Potatoes: tuber diseases + photos

There are various potato tuber diseases, most of which are beyond the power of even an experienced gardener to identify at an early stage. From this, the disease begins to spread to other healthy bushes, destroying the entire crop. Many drugs have been invented to treat most potato diseases. However, for them to act effectively, it is necessary to determine exactly what the culture needs to be treated for. In this article we have collected the most common potato diseases, and each of them is accompanied by instructions for combating the disease.

What is the cause of potato diseases?

Most gardeners believe that potato tubers are to blame for diseases pests and weather conditions.They are partly right. However, there is another side to the problem that people rarely admit - this is the fault of the vegetable grower himself.

There are three main causes of potato diseases, the occurrence of which is not caused by pests, but by humans themselves:

• improper selection of tubers for planting;
• violation of crop rotation technology;
• improper care of potato plantings.

Now let's briefly look at each of the problems. What is the incorrect selection of planting tubers? It is clear that affected potatoes cannot be left for planting. But you still need to choose the right varieties. Nowadays a lot of selective potatoes are sold. That is, hybrids. They are immune to most diseases. There are even potatoes whose leaves are not eaten by pests, such as the Colorado potato beetle. But each hybrid is bred for specific growing conditions. If you plant tubers that are not intended for the climatic conditions of the region or the soil is not suitable for them, the immunity endowed by the breeders disappears and the potatoes begin to get sick.

When growing potatoes, it is imperative to observe crop rotation. This is where pests play their bad role. They remain in the ground after autumn harvesting, overwinter, and in the spring they awaken and begin to infect young tubers. Some of them are capable of destroying potatoes at the ripening stage.

Potato plantings are often destroyed by improper care. We missed watering - the crop was depleted in the heat, we overdid it with irrigation - late blight started. Care also involves timely weeding weed, loosening the soil, poisoning the Colorado potato beetle and other activities.

What are the symptoms to determine that potatoes are sick?

The initial stage of crop diseases is difficult to determine even for an experienced gardener. But if you carefully monitor the condition of the plant, you can identify the disease even when the potatoes can be saved. Let's say late blight manifests itself not only on tubers, but also affects the above-ground part of the plant. If the leaves and stems begin to turn black, measures must be taken immediately.

Potato infestation can be recognized by the appearance of aphids. These pests are carriers of diseases. This problem can be avoided by timely weeding and treating the plantings with special preparations.

The main symptom of potato tuber disease is the condition of its tops. A crop affected by any disease begins to lag in growth, the color and shape of the leaves change, and the plant begins to wither. At this stage, you need to dig up one such bush and try to determine the cause of the disease from the tubers in order to choose the right drug for treatment.

Main types of potato diseases

The photo shows a table with examples of common potato diseases. But there are a lot of diseases, so they are divided into three types:

• All types of bacterial diseases are transmitted through planting material, that is, tubers. Moreover, the pathogens overwinter comfortably in the ground. Even if you plant healthy tubers in an infected garden, they will still be affected. Putrefactive bacteria do not die in the heat and even in winter with severe frosts.
• Viral diseases include all types of mosaics. The disease changes the color and shape of the above-ground parts of the plant.The crop may not even die, but very few tubers will form.
• The fungus damages any part of the crop. The most common disease in this series is late blight. It quickly spreads throughout all plantings. If measures are not taken in time, all the potatoes may be lost. Potato fungus is doubly dangerous. In addition to the fact that it itself affects the culture, it additionally kills its immunity to other diseases.

For any type of disease, there are individual control measures. Now we will look at the photo description and treatment of diseases of potato tubers, and we hope that our information will help many gardeners save their harvest.

The video talks about potato ailments and methods of combating common diseases:

Manifestation of bacterial diseases on tubers, and methods of combating them

With a bacterial disease, potato tubers are affected in the soil, and the pathogens are spread along with poor planting material. The crop begins to rot and becomes completely unfit for consumption.

Ring rot of tubers

This type of rot most often destroys tubers. The disease begins to appear on the tops. At the beginning wither leaves, after which the stems fall to the ground. If you cut into an affected tuber, rot can be seen around its circumference. This is where the name of the disease comes from. The causative agent of rot lives for a long time on mown tops, so it’s better to burn it right away.

There is one secret to accurately establish a diagnosis. To do this, break off one stem from a wilting bush and place it in a glass of water. After some time, mucus begins to come out of it.You can dig up the tubers. When cutting even a non-rotten, but affected potato, a yellow formation in the form of a soft ring is visible on the cut.

Rot must be combated at the stage of preparing planting material. It is not advisable to cut large potatoes into several parts. If the tubers are very large, they are cut with a disinfected knife, and the cut site is treated with wood ash. Potatoes purchased for divorce are thoroughly washed and then dried at a temperature of 17^OWith a minimum of 10 days.

You can prevent rot from occurring in your garden by mowing the tops shortly before harvesting. If the disease has already affected the crop, the bush must be dug up immediately, after which it is advisable to burn it.

Damage to tubers by brown rot

This type of rot destroys only tubers. However, the symptom can be identified by the withering aerial parts. The affected bush is severely stunted in growth, and the stems begin to wither.

Affected potatoes can be seen in the garden during flowering. The stems become limp, causing the bush to droop and fall apart. The leaves turn yellow, wrinkle, and dry out over time. There are no methods to combat the disease. There are only measures to prevent the occurrence of the disease. You just need to buy high-quality planting material and also observe crop rotation. In general, it is better to plant varieties resistant to brown rot.

Mixed internal rot of tubers

This disease occurs on mechanically damaged potatoes. As long as the tubers lie untouched in the ground, you don’t have to worry about this disease.When digging up the crop or carelessly transporting it, many potatoes are subject to mechanical damage, through which putrefactive bacteria penetrate. The tubers begin to slowly rot from the inside while they are stored in the cellar.

The only way to combat internal rot is to carefully sort the potatoes before storing the crop for winter storage. The cellar and bins must be treated annually with a solution of copper sulfate.

Wet rot of tubers

The causative agent of wet rot penetrates the potato tissue through the same mechanical damage. Tissue damage occurs during harvesting, but the result is not immediately visible. The potatoes begin to rot in the cellar. Moreover, the disease spreads to other nearby tubers, even if there is no mechanical damage to them.

You can recognize wet rot by feeling the tubers. Potatoes become unnaturally soft. When pressed with your fingers, a light, starchy mucus is released from under the peel. The process is accompanied by an unpleasant odor.

You can avoid the manifestation of the disease if you store the harvested crop in a disinfected basement with good ventilation and dry air. Before going down into the cellar, edible potatoes are sorted, discarding damaged tubers. Before storage, planting material is treated with disinfectants.

Blackleg

This disease most often affects potatoes planted in the place where cabbage grew last year. In the affected crop, the stems near the ground begin to turn black and gradually turn into rot. The tubers begin to become covered with a wet coating, after which they also disappear.

The first manifestation of blackleg can be identified by the yellowness and lethargy of the leaves on the lower part of the plant. Once you grab the thin stem, it will easily be pulled out of the ground. The potato tissue itself acquires a soft structure that emits an unpleasant odor.

The manifestation of this disease can be avoided by careful selection of planting potatoes, plus compliance with crop rotation. In autumn, all dry vegetation must be removed from the garden.

Manifestation of viral diseases and methods of combating them

There are several types of mosaics. Any manifestation of it on potatoes is defined as a viral disease.

Speckled or regular mosaic

The disease appears as yellow spots on the leaves of young potatoes. However, exactly the same signs are observed on the plant when there is a lack of iron in the soil. To make a more accurate diagnosis, it is necessary to observe diseased bushes. If the yellow spots gradually acquire a brownish tint, the plant is 100% infected. The potato bush can only be completely removed, and it must be immediately thrown into the fire. All neighboring unaffected plants are treated with antiviral drugs.

Striped mosaic

There are several strains of this disease. Depending on the pathogen, the symptoms will be different. Although there are common features that allow us to identify the virus. Firstly, the fragility of the plant increases. The stem breaks when lightly pressed by hand. Secondly, stripes and dots of different colors appear throughout the plant. The back side of the leaves becomes brown.

The virus spreads instantly, leaving no chance for neighboring potato bushes to survive.The affected plant must only be removed from the garden and burned in a fire.

Wrinkled mosaic

By the name of this virus, you can already determine that potato leaves begin to wrinkle. Yellow spots appear in some areas. The result of the epidemic is a large loss of crops.

Wrinkle mosaic virus progresses only during hot, dry summers. This does not happen every year, and only under favorable weather conditions for the pathogen.

rustling mosaic

This type of virus is also called leaf curl. Infected potatoes cannot be immediately identified. Symptoms are observed in the second and third years of growing the same variety. Every year, potato bushes become shorter. In the third year, the leaves of diseased plants curl into a tube from the edges to the central vein. Over time, they acquire a bronze tint and become fragile. If you run your hand over such foliage, it will partially begin to crumble, making a rustling sound. Simultaneously with the above-ground part, the root system is affected. This leads to the formation of small tuber ovaries or none at all.

Since identifying the virus at an early stage is almost impossible at home, it is better to start a different potato variety from healthy planting material next year.

Manifestation of fungal diseases and methods of combating them

The fungus quickly attacks the tubers and above-ground parts of potatoes, penetrates neighboring plants through mechanical damage, and instantly spreads throughout all plantings. The harvest can only be saved by timely identification of the disease and rapid adoption of appropriate measures.

Late blight

Late blight spreads instantly across a potato field.If you remain inactive in the fight against this fungus, all healthy bushes will disappear in a couple of weeks. The first sign of the appearance of a fungus is brown spots on potato leaves, gradually growing over the edges with a white coating. The disease spreads from leaves to stems and tubers. Its further manifestation depends on the weather. If it’s hot outside, the above-ground part of the potato simply dries out. In a damp, rainy summer, the tops affected by late blight simply rot.

The carrier of late blight is water. It doesn’t matter whether it’s rain or artificial irrigation, but along with drops of water, fungal spores are spread and settle on the stems of healthy plants.

There are several preventive measures to help avoid late blight. Firstly, the planting material must be germinated and processed before planting. After germination, the grown potato bushes are hilled into high mounds. Secondly, you cannot grow potatoes in the same place every year. In addition, tomatoes are not the best neighbor in the garden.

Copper sulfate is used to prevent late blight. When the potato bushes grow to 20 cm in height, they are sprayed with a solution prepared from 10 liters of water and 10 g of blue powder. If the disease has already been noticed on the plants, then a 1% solution of Bordeaux mixture is used to treat the potato plantings. For one hundred square meters of garden, 4 liters of solution are consumed. Spraying is performed 4 times with an interval of a week between each procedure.

The video talks about protection against late blight:

Common scab

The spores of this fungus persist for a long time on mown potato tops and other vegetation. The disease most often affects potato varieties that produce tubers with red thin skin.Corky, cracking spots appear on the surface of the potato. Such damage to the shell opens the way for other pathogens that cause rot to penetrate into the pulp. In practice, it has been found that the disease most often develops in areas with sandy or calcareous soil.

Resist common scab Preventive measures help. The planting material is germinated before planting in the light so that the skin of the tubers acquires a greenish tint, but even before this they are treated with formaldehyde. Good results are obtained by sowing green manure and observing crop rotation. It is better to plant varieties that are resistant to scab. If you still want to grow your favorite variety of red potatoes, then for planting you need to choose an area with slightly acidic soil, and plant the tubers themselves shallowly.

Silver scab

The manifestation of the disease on potato tubers can be recognized by brown spots with a silver edge. During storage in a damp cellar, the skin of the affected potatoes partially peels off.

The peak development of silver scab is the period of tuber ovary in hot weather. Moreover, most often this happens in areas with sandy loam or loamy soils. In the fall, when selecting planting material, care must be taken to ensure that affected tubers do not fall into the planting area.

To combat the disease, the drugs Fundazol or Botran are used, which are used to treat the tubers before planting. After harvesting, the potatoes are dried for about three days, and only then are they lowered into the cellar. The storage facility is treated annually with preventive solutions.

Powdery scab

The disease affects the bottom of potato stems, the root system and the tubers themselves.The disease progresses during rainy summers and can be identified by white growths on plant stems. To be sure, you need to dig up one infected bush. The roots of such potatoes will also have a white growth. Over time, the white formations turn into dark, cracking spots. Powdery scab spores retain their vital activity in soil, tubers and even manure.

Measures to combat the disease are almost the same as for any other type of scab. The main thing is not to throw out affected potato tubers to rot in compost heaps. The fungus does not die in manure, and when fertilizing is applied, it spreads throughout the garden again.

Cancers

This disease has a limited distribution sector, but is very dangerous because the pathogen persists in the soil for a long time. Most often, the disease occurs in private small gardens, where potatoes have been grown in the same place for years. Moreover, potato varieties susceptible to cancer are affected.

The first signs of the disease are the appearance of growths on the lower part of the plant. The objects affected are leaves, stems and tubers of potatoes. Over time, the growths begin to darken, and, having reached a black color, open up during rotting. From cancerous formations, many mature spores fall into the ground, where they continue their life activity.

Spores persist in the ground for more than twenty years. Together with the soil, they stick to healthy tubers and are carried to neighboring areas by melt water, the feet of domestic animals, birds, and so on.

The spread of the disease can be stopped by growing potato varieties that are resistant to cancer. Moreover, it cannot be planted next year where the outbreak was located. It is better if other crops, for example, beets, beans or sunflowers, grow in this place within five years. Before planting, lime is added to the soil, but in reasonable quantities. Otherwise, when growing potatoes in the future, there will be a problem with scab. If the size of the garden allows, then dangerous areas can be left fallow.

Dry rot of tubers

This fungal disease does not appear on growing potatoes. Dry rot forms on tubers stored in the cellar. This process usually begins two months after harvesting. Fungal spores persist in the soil for up to six years. They, along with the soil, stick to the potato tubers, after which they end up in the cellar. The life activity of pathogens continues on the walls of the storage facility if it is not disinfected before storing the crop.

Potato tubers become infected with dry rot only through mechanical damage to the skin. It doesn’t matter whether it’s on the field or in the cellar. Spores can be carried by rodent pests. First, gray spots appear on the skin of the potato, which over time acquire a brown tint. The pulp under the affected areas begins to rot and dry out. The potato becomes wrinkled, hard and very light. White growths appear on the rotten skin. It is in them that new fungal spores are formed, which, after ripening, infect healthy potato tubers.The optimal conditions for the development of fungus in the cellar are a high humidity concentration of about 90% and an air temperature above 5 °C.

In the fight against this disease, all measures used to combat other diseases are justified. You should also try to cause as little mechanical damage to the tubers as possible. An important activity is the disinfection of the storage facility where the potato tubers will overwinter. Before planting the crop, the cellar is treated with a solution consisting of 10 liters of water, 100 g of copper sulfate and 2 kg of lime. Secondary disinfection is carried out with a fungicidal spray. Among the folk methods, good results are obtained by burning dry wormwood stems in the cellar. When laying potatoes in the bin, dry rowan leaves, elderberries or onion peels are scattered between the tubers.

Conclusion

Most common potato diseases can be avoided if you promptly treat the plantings with pest control drugs, observe crop rotation and preventive measures. When breeding new potato varieties, planting material should be purchased only from trusted companies.

This video will help the vegetable grower learn how to process potato tubers before planting:

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