It is impossible to find a gardener who has never encountered potato diseases and pests. Gardeners go to great lengths to save their crops - they plant vegetables in barrels and bags, store tubers under hay, and even grow potatoes in a bag. Potato diseases and the fight against them take quite a lot of time and effort, if you do not know a clear algorithm for the necessary actions. Numerous fungi, viruses and bacteria still infect both the plant and the mature crop. So what is the reason and how to deal with this scourge? Description of potato diseases, treatment, photos - all this is presented in the article. As you know, the carriers of most diseases are pests.
Classification of diseases
Unfortunately, it is impossible to get rid of a single disease instantly even with the strongest chemical preparations or with the help of the complete destruction of the plant. This is due to infection not only of mature tubers, but also of the soil, as well as plants at the stage of planting material. That is why it is important to know how to treat potatoes for diseases before planting and how to recognize a particular disease. ATDepending on the nature of the disease, a specific treatment is applied. There are three main types of potato diseases:
- Bacterial - black leg and rot: brown, ring, wet, mixed internal. These diseases of potato tubers are provoked by the action of microbes that spread from the stems throughout the plant. It is rather difficult to deal with them, since not only the plant, but also the soil in which it grows needs to be processed. One of the measures to combat potato diseases of bacterial origin is the timely sowing shift.
- Fungal - potato cancer, late blight, phomosis, fusarium, Alternaria and scab: common, powdery, silvery, black. This group is considered the most dangerous. Most often, fungal diseases occur due to pests or improper plant care.
- Viral - tuber necrosis, tuber gothic, mosaic: common, wrinkled, banded. These diseases are carried by pests such as aphids, cicadas, and Colorado potato beetles. In the first few years, the results of their vital activity are almost imperceptible, but every year more and more plants become infected, which gradually die.
In the following sections we will give a more detailed description of potato diseases (with photo). Tuber treatment will also be considered.
Brown bacterial rot
The disease is caused by the vital activity of microorganisms Ralstonia solanacearum. The first signs of infection appear during flowering and tuber formation. potato diseaserecognizable by yellowing and withering leaves, which become wrinkled and lifeless. The stems begin to fall down and change from green to brown. With the active reproduction of bacteria, softening and decay of the root part of the stem occurs. The sprouts gradually split and the veins turn rotten brown.
When cutting off a diseased stem, you can find dark fibers, when pressed, a grayish muddy mucus will be released. The death of the bushes occurs due to clogging of the veins with a gum mass, which has a high density. Thus, brown bacterial rot can be attributed to vascular diseases of potatoes. On tubers, the disease looks like a softened vascular ring and a large number of brown spots in the core. Rotting of tubers begins during the storage of the crop. The process is accompanied by the release of mucus and an unpleasant odor. The affected tuber completely rots and infects neighboring ones.
The fight against the disease is the organization of crop rotation and the introduction of certain drugs. In addition, you can plant potatoes on an infected bed no earlier than five years later. Seed tubers are carefully sorted before planting and placed in a warm place for 3-4 weeks. Such a procedure will determine specimens suitable for planting. To cut the planting material, only a clean and disinfected knife is used, and he althy tubers are treated with "Baktofit", "Rizoplan" or "Polycarbocin" for prevention purposes.
Ring Rot
Signs of infection with the disease are clearly visible in the photo of a potato tuber. The manifestation of signs of the disease begins after the end of flowering. Thin shoots begin to turn yellow, and the leaves curl. Infected parts of the plant are not so easy to pull out due to the destruction of the sinewy structure. Since the disease begins its development from the roots, it is too late to determine the infection. Cutting the tuber, you will see rings at the edges of the core, which are yellow or brown. By clicking on the affected area, you can notice the release of gray-yellow mucus. When planting such tubers, you will get a weak crop with deformed leaves and thinned stems.
This disease occurs when fruits are mechanically damaged during planting, storage conditions are violated, and poor-quality planting material. To date, there is no drug that can overcome ring rot. You can fight it with the help of seed shifts, the introduction of potash and phosphorus supplements and the regular destruction of diseased plants at the slightest sign of infection.
Wet rot
This disease is quite difficult to detect in the early stages, since the main blow falls on the core of the tubers. The cause of the development of wet rot is bacteria that enter the root crop when damaged, and are also carried by pests. Potato disease manifests itself in the form of severe softening and rotting of the tuber. At the same time, a very unpleasant and pungent odor is emitted. Decaying tissues are first white, then turn brown and almost black. Moreover,the skin until the last retains its integrity and attractive appearance. In some cases, dark dents may appear on its surface, when pressed, a whitish liquid flows out. At the slightest sign of damage, the tubers are removed from the total mass of the crop in order to provide the rest of the potato with protection from diseases and pests. Experienced gardeners have noticed a pattern between freezing or excessive overheating of potatoes during storage and its subsequent infection with wet rot.
But how to prevent its development and protect your crop? In this section, we will tell you how to treat potatoes from the disease.
After harvesting, specimens intended for further planting and cultivation are treated with the Maxim chemical preparation. In addition, try to protect the roots from mechanical damage and insects.
Mixed internal rot
The causes of this disease are no different from other bacterial diseases - improper storage, violation of the temperature regime, mechanical damage - all this provokes the development of harmful bacteria. Symptoms appear depending on the type of bacteria that enter the tissue membranes of the root crop. At the same time, signs of both ring rot and brown rot can be observed. In addition, a gray, pinkish or brown coating appears on the affected areas.
The fight against mixed rot is carried out by treating tubers with Fludioxonil and Maxim. seed material forfor propagation of potatoes, before being sent to storage, it is sprayed with any antibacterial preparation.
Black leg
A fairly common potato disease caused by bacteria of the genus Pectobacterium, which settle on a variety of weeds and move to cultivated plantings. These parasites are incredibly hardy - they survive at temperatures from +2 ° C to +32 ° C, and they can be stored in the soil for several years until favorable conditions occur. Unfortunately, it is impossible to determine the infection in the early stages. The rapid development of the black leg occurs with high humidity or hot weather. Signs of infection appear both on the tubers and on the aerial part of the plant: the stem begins to rot, the leaves turn yellow, and the tubers turn black and rot.
In hot weather, a week after infection, the basal part of the stem rots, causing it to fall under its own weight. Sections of the stems are covered with mucus. Damage to tubers begins with the appearance of dark dots, which gradually turn into dark putrefactive spots. The skin of the potato is covered with cracks, from which a foul-smelling, sticky liquid flows. If the surface of the tuber remains clean, then the infection can be determined by the too light weight of the root crop.
You can defeat the black leg with the help of drugs "Maxim", "Prestige" and "TMTD". And in order to avoid infection, it is important to follow the basic rules for the care and storage of the crop. Crop rotation, quality planting material, disinfectiontools and weed removal is the key to a he althy plant.
In general, the fight against bacterial diseases is similar, regardless of the type of bacteria. In the following sections, we will share photos, descriptions and treatment of fungal potato tuber diseases.
Common scab
This disease is the result of vital activity of fungi of the genus Streptomyces. The reason for their occurrence is considered to be insufficient care, a high content of lime or sand in the soil, as well as too long hot weather. Infected fruits can be eaten, but their taste and appearance does not change for the better. The surface of the tubers is covered with asymmetrical brown sores, which gradually acquire a cork structure and merge into a single spot. When digging potatoes on fresh tubers, you can find a trace of mycelium, which disappears as it dries. The core of the tubers does not change its appearance at all, regardless of the degree of damage. The main measures to combat potato disease, the photo and description of which are presented in this section, are timely crop rotation and proper fertilizing.
PhD and professor of NUBiP of Ukraine Ivan Markov found that the use of fresh manure and excessive use of nitrogen-containing dressings contributes to the active development of this fungal disease. Therefore, nitrogen stabilizers, as well as manganese and ammonium sulfates, should be applied to the soil. Competent dosage of potassium preparations,calcium chloride and manganese can significantly reduce the harmfulness of scab. However, the amount of the above additives is determined only after a thorough laboratory examination of the soil sample. If this is not possible, then you can give preference to varieties that are resistant to this disease. For example, "Glow", "Vesta", "Symphony", "Lugovskaya" and others.
Powdery scab
The causative agent of powdery scab is the false fungus Spongospora subterranea. The people also call it a slime mold because of its appearance - an amoeboid lump is capable of movement due to plant cells and leads a parasitic lifestyle. Under adverse conditions, it is covered with a protective shell, being in which it can exist for about four years. When dampness occurs, the shell is covered with mucus, which greatly facilitates the process of moving the parasite. Affected roots and tubers become susceptible to the action of putrefactive bacteria and dangerous viruses. The infection of the plant begins from the root system, after which it passes to the stems, leading to their withering. On tubers, the disease appears as white galls and warty pustules. As the disease progresses, the sores crack and fill with powder. The embossed skin gives the sores a star-shaped shape. Especially active development of the disease occurs in a humid environment with a long absence of sunlight.
The fight against diseases and pests of potatoes consists in regular crop change and planting of high-quality material, previouslytreated with "Maxim". Root crops intended for subsequent planting are harvested only in dry and warm weather. If the soil is contaminated with powdery scab, it is permissible to plant potatoes in this area no earlier than after seven years.
Silver scab
This type of scab is caused by fungi of the genus Helminthosporium solani, which affect only the peel of the root crop. At the first stages of the development of the disease, it is rather difficult to detect infection, only with the development of the mycelium, brown spots appear on the skin of the tuber. The main danger of this disease is an increased risk of re-infection with other infections. When an affected tuber gets into a box with planting material, he althy tubers become infected, leading to the development of weakened bushes with thinned stems. You can recognize the appearance of the disease already when digging up the crop. Clearing the tuber from the ground, you can find small light brown spots. With the onset of spring, silver-colored dents form in place of the spots, formed in the process of peeling fabrics. With severe damage, the tuber shell loses moisture and deforms.
The development of the disease occurs at high humidity and high air temperature. At +15 ° C, pathogenic spores develop in an hour. But already at a temperature of +3 ° C, development stops abruptly. The main ways to protect potatoes are practically no different from those used in previous situations. The only exception are preparations for the treatment of seedmaterial - "Fundazol", "Nitrafen", "Titusim". Moreover, dressing is carried out immediately after harvesting, before being sent for storage.
Black Scab
Rhizoctoniosis, as this disease is also called, affects not only tubers, but also other parts of the plant. This is the main difference from other fungal diseases such as scab. Infection occurs due to poor-quality substrate, and its active development occurs in the winter season. Black scab harms not only potatoes, but also neighboring crops planted in cold soil. Young potato sprouts have a weakened and oppressed appearance. Root crops are covered with black exfoliating dots, similar to warts, which merge into single spots with a more severe lesion. Brown sores form on the stems of the plant, the root part is covered with white bloom, and the root system is covered with rough spots. Due to the massive spread of pores, you can lose the entire crop in a fairly short time.
Favorable conditions for the development of black scab are considered to be increased dampness and cold. Therefore, it is important not to rush into planting potatoes - wait until the earth warms up well and dries out. Planting material is carefully examined in order to reject defective tubers. Before planting, the tubers are treated with fungicidal preparations, and after harvesting, the tops are removed from the site. Fertilize the soil exclusively with rotted organic top dressing. An infected bush can be treated with strong chemicals, such as"Kolfugo", "Mankozeb" and "Fenoram super".
Alternariosis
Dry spotting is caused by fungi of the genus Alternaria, which actively develop in dry weather at high air temperatures. You can determine the infection already during flowering. Symptoms of the disease are clearly manifested throughout the vegetative period. Alternariosis affects leaves, stems, root system and tubers. Brownish spots appear on the leaves and stems, having a round or triangular shape. Due to the easy wind spread, a rather rapid infection of almost all cultivated plants on the site occurs. The main reason for this development of the disease are constant fluctuations in air and soil humidity, excess phosphorus content and lack of potash and nitrogen supplements.
Young tubers become infected with dry spot when they come into contact with the ground during the harvesting process, and more mature fruits - when the fungus gets on damage and abrasions. You can destroy the fungus by immediately destroying the source of infection using the method of autumn plowing. It is also important to plant potatoes as far away from tomatoes and other nightshade crops as possible. Having found the slightest signs of infection on young sprouts, immediately treat the plants with a fungicidal preparation. For better distribution of the fungicide, it is desirable to carry out the treatment in rainy weather. There are potato varieties resistant to this disease: "Lina", "Victory", "Volzhanka".
Cancerpotatoes
Fungal quarantine disease is caused by the active action of microbes. Affected potato tubers must not be transported from the site where they are grown. Harmful microorganisms infect the fruits and roots of the plant. Cancer can be recognized by growths on tubers, the appearance of which resembles cauliflower, which are clearly illustrated in the photo of potato disease. As the disease progresses, the growths increase in size and move to the stems, changing color. At the final stage of the disease, they acquire a black color and a slippery, rotten surface. The most rapid spread of spores occurs in moist soil conditions. The fungus enters the soil with untreated equipment, fresh manure and pests. The fight against potato disease is carried out by completely removing the plant along with the fruits. The source of infection is watered with kerosene or bleach and buried to a great depth. It also helps to burn an infected bush with mature tubers, since they are completely unsuitable for planting.
To protect plants from the mass spread of parasites, the site is treated with bleach, after which crops are planted on it. You can give preference to cancer-resistant crops, for example, these are Spark, Spark, Temp or Dawn.
Dry rot
Fusariosis, as this disease is scientifically called, develops with improper storage, gross violations of agricultural technology and mechanic altuber damage. Bushes of an infected plant wither and cease to be viable. On the cut of the diseased process, a dark ring can be seen. Symptoms of the disease also appear in the form of clearly visible brown spots on the tubers, which eventually become dents. The shriveled skin on the damaged areas gradually becomes covered with a white pubescent coating due to exposure to pathogenic fungi, as shown in the photo of the potato disease.
The fight against them involves the use of fungicidal preparations that process planting material. To protect plantings from the spread of the disease allows compliance with the rules of care and the prevention of mechanical damage.
Light blight
One of the most common and insidious potato diseases affects the entire plant, starting from the foliage during bud formation. They learn about the appearance of the disease by spots on the leaves, which have a felt structure and a brownish tint. Spots appear on the reverse side of the leaf, gradually growing over its entire area and becoming covered with a white coating. Affected stems have long brown stripes on their surface. A diseased plant is not able to develop due to the beginning processes of decay.
A potato disease develops, the description and photo of which is indicated above, with high humidity and lack of ventilation. Thus, the main preventive measure is the normalization of the irrigation regime and regular loosening of the soil. When the soil dries out, fungi slow down their development, however, this is notmeans complete victory over them. Affected bushes must be treated with garlic infusion or boric mixture.
Ordinary Mosaic
The development of potato disease, which is described in this section, is due to the simultaneous action of several viruses. Favorable conditions for the spread of this disease are mechanical damage and the presence of pests. As shown in the photo of potato disease, young leaves are covered with small light green dots that have an asymmetric shape. With the development of the disease, the color of the mottling changes to a darker one, and the disease spreads to the entire bush.
Wrinkled Mosaic
Infected plant leaves swell and form numerous folds. This disease occurs due to a disturbed outflow of waste products. Three years after infection, the potato bush becomes dwarfed, and its leaves take on a corrugated appearance. A diseased plant is not capable of developing buds and fruits. Its growing season will end much sooner than he althy plants.
Gothic
The development of this disease is due to the ingestion of the fusiform veroid virus into the tissues. The virus has a detrimental effect on tubers, changing their shape and taste. Potato leaves stretch and develop incorrectly, and the bush itself does not grow well. The edges of the leaves turn purple. Red-skinned varieties of potatoes gradually lose their color brightness. In addition, the fruits take the form of a spindle, as a result of which this disease is named"fusiform".
Necrosis
Tobacco rattle virus is responsible for the development of tuber necrosis, which reduces the starch content in the tuber. The characteristic symptoms of infestation are light speckling on leaves and dark spots on mature tubers, as shown in the potato disease photo. Unfortunately, this disease cannot be treated, as is the case with other viral infections. For prevention, it is only permissible to remove weeds and destroy insects that can spread the disease to he althy plants. In addition, the relationship of high humidity and high sand content in the soil with the active development of this disease was noted.
So, we talked about all the diseases of potato tubers. You could find photos and descriptions of the various states of this vegetable in this article.
