internal rot of potatoes occurs as a result of mechanical or bacterial damage, as well as due to a variety of diseases that initially damaged the tubers. Be responsible for the choice of planting material!

In order to avoid the appearance of all the above types of rot, you should first of all:

  • regularly change the planting material;
  • change the landing site;
  • after harvesting, burn the tops;
  • avoid mechanical damage to potatoes.


Can completely destroy the entire tuber in 15 days... This disease manifests itself during storage. Most often, at the site of mechanical damage, the surface becomes soft and begins to rot.

It is impossible to chemically overcome wet rot. In order not to expose potatoes to this disease, you should:

  • dip well-dried tubers into the storage;
  • process the cellar with copper sulfate or lime;
  • avoid mechanical damage and freezing of tubers.


Dry rot of potatoes can destroy 20% of the crop... It can affect plants at any time, both during storage and in the soil. Its peculiarity is that it is not treated, but can only hide for a while.

Bushes affected by this disease wither, slow down in growth, or disappear altogether.

To avoid its appearance, you must:

  • do not overuse fertilizers, as they emit nitrogen, which is beloved by this rot;
  • remove tops from the garden;
  • change the landing site and planting material.

Potato mosaic

Mosaic is an equally unpleasant disease that is caused by viruses. There are 2 ways this disease is transmitted:

  • various insects;
  • if you treat an infected plant with a tool, and then apply it to a healthy one, then infection is definitely inevitable.

Particular attention should be paid to wrinkled and striped mosaics.


It got its name according to the manifested signs of the disease. The leaves begin to wrinkle and curl inward. In addition, diseased cells cannot retain moisture, which is why the most a slight drought leads the plant to death.

Banded Mosaic Virus

More aggressive and can destroy about 90% of the crop. First, stripes appear on the vessels of the leaves, then the leaves die off, and only a few of them remain on the whole bush. As a result, the tuber stops growing altogether.

There are also methods for dealing with mosaics:

  • the virus of this disease dies at 60 degrees;
  • Infected tubers should not be planted, and their easy to see in ultra light;
  • sprouted tubers should also be selected, since the sprouts of infected tubers will be weak;
  • before planting, seeds should be treated with insecticides.

Potato diseases: classification

All potato diseases are divided into the following groups:

  1. during storage;
  2. viral;
  3. mushroom;
  4. bacterial;
  5. non-infectious.

Table 1... Separation of potato diseases by types.

Disease typeDisease


all kinds of mosaics

folded leaves

corymbose apex

curly dwarfism

post wilt


Late blight

fusarium dry rot

black scab


ring rot


wet bacterial rot

common scab

mixed internal rot


darkening of the pulp

gray spot or melanosis

strangulation of tubers

heat damage to tubers

freezing tubers

glandular spot

hollowness and deformation of tubers

red or blue coloration of the tuber pulp

reticularity of the rind

All these diseases can develop both during the period of potato ripening and during storage.

Why are there brown spots on potatoes?

By cutting the potatoes, brown spots can be observed that will never rot. We answer the question why this is happening - it is gelatinous spotting. Such potatoes simply become hard and starch grains are destroyed in it.

These spots are caused by:

  • low humidity;
  • heat;
  • lack of phosphorus.

Is developing this disease only during growth, when storing potatoes, it freezes.

To prevent this disease from affecting your potatoes, it is necessary to apply nitrogen fertilizers, lime and water the potatoes.


Today, there are many insecticidal products that will rid your potatoes of diseases and all sorts of pests. The most effective of them include the following funds:

  • Maksim - protects against many diseases, and especially against all sorts of scab and phyto-infection.
  • Quadris - a remedy that not only protects against many diseases, but also improves the growth of potatoes.
  • Cruiser - excellent protection of tubers from various pests.
  • Celeste Top - protects tops and tubers from pests, as well as from fungal diseases.
  • Aktara - will provide protection for potatoes for 60 days.
  • Force - aims to destroy wireworms.
  • Prestige - protects late varieties from rot, scab and Colorado beetles.

And also such drugs as Imidor, Commander and Tabu should be noted.

As you can see, no matter what disease or pests try to destroy your crop, they will still fail if you properly care for your favorite potatoes. Therefore, fight diseases and pests in time and you will achieve amazing results. Have a nice harvest!

Potato diseases and their biological treatment

Potatoes are the most common vegetable crop on the land plots of many summer residents and gardeners. At first glance, it may seem that growing a potato crop is easy enough. But it will not work just to bury the tubers in the ground in the spring and forget about them until the fall. With such "care", you can lose a significant part of the harvest, since potatoes, like other vegetable crops, are often affected by various diseases and pests.

Firstly, you need to properly prepare the site on which the potatoes will be planted and, secondly, prepare the tubers themselves, because good healthy planting material is the key to getting a plentiful high-quality harvest.

Potato protection from diseases is carried out throughout the growing season. In the complex of protective actions to combat various infections, as an auxiliary prevention of potato disease, treatment with biological products is carried out: Mikosan, Fitodoctor, Fitosporin, Trichodermin, Gaupsin, Planriz. The activity of these drugs is aimed not only at ensuring a high protective response of plants to a wide range of diseases, but also at activating their own resistance, stimulating growth, resistance to frost or drought. Planned preventive treatments of potatoes, for example, with Mikosan, are recommended to start when the first shoots appear, then at the beginning of budding and after flowering. And when the first signs of disease are found, biofungicides based on living microorganisms should be used: Phytodoctor, Fitosporin, Trichodermin. If you systematically apply preventive measures to combat diseases, you can forget for a long time what potato diseases exist and how to treat them in order to preserve the harvest.


Every year in the middle of summer we observe black cherry orchards, as if they were walked with napalm. It is not in vain that this terrible disease is in the first place in our rating. It wiped out the cherry harvest. Affected and the rest of the fruit. It's all the fault of the mushroom of the genus Monilia. Hibernating on infected debris, mainly on fruits, it begins to actively dust in the spring. Small spores, picked up by the wind, are carried for kilometers. Getting on the pistil of a flower, they germinate inside the shoot, clog the vascular system, which leads to a violation of the conductivity and death of the shoot. The disease manifests itself in two forms: monilial burn (on shoots) and monilial rot (on fruits).

You can start fighting it now. Be sure to remove all fallen leaves and fruits on the eve of winter. But the most important treatment will be in the spring: at the beginning and in the middle of flowering, treat the trees with a systemic fungicide based on cyprodinil.

In summer, at the first manifestations of the disease, if possible, cut off the damaged shoots with the capture of 5-10 cm of healthy tissue. And treat the plants with 1% Bordeaux mixture.

What are the differences between viral diseases in potatoes

Potato viral diseases are the most severe. They spread more easily and faster than bacterial ones. They are not amenable to any treatment. They are also inherited.

Basically, these are diseases of potato tops. The tubers themselves can simply become carriers of viral strains, but they are suitable for food.

For your information! Viral diseases have less vivid symptoms than bacterial or fungal, but the crop is ruined even in greater volume.

Causes, symptoms and treatment

PLRV is sometimes also referred to as leaf roll virus. He is one of the most dangerous. The virus first infects the leaves of the potato, no treatment is expected, only the physical destruction of the bushes.

The disease significantly reduces the yield of potatoes. The main cause of infection is the bite of an aphid, which is the carrier of the virus. The virus also spreads along with the affected tubers.

Signs of a viral disease:

  • curling the leaf along the midrib
  • leaf plates become brittle, brittle
  • sometimes the sheets turn red around the edge
  • there are areas with dead tissue inside the tubers.

Virus Y is a disease that is recognized only by the summer resident who has experience in growing root crops. Such a virus causes a wrinkled mosaic, that is, the appearance of pimples and swellings on a young leaf blade. But this is clearly manifested only in the 3rd year. It is carried by aphids, and also spreads along with infected planting material.

  • the infected bush grows slowly
  • curly tops are present
  • falling stems to the ground
  • very small tubers.

For your information! Virus X is dangerous because a diseased plant can look like completely healthy. But at the same time, the tubers will not form normally, the yield will decrease by at least a third, or even more.

Fungal diseases of potato tops, photos, description and treatment

A detailed description of each disease of the potato tops in pictures and photographs will help you easily determine what exactly the plants are sick with, and quickly navigate the methods of struggle. Timely treatment and careful prevention will help preserve the harvest.

Potato late blight: photo, description and treatment (Latin Phytophthora infestans)

The causative agent of this potato disease is the oomycete fungus Phytophthora infestans de Bary. Starting with the foliage, the disease gradually affects the entire bush and destroys the tubers. Most often late blight develops in the second half of summer, when the heat subsides, and the night air temperature is from plus 12 to plus 15 grams. Celsius.

The disease is easy to recognize by the following signs: brown and brownish spots appear on the leaves of plants, a white bloom forms on the lower side of the leaf, in rainy weather the entire potato planting is covered with spots in a matter of days.

Potato late blight, photo, description and treatment of the disease

It is easier to prevent late blight of potatoes, treatment can be not only costly, but also useless. The main preventive measures are: healthy planting material, germination of tubers before planting - this will reveal the disease at the first stage. Observance of crop rotation is important: you should not grow potatoes in one place for several seasons in a row, proximity to tomatoes is not recommended. Bushes should be well spud, tubers should not lie on the surface.

The disease can be prevented by prophylactic treatment of planting with copper sulfate (10 grams per 10 liters of liquid). The procedure must be carried out when the tops reach 20 cm in height.

When the first signs of the disease are detected, the bushes are sprayed with 1% Bordeaux liquid. It is recommended to observe the consumption rate: 4 liters of mixture per 100 sq.m. The procedure is carried out up to 4 times, with an interval of 10 days. You can also use the highly effective drug Arcerid, this will allow you to neutralize the disease in the shortest possible time and save the harvest.

Treatment of potato bushes from late blight

There are many herbal and ecological remedies that prevent many potato diseases, and combating them with folk methods brings good results without harm to the environment. You can prepare a garlic solution: 0.2 kg of fresh crushed product is poured with a liter of water, and insisted for 2 days. The strained infusion is diluted with clean water to a volume of 10 liters, and the bushes are sprayed.

You can also use iodine. Just a few drops on the sprayer container will help protect the plants. Treatment with such substances must be carried out throughout the season every week, without getting on the flowers. Most often, early ripening varieties suffer from late blight, mid-ripening varieties are more resistant to it: Luck, Reserve, Lugovskoy.

Alternaria spp.

For every gardener who grows potatoes, photo diseases of the tops, and their descriptions, make it possible to recognize such a disease as Alternaria in time. The defeat of this fungus can be recognized by the presence of brown, rounded spots on the leaves. A similar disease can be detected in early July, when the affected areas dry up and crumble, streak-like spots and stripes appear on the stems.

Potatoes - leaf diseases, photos of Alternaria

The fungus of the genus Alternaria solani actively develops in humid weather and moderate air temperatures up to plus 20 grams. Celsius. Such potato diseases are effectively treated with the fungicides Fulicur and Prozaro. It is necessary to use drugs strictly according to the instructions. Among the popular methods of struggle, the most effective is the treatment of planting with Bordeaux liquid.

The main measures for the prevention of Alternaria is planting on a flat surface of soil without lowlands, where moisture accumulates, creating favorable conditions for the reproduction of the fungus, as well as maintaining crop rotation. It is also recommended to remove from the soil and utilize plant residues and use disease-resistant varieties: Adretta, Bronnitsky, Lyubava.

Potato diseases: photo, description and treatment video

Potato diseases: scab in the photo, description and treatment

Most often, it is young tubers with a fragile skin that are affected by scab. It manifests itself as follows: scabs and ulcers can be seen on the tubers. Of course, these potatoes lose their attractive qualities. Moreover, its taste also deteriorates.

It is worth remembering that some factors can favorably affect the development of the disease, for example, sultry weather, the introduction of lime or fresh manure into the ground. But how to deal with the scab on the potatoes? Of course, it is important to pay attention to the photo, the description of the disease and the signs of its manifestation. Then summer residents carry out a number of the following actions, among which there are preventive ones:

  • regular watering of the crop during prolonged drought
  • liming exclusively in autumn
  • spraying tops with the Zircon growth circulator
  • culling damaged tubers
  • planting material in a well-heated ground
  • treatment of tubers with boric acid solution.

Novice summer residents sometimes do not know that there are several varieties of scab, including silver, powdery, black. This means that control measures may differ slightly.

Common pests of potatoes

There are more and more complaints that potatoes are poorly stored and that someone else and something claims it at the same time as a person.

In addition to the fact that potatoes are highly degenerate, they are damaged by non-parasitic diseases, and pests have recently become more active. In addition to the Colorado potato beetle, the potato moth appeared and actively harms during cultivation and storage.

This common and very dangerous quarantine pest of potatoes severely damages stored food and seed potatoes and makes them absolutely unsuitable for nutrition and even more so for reproduction. Damage to potatoes occurs at elevated temperatures, so it is better to store seed planting material until germination or warming up at a temperature of no higher than 3-5 ° C. At higher temperatures, the potato moth multiplies very quickly (gives 3-4 generations), and by the end of the storage period, only dust remains from the tubers.

These photos show what the moth pest looks like:

If signs (exudation of tubers) are detected by potato moths, potatoes should be treated only with biological preparations (for example, "Lepidocide").

Most dangerous, the potato moth is hard to spot. Therefore, against this harmful pest, it is necessary to carry out proactive spraying with such systemic drugs as "Aktara" or "Apache" with strict adherence to waiting times. For the treatment of potato planting material from pests, it is permissible to use the Prestige preparation, which protects potatoes throughout the growing season from most soil and other pests. When potatoes are infected while still in the field, the potato moth (caterpillar) causes the main damage in the basement, where the potatoes are stored all winter. The caterpillars of the potato moth gnaw holes in the tubers starting from the eyes and pass in the surface layer of the pulp. The peel over the passages dries up and shrivels, excrement entangled in cobwebs accumulates at the inlet.

Wireworms are also the main pests of potatoes. These are the larvae of click beetles, which lead a secretive way of life, live and develop in the soil for 3-4 years. They bite into tubers, roots, damage underground, parts of many plants.

The larvae of these insect pests of potatoes live only in moist soil and, when the upper layers dry, go into deeper soil layers.

Due to their secretive lifestyle, the fight against wireworms is very difficult. The use of chemicals in household plots is undesirable from an environmental point of view. The list of drugs for controlling soil pests of potatoes is extremely limited, not many are allowed, for example, such as Provotox, Zemlin or Pochin. And here every amateur gardener should know that when using chemicals, root and bulbous vegetable plants cannot be planted, for the rest of the green there are waiting times that must be observed. The use of biological agents to protect potatoes from pests is generally ineffective. It follows that only agrotechnical measures can solve the problem.

Liming contributes to the decrease in the number of wireworms, provided that the soils are acidic. Weeds are eliminated on any soil, and first of all, creeping wheatgrass.

Wireworms are considered one of the most dangerous pests not only of potatoes, but also of other tuber crops. Before planting potatoes, wireworms can be caught in the area using baits from slices or small potato tubers with wire rods stuck in them. The baits are buried in the ground to a depth of 5-7 cm every 0.5-1 m. And after 2-3 days, the baits are removed and the larvae are selected from them. And, finally, to control these pests of potatoes, you can use such a measure as manual sampling of yellow wireworm larvae when digging and loosening, and poultry can be attracted to chicken owners for this purpose.