Methods for combating potato diseases. Diseases ring rot Is it possible to eat potatoes with ring rot

The main problem of all gardeners is plant diseases, which not only spoil their appearance, but also reduce yields. Potatoes are a very productive crop, but diseases and pests can reduce all work to zero.

Potato diseases: photo, description and methods of treatment

Potato diseases spread quite quickly as pathogens move from stems to tubers, causing crop loss. To prevent this, it is necessary not only to carry out pre-sowing treatment of planting material, but also to carefully monitor the vegetables in the growing process. When the first signs of disease are detected, they are treated with special means.

Causes

The main causes of pathologies include improper selection of planting material, crop rotation violations and improper plant care. Most modern hybrid varieties are disease resistant. However, when growing varieties that are not suitable for a particular climate, this property is lost. Therefore, it is recommended to grow local varieties adapted to climatic and soil conditions. Crop rotation also plays an important role. Pathogens often linger in the soil, and if the crop rotation is disturbed, they infect crops at the very beginning of cultivation or at the stage of tuber maturation.

Improper care can also lead to the development of diseases. For example, excessive watering can provoke late blight, and elevated temperatures can cause fungal diseases.

Symptoms

Most gardeners notice symptoms of potato diseases already at the harvest stage. However, with certain knowledge, signs of diseases can be seen earlier. So, late blight damages not only tubers, but also causes blackening of leaves and stems.

The presence of aphids will also help to establish that plants may be infected. These insects are carriers of many diseases, so it is important to remove weeds in time and spray against pests.

But the main sign of damage to crops is the general condition of the ground part of the plants. If they begin to turn yellow prematurely, wither or stun, it makes sense to inspect the root and tubers. This will help diagnose the pathology and choose a drug for spraying.

Kinds

There are several types of potato diseases. They differ in the type of pathogen that provokes the disease.

Allocate such types of potato diseases(picture 1):

Bacterial transmitted through tubers intended for planting or soil. The causative agents of diseases of this group can stay in the soil for a long time and do not die at low temperatures. Bacterial diseases include rot and black leg.
Viral provoke changes in the structure and color of leaves, stems and tops. As a result, the plant becomes weak and cannot form enough tubers. Viral diseases include different types of mosaics.
Mushroom diseases can damage all parts of plants: tubers, leaves and stems. The most famous example of fungal infections is late blight, which, if massively affected, can lead to the loss of most of the crop. The danger of fungal diseases is that they not only damage the tubers, but also make the culture vulnerable to other diseases.

Figure 1. The main types of potato diseases

Each type of disease requires specific treatment and prevention. Therefore, before starting field work, it is recommended to treat tubers with special preparations.

From the video you will learn all about common potato diseases and how to deal with them.

Peculiarities

The main feature of potato diseases is that they damage mainly tubers. As a result, not only the crop intended for human consumption is lost, but also the quality of the seed is deteriorating.

In addition, the features of potato diseases can be considered their latent course. Most pathologies are almost impossible to diagnose with an external examination, and symptoms begin to appear only at harvest or mass damage (when plants are significantly stunted). That is why the pre-sowing treatment of tubers plays an important role.

Bacterial potato diseases (causes, symptoms and treatment)

Infection with bacteria occurs directly from the soil in which pathogens are located. However, the spread of diseases can also occur directly through the tubers if they are not inspected and treated before planting.

The danger of bacterial diseases of potatoes is that they damage the stems and lead to the death of the crop. Most often, pathogens affect tubers. They begin to rot and become unfit for food.

Ring rot: photo, description and treatment

Potato ring rot is dangerous because it causes serious damage to the crop and spreads quickly.

Note: With a mass defeat by ring rot, yield losses can reach 45%.

The disease affects stems, leaves and tubers. Their vessels are damaged and the sprouts gradually die. If you cut the stem and press on it, a yellow mucous liquid will begin to stand out (Figure 2).

Figure 2. Signs of ring rot

Tuber ring rot is of two types. Pitted provokes the formation of yellow oily spots directly under the peel. With the ring type, necrosis of the vascular ring begins, it first becomes yellow, and then brown.

Brown bacterial rot

The disease affects only tubers. Bacterial brown rot of potatoes intended for planting can cause stunted plant growth and delayed development. With a strong defeat, the seedlings wither even at an early stage of cultivation.

Note: Bacterial brown rot is difficult to identify, as its symptoms begin to manifest clearly only in the second year.

Figure 3. Symptoms of brown bacterial rot of potato tubers

You can notice the signs of the disease even at the flowering stage (Figure 3). Affected plants wither, leaves turn yellow and begin to wrinkle. In order to prevent crop loss, crop rotation must be strictly observed and planting material carefully selected. In addition, it is recommended to select varieties that are resistant to bacterial brown rot.

Mixed internal rot

Mixed internal rot appears on tubers with mechanical damage. Fungi and bacteria penetrate inside, and the vegetable begins to rot from the inside.

Very often, the disease does not appear during cultivation, but during storage. In order to prevent crop loss, the storage is treated with copper sulphate and thoroughly cleaned of plant residues. Tubers should be inspected before storage.

wet rot

Wet rot on potatoes appears with excessive watering and high soil density. This causes massive rotting of tubers right in the soil (Figure 4).

The disease can also manifest itself during storage. If the room is too humid and the temperature is above 5 degrees, wet rot can destroy almost the entire crop. At the same time, the tubers rot from the inside, outwardly remaining absolutely normal.

Figure 4. Wet rot on potatoes

For prevention, planting material must be carefully selected, and if wet rot is found, destroy all tubers from the bush and those located nearby. In addition, it is necessary to strictly observe the storage technology, preventing an increase in humidity and temperature in the room.

Blackleg

This is a bacterial disease that often occurs when potatoes are planted in an area where cabbage was previously grown. When affected, the lower part of the stems begins to rot, and the tubers become wet (Figure 5). As a result, the quality and quantity of the crop decreases, including during storage.

Note: The black leg is very dangerous, since in case of mass damage it can cause the death of 60-70% of the crop.

Figure 5. Signs of a black leg on the stems and tubers of potatoes

In the early stages of development, the black leg provokes yellowing and wilting of the lower leaves. The stem becomes thin and easily pulled out of the soil. The tubers become soft, begin to rot and gradually acquire an unpleasant odor. To prevent disease, you need to carefully check the planting material and remove all plant debris after harvesting. In addition, it is necessary to carefully observe crop rotation, pickle tubers before planting, and choose disease-resistant varieties.

Virus diseases of potatoes

Viral diseases include a mosaic of different types. The disease got its name from the characteristic changes in the color and structure of leaves, stems and bushes in general.

Viral mosaic vulgaris

An ordinary viral mosaic in the early stages is manifested by the appearance of yellow spots of various shapes and sizes on the leaves. The same symptoms are characteristic of iron deficiency, therefore, to clarify the diagnosis, you need to carefully monitor the bush.

If, after yellowing, the spots turn brown or brown, then the plant was infected with a viral mosaic. The bush must be dug up and burned. In addition, it is necessary to carefully examine neighboring plants and carry out preventive spraying with antiviral drugs.

striped mosaic

A common viral disease with many strains. Symptoms of striated mosaic differ depending on the type of pathogen, but in general, this disease also has common characteristic symptoms (Figure 6):

The stems become brittle and break easily;
Pronounced spots and stripes appear on leaves and stems;
The veins on the lower parts of the leaves are covered with dark brown spots.

Figure 6. Symptoms of striated mosaic

The striped mosaic spreads rapidly, so when the first signs are found, the plant must be destroyed.

wrinkled mosaic

A wrinkled mosaic can cause serious crop damage. However, the disease appears only in certain years and in the presence of suitable climatic conditions. The virus develops especially actively in hot dry years.

Figure 7. Potato bushes affected by wrinkled mosaic

Plants affected by wrinkled mosaic are severely stunted and do not bloom (Figure 7). Reducing the growing season leads to a loss of yield (with a massive defeat, the shortage can reach 30%).

A characteristic symptom of the disease is leaf curl. They brighten, wrinkle and gradually die off. In this case, the leaves remain on the bush, but the plant itself completely stops growing and does not bear fruit.

fungal diseases

Fungi that cause damage to tubers and bushes spread quickly and penetrate the plant through mechanical damage. This process can additionally cause bacterial or viral damage.

There are many fungal diseases, therefore, in order to correctly determine the disease and fight it, you need to know exactly what this or that disease looks like.

late blight

Potato late blight is the most dangerous disease of this crop. If it is not determined in time and appropriate measures are not taken, crop losses can reach 70%. Late blight destroys not only tubers, but also affects stems and leaves, slowing down plant growth.

Figure 8. Symptoms of late blight on potatoes

The main symptom of late blight is brown spots on the leaves, which appear mainly during the flowering period (Figure 8). At high humidity, they become covered with a characteristic white coating.

Further development of late blight provokes damage to tubers. Hard spots of dark gray color appear on their surface. The causative agent of the disease remains in the tubers and soil, therefore, before planting, it is imperative to treat the tubers, and in the process of growing, carry out preventive spraying.

black scab

A viral disease affects all parts of the plant, and if infection occurs in the early stages, all young shoots may die.

Figure 9. Black scab on potato tubers

Black scab of potatoes is dangerous not only during cultivation, but also during storage of the crop. Mature tubers become covered with brown spots and gradually rot (Figure 9). The development of the disease is promoted by high temperature and humidity. The pathogen remains viable on tubers and in the soil.

Prevention of black scab includes observing crop rotation and planting disease-resistant varieties. In addition, tubers can be sprayed before planting, using Maxim, Fenofram Super or Kolfugo for this.

silver scab

It is very easy to identify silver scab potatoes. To do this, just hold the tuber in your hand. The lungs of potatoes are infected as the disease causes moisture loss. Such vegetables are not suitable for planting or eating (Figure 10).

Figure 10. Signs of silver scab on potatoes

Silver scab appears on planting material closer to spring. The peel of the potato acquires a characteristic silvery sheen and is slightly pressed inwards.

Note: Silver scab will actively develop if the potatoes are stored in a room with a humidity of more than 90% and at a temperature above +3 degrees.

To prevent infection, all tubers must be dried after harvest. In the storage, you need to maintain a stable temperature and humidity, and observe crop rotation when planting. You can also carry out pre-sowing treatment of tubers with fungicides.

powdery scab

The disease actively develops in rainy years. Powdery scab symptoms appear on the lower parts of the stems, roots and tubers (Figure 11).

Note: If you send potatoes infected with powdery scab for storage, you can lose part of the crop. This is due to the fact that rot can penetrate through the sores formed on the tubers.

Figure 11. Signs of powdery scab

In the process of growing, powdery scab can be identified by the characteristic white growths on the roots and stems. Later they darken and collapse, forming red ulcers on the surface. The causative agent of the disease remains viable not only in tubers, but also in soil and manure.

When potato cancer is detected on the farm, quarantine is announced, as this disease is considered one of the most dangerous. The main symptom of cancer is the formation of tubercles on tubers. Gradually, they increase in size, and their surface becomes uneven and rough (Figure 12).

Figure 12. Signs of potato cancer

When a disease is detected, the affected plants are destroyed, and the remaining bushes are sprayed with special preparations. After that, potatoes cannot be grown in the ground for another 3-4 years.

Dry rot

Dry rot of potatoes is also called Fusarium wilt. They can affect plants at all stages of development, but most often the culture is vulnerable during the flowering period.

Note: In hot weather, dry rot develops especially actively. In this case, yield losses can reach 40%.

A symptom of Fusarium wilt is a change in the color of the upper leaves (Figure 13). They brighten, gradually begin to fade. Brown spots appear at the bottom of the stem, and if the weather is wet, these areas become covered with bloom and begin to rot.

Figure 13. Symptoms of dry rot

You can determine dry rot by cutting the stem. It has clearly visible brown vessels. Affected plants must be removed from the soil and burned, as the disease can quickly spread to neighboring bushes.

Methods for dealing with dry rot include regular inspection of plantings. It is also necessary to comply with crop rotation standards, select only high-quality planting material and process it before planting in the ground.

Prevention of potato diseases

Most potato diseases can significantly reduce yields. To prevent this, you need to follow certain preventive measures:

Choose varieties of potatoes that are resistant to diseases and pests. It is better to give preference to local varieties that are best adapted to the climatic and soil conditions of a particular region.
Carry out pre-sowing treatment of tubers with special preparations. They strengthen planting material and significantly reduce the risk of infection of tubers by bacteria and viruses.
Observe crop rotation - without this condition, tubers can be affected by diseases of other crops, which are also dangerous for potatoes.

Figure 14. Preparations for the treatment of potato tubers before planting

After harvesting, be sure to remove all tops and plant debris. In addition, during the growing process, weeds should be regularly removed, and when the first signs of diseases are detected, preventive spraying should be carried out.

How to process potatoes before planting from diseases

There are many preparations intended for the treatment of tubers and adult plants against diseases. The most common means include a solution of copper sulfate (concentration: a teaspoon of the product per 3 liters of water). In this case, the tubers are not sprayed, but immersed in liquid for about two minutes, then dried and planted in the ground. Examples of culture preparations are shown in Figure 14.

To protect against fungal diseases, the drug Fitosporin-M is used. The working solution is prepared according to the instructions on the package, and the tubers are dipped into the liquid for 15 minutes, after which they are dried and planted.

Maxim, Prestige, Quadris and Konfugo are considered effective remedies against diseases.

The author of the video will talk about the pre-sowing treatment of tubers to protect the potato crop from diseases.

Some gardeners, in order to avoid crop losses from potatoes, are planted using innovative technologies in barrels, bags and under hay. But soon they are convinced that this does not save the tubers from bacteria, fungi and viruses that provoke a variety of ailments. They mercilessly infect healthy plants and their fruits in the open field, and even in the cellar. Others often act as carriers of pathogens. Let us consider in more detail what potato diseases are, and measures to combat them.

Important! It is almost impossible to instantly cure planted tubers from diseases of any nature. This is due to the fact that most pathogens infect the soil or seed. As a result, the fight against them should begin with the processing and treatment of fruits, as well as the thorough preparation of the beds for planting.

Bacterial diseases of potatoes

Bacterial potato diseases are provoked by various kinds of microbes, which gradually spread from the tubers along the stems, infecting everything. It is extremely difficult to deal with them, since the soil in which the root crop grows also needs disinfection.

To cope with such a task, timely and competent sevosmena is needed. Sometimes this will take years with alternate sowing of microorganism-resistant crops on the infected area, such as: wheat, corn, barley,.

Brown bacterial rot

The disease occurs due to the vital activity of microorganisms Ralstonia solanacearum on potatoes. Its first manifestations are noticeable during the flowering period of the culture, when root crops begin to form. At this time, yellowing and wilting of the foliage is observed, it becomes wrinkled and lifeless, and the stems fall down and turn brown over time.

To the extent of reproduction of pathogenic bacteria, softening and putrefactive processes are noted in the lower basal part of the stem. Splits are clearly visible along the sprouts, and the infected veins acquire a brown putrefactive color.

If the stem of a diseased plant is cut, dark brown fibers can be seen on the cut ring. When squeezing such a sprout, a gray-white muddy mucus will stand out from it.

Botanists classify brown rot as a vascular disease of potatoes and note the death of bushes as a result of clogging of the xylem veins with a dense gum mass. There are cases when the disease is manifested only by verticillium wilt and ring rot, in which there are no splitting of the shoots and mucous discharges are observed.

The disease on tubers is expressed by a softened vascular ring and the appearance of brown putrefactive elements on the core. Often, decay processes begin already in storage. They are accompanied by mucous secretions and an unpleasant odor. Such potatoes infect all neighboring tubers and completely rot.

Did you know? According to the International Finance Corporation, Ukrainians annually consume about 4 million tons of potatoes, while the average annual yield of root crops is approximately 18-19 million tons.

Leading agronomists of the country draw the attention of farmers and landowners to the fact that the fight against bacterial diseases of potatoes should be aimed at comprehensive protection against the pathogens described above. At the heart of all such measures is the management of relations between the internal and external population.

This means that the plant must be protected throughout the entire growing period by various methods, including seed production and organizational and economic nuances, as well as the principles of crop combination.

When brown rot appears, crop rotation and the application of optimal fertilizers are of key importance in the fight against it. It will be possible to plant potatoes on an infected one only after 5 years. Seed tubers need to be carefully sorted out and be sure to warm up for 20 to 30 days. This will help to accurately detect unsuitable material. It will also be indicated by a 0.002% solution of succinic acid, with which the fruits are treated for half an hour.

If during planting it becomes necessary to cut the root crops, the knife must be disinfected without fail with formalin or potassium permanganate. Healthy, for prophylactic purposes, before planting, they are treated with chemicals such as: "TMTD", "Rizoplan", "Bactofit", "Polycarbocin", repeating the treatment twice on seedlings until budding begins.

Varieties with increased resistance to microbes are well cultivated: "Resource", "Ulyanovsky", "Luck", "". The fight against bacterial diseases of potatoes includes regular inspection and removal of diseased plants.

Experts advise the first cleaning to be carried out after the stems reach 25 cm in height, the second - during flowering, and the third - a few weeks before harvest. It is important during this period to completely mow the tops so that they have time to dry before harvesting the fruits. The entire crop should be well dried before laying in the cellar. Preparatory work is also needed in the storage.

To this end, they remove all the remaining last year's and, carry out disinfection with a 2% aqueous solution and treat the walls with slaked. At the entrance to the room, a rug soaked in a 5% solution of copper sulphate is placed.

Important! For the safe preservation of potato tubers in the cellar, the first 20 days the temperature in the room should not be lower than +13 ° C, and the air humidity should be kept at 90%. In the future, gradual cooling to 2 degrees is necessary.

ring rot

Signs of ring rot are quite noticeable on tubers and potato biomass. They appear after flowering in the form of yellowing of thin shoots and twisting of the leaves. Affected specimens are difficult to pull out, even with general cell death. This happens due to the destruction of the sinewy structure of root crops and shoots.

The disease begins from the roots, but its first symptoms can be noticed on the fruits only when they are cut. Yellow or brown rings at the edges of the core indicate the further development of putrefactive processes that will eventually destroy the entire fruit. When pressed, gray-yellow mucus flows from the affected areas.

If, when examining the seeds, you did not notice signs of rot and planted such a root crop, dwarf, poorly developed, thin shoots with small deformed leaves will grow out of it. Do not expect a big harvest from such bushes.

In most cases, bacterial diseases occur due to poor-quality planting material, or due to mechanical damage during harvesting of root crops, transportation of tubers in contaminated containers, as well as violation of storage rules. To date, there are no special pesticides for putrefactive diseases of nightshade crops.

They are fought with quarantine methods, which, in addition to competent preparation of planting material and harvesting, include a sevosmenu for 3 years, the selection of resistant varieties, potato fields with potash preparations and the systematic removal of diseased plants at the first sign of rot.

Did you know? Potato diseases destroy from 30 to 65% of the crop.

wet rot

The disease begins from the core of the tubers and is often difficult to determine at the initial stages of development. Its root cause is bacteria or fungal pathogens that enter the root crop during mechanical damage or are carried by pests. Based on these factors, it becomes clear why potatoes quickly rot from the inside.

This process is expressed in the softening of the tubers and the spread of a strong stench. Rotten fabrics are initially white, and later they turn brown, gaining dark shades. By the way, the skin is affected when the inside completely rots. It happens that the surface of the root crops is covered with dark dents, from which, when squeezed, a whitish starch substance flows out.

If the root crop gets into cold conditions, its eyelids die off, and the process of decay begins. Therefore, such tubers should not be protected, it is better to use them immediately, otherwise they will ruin the entire crop. Farmers note that very often potatoes are affected by this disease in the cellar, especially when the product freezes or, on the contrary, is piled into the compartment and stored at temperatures above + 4 ° C.

The appearance is also accompanied by high humidity in the room and poor ventilation. This is due to a lack of oxygen, which entails a decrease in the immunity of potato fruits. You can get rid of the problem, again, with complex measures. To do this, it is important to ensure that the soil in which the culture grows is not waterlogged and is well loosened. When laying in storage, select healthy tubers and dry them thoroughly.

It is advisable to treat seed potatoes before bringing them into the cellar with the Maxim chemical preparation. And also protect the crop from all sorts of abrasions and cuts, take pest control measures in time. For the winter, put root crops, regardless of their purpose, in boxes or vegetable nets. In cases where you find putrefactive foci, remove all tubers from the infected area and try to use them as soon as possible. Also, strictly follow the rules for storing potatoes (we mentioned them above).

Did you know? Every year, Europeans harvest about 35 tons of potatoes from 1 hectare, while Ukrainians only 15 tons. This difference arises as a result of the fact that 95% of the product is cultivated in small farms, which, of course, is reflected in the quality of the tubers.

Mixed internal rot

This disease of potato tubers, like the previous types of bacterioses, occurs when root crops are not wintered properly and due to mechanical abrasions, bumps, and cuts. Symptoms depend on the type of pathogens that have entered the tissue membranes of the tubers. You can observe the signs of wet or ring rot, as well as dry rot, that we have already described. On the affected areas, a gray, pink or brown slippery coating will necessarily appear.

The methods of dealing with these microbes are no different from those mentioned above. Your main task is to protect the crop from mechanical damage, to provide the right conditions for its conservation. Seed material is important to disinfect before planting with any antibacterial and antifungal chemicals. Experienced summer residents advise the preparations "Fludioxonil" and "Maxim".

Blackleg

The disease begins to manifest itself as soon as favorable conditions come: increased dampness or prolonged hot weather. During drought, the course of the disease is sluggish and becomes chronic. The black leg is noticeable both on the underground and aboveground parts of the potato: the stem turns black below, the leaves turn yellow, the bush gradually fades, and the roots begin to rot.

In the heat, after a week, softening of the sprouts will begin in the root zone, which usually fall due to their own weight. Infected specimens are easily pulled out, mucous secretions are visible on sections of the stem. Tubers rot from stolon areas, covered with dark dots. A sure sign of the disease are putrefactive spots on potatoes, darkened skin, cracks, from which a smelly pulling liquid is released. Such root crops are very light, which indicates the complete destruction of their insides by bacteria.

It is possible to overcome the black leg by strictly observing the rules of agricultural technology for growing potatoes, harvesting and storing them. In this aspect, crop rotation, planting high-quality seeds, timely loosening of the soil, phyto-cleaning and elimination of weeds, and disinfection of working equipment are important. It is desirable to pickle tubers before planting with preparations such as: "Maxim", "Prestige", "TMTD".

Important! In order for seed potatoes to be well preserved until spring, they need to be planted in autumn.

Fungal diseases of potatoes

Botanists describe this group of potato diseases as the most serious and dangerous. The appearance of various fungi on the bushes or in the roots of potatoes necessarily entails diseases.

They are often carried by harmful insects or provoked by improper conditions for the cultivation of root crops. Consider the brief characteristics of the most common fungal diseases and methods of dealing with them.

common scab

The disease appears as a result of the vital activity of radiant fungi of the genus Streptomyces. The forerunners of their occurrence are low level, limestone, sandy, sandy loamy substrates and hot weather conditions. The pathogen enters the tubers through the evergreen. Infected fruits lose their taste and presentation. Small brown asymmetrical spots appear on the potatoes, which eventually "cork".

To the extent of development, the sores merge together, and on freshly dug fruits, a plaque is barely noticeable. In the sun, it quickly dries up and loses its mark. The core of such root crops, despite the formed ulcerative crust on the outside, does not change. For preventive and curative measures, candidate of biological sciences, professor of NUBiP of Ukraine Ivan Markov advises to observe crop rotation and rules for feeding potatoes.

According to the scientist, fresh, overdose and contribute to the development of pathogens. Therefore, it is important to apply physiologically acidic substances with the calculation of 60 kg per 1 ha, which are manganese sulfate and ammonium sulfate. Nitrogen stabilizers are also desirable.

The harmfulness of scab is significantly reduced with proper dosage, calcium chloride, manganese, boron, copper, cobalt. You can calculate the required amount of listed chemicals for a particular field based on its agrochemical survey, which can only be done by a specialist.

If there is no opportunity and funds for laboratory tests, you can use the cheapest way to deal with scab, focusing on disease-resistant potato varieties. Do not be afraid of fungal diseases "Bozhedar", "Kosen 95", "Chernigovskaya 98", "Lugovskaya", "Borodyanskaya Rose", "Vesta", "Symphony", "Vodogray", "Veloks", "Gatchinskaya", "Volovetskaya ”, “Zarevo”, “Lybid”, “Drevlyanka”, “Serpanok”, “Poran”, “Rozara” and other varieties with thin skin of reddish tones.

Also, each land owner should take care of the condition. To enrich it with useful elements, it makes sense to organize a plow of green manure: lupine, clover or. High-quality root crops selected for planting are treated with Maxim, "" preparations and Agat-25K growth regulator before instillation. After the buds begin to form on the seedlings, the soil must be irrigated for 4 weeks, maintaining the humidity at 75%.

powdery scab

You can save potatoes from slime mold by regular seed shifts, planting high-quality seeds, which should first be treated with fungicides ("Maxim"). The collection of root crops should be organized in dry, warm weather, observing the above rules for harvesting and storing tubers. In heavily infested areas, re-cultivation of the plant is possible only after 7 years.

Did you know? According to the Main State Inspectorate for Plant Protection of Ukraine, in 1996 scab affected all plantings of potatoes in household plots and agricultural enterprises in the Lviv region. It was a burst of intensive development of mushrooms. The latest data of infection of tubers is 17 - 24%.

silver scab

By spring, they will show clear dents and a silvery sheen, which occurs as a result of complex processes of tissue exfoliation and access of oxygen to the formed cavities. In cases where mass infection occurs, the upper shells of the fruit are severely deformed, losing moisture.

Comfortable conditions for the development of silver scab on potatoes are dampness in storage and too high a temperature. For example, 1 hour at +15 °C is enough for the formation of pathogenic spores. At +3 °C, mushrooms are not produced.

Methods of dealing with silver scab are traditional, as in previous cases of bacterial and fungal diseases. They differ only in the means for disinfecting seed potatoes. Agronomists advise using drugs: "Vivatak 200", "", "Maxim", "Bontan", "Titusim", "Nitrafen", "Tekto 45". Dressing should be carried out immediately after harvesting the root crops.

Black scab (rhizoctoniosis)

Compared with silver and common scab, rhizoctoniosis affects not only tubers, but the entire plant. A disease appears from substrates infected with pathogens, especially in the cold season. In this way, black scab differs from other species and poses a great threat to tubers planted in unheated ground.

Young sprouts of diseased crops are very sparse and depressed. Black warty dots are noticeable on root crops, which easily peel off and can merge together.

On the stems, the disease manifests itself as brown sores, which in the basal part are covered with a whitish felt coating, and on the roots - with rough spotting. The mass spread of fungal spores can significantly reduce the yield and completely destroy it in the cellar.

Its development is promoted by cold and dampness. Therefore, for prevention, do not rush to plant potatoes, allow the soil to warm up and lose excess moisture. Inspect the seed roots well, discarding infected samples.

Before planting, it is important to treat healthy tubers with "Fundazol", "Prestige" or "Maxim". The timely alternation of crops in the garden, the elimination of tops before harvesting and plant residues after it, and the fertilization of the soil with exclusively rotted organic matter are also important.

Important! To increase yields, potatoes should be renewed every 4 years, giving preference to elite, non-infected varieties of Dutch selection.

It is also important to germinate seed tubers in the sun, since sprouts that appear in the dark are affected by black scab in the first place. Agrochemists advise treating diseased bushes with potent drugs: Ditan M-45, Kolfugo, Mankozeb, Fenoram Super.

Important! To save healthy potatoes from the misfortune of black scab, it is recommended to organize an early harvest of fruits.

Alternariosis (dry spotting)

Alternariosis of potatoes caused by fungi of the genus Alternaria, which are activated in dry and hot weather. You can notice traces of their vital activity starting from the flowering period of the plant. Symptoms are pronounced until the very harvest of root crops. The disease manifests itself on leaves, sprouts, rarely fungi infect tubers. You should be alerted by brown spots of a round or triangular shape that appear on the foliage or stems.

Mushrooms are easily carried by the wind, while infecting new areas of the garden. This is the danger of Alternaria disease of potato leaves. The fact of focal spraying of spores becomes clear. Their formation is facilitated by frequent changes in wet and dry weather, lack of moisture, unfavorable soil conditions, lack of potassium and nitrogen, and an excess of phosphorus.

Young fruits become infected with a fungus, in contact with the ground when excavated, and mature fruits - in the presence of abrasions and other mechanical damage. To destroy the fungi that provoke dry spotting, the first step is to eliminate the primary sources in the soil. This is done by autumn autumn plowing. Beds with potatoes in the future should be placed as far as possible from tomatoes, since alternariosis is dangerous for all nightshades.

Seed tubers should be carefully inspected, discarding specimens with a black or brown surface and slightly concave spots with uneven but clear edges. It is important to fertilize grown seedlings on time. As soon as you notice the first signs of the disease, immediately spray the planting with any fungicide. It is advisable to re-treat depending on the degree of infection and the long-term effect of the drug used.

Disinfection is best done in cool and damp, rainy weather. The percentage of harvest you save depends on following the rules of harvesting and saving it in the cellar. How to do it correctly, we have already mentioned above.

Some summer residents share their experience in planting varieties resistant to Alternaria. For example: Lina, Nevskaya, Pobeda, Skazka, Reserve, Lyubava, Skoroplodnaya, Volzhanka, Master.

Did you know? Spanish farmers flatly refused to cultivate potatoes only because root crops frightened superstitions with their human-like forms.

potato cancer

This is a fungal quarantine disease provoked by microbes, due to the activity of which damaged tubers are prohibited from being transported from their places of growth. Pathogenic microorganisms spread to the root crops and the root system of the plant. Cancer is manifested by growths with a wavy structure, which is similar to cauliflower.

Over time, these formations increase, change color, move to the root zone of the stems and stolons. At the final stage of development, they turn black with a slippery putrefactive surface. Spores are easily transferred to healthy fruits, especially during high soil moisture. They fall into the ground with the help of working equipment, animals and manure, remain viable for 4 years.

To get rid of the problem, pour infected fruits and tops with kerosene, bleach or formalin and bury to a depth of at least 1 meter. As an alternative, some gardeners suggest burning all affected plants, although surviving potatoes are not suitable for seed, as they are a potential carrier of pathogens. Such tubers are best used for food purposes.

Of course, the purchase of seed material is carried out exclusively in specialized centers. Before planting, inspect the tubers - cancer spores can hide under the ground adhering to their surface. Contribute to the release of soil from infectious microbes organic and mineral top dressing. But at the same time, it is important to ensure that the manure is well rotted. Chemical treatments for cancer are only available under the control of the Plant Quarantine Inspectorate.

Important!Before sowing, it is possible to disinfect tubers that have grown in cancer-affected areas using a 1% suspension of Fundazol.

Dry rot (fusarium)

The reasons for the appearance of dry rot on potatoes are gross errors in agricultural technology and unfavorable soils, as well as mechanical damage and improper storage of tubers in winter. The symptomatology of the disease clearly appears on the tubers in the form of dark marsh-brown spots, which eventually transform into shallow dents. The skin on the affected areas is wrinkled, pubescent plaque is noticeable. A similar picture is inside the fetus.

The bushes of the plant with the development of fusarium begin to fade, lower the stems and lose their viability. If you cut off a diseased sprout, you can see a dark ring at the place where the blade passes.

In order to destroy pathogenic dry rot fungi, it is recommended to strictly observe the rules of agricultural technology and storage of the harvested crop, plant only high-quality material, protect potatoes from bumps and cuts during harvesting, and annually carry out pre-sowing dressing of tubers with fungicidal preparations (for example, "Maxim", "Prestige").

late blight

Such a fungal disease of potatoes as late blight is considered the most insidious of the entire list of ailments. It affects the entire plant, but manifests itself, first of all, on the foliage during the budding of the bushes. You can learn about the appearance of late blight by brown felt spots that form on the underside of the leaves and, growing, cover the plant with a solid brown carpet with a slight white bloom. On the stems, the disease is given out by long stripes of a dark color. Such a plant is not able to fully develop, the processes of decay begin in it.

Favorable conditions for the occurrence of late blight are high humidity after prolonged rains, warm weather and lack of good ventilation. When the weather recovers and the soil dries out, the mushrooms stop their functioning. But this does not yet mean your victory over the disease, since after the first rain the disease will begin to progress.

In order to cure the culture, in addition to traditional methods, proper cultivation and storage of root crops, it is imperative that at the initial signs of late blight, organize spraying of the bushes with a boron mixture, "Oxyhom" or "Polyhom". Some summer residents resort to folk technologies for prevention, treating the leaves with garlic tincture six times. Begin this process at the beginning of flowering and repeat every 14 days.

Seed preparation is also important. In addition to germinating and rejecting everything unsuitable, the tubers should be treated with Fitosporin, boric acid or copper sulphate. The soil in the infected areas in spring and autumn is also etched with the above preparations.

Did you know? In the 17th century, the French introduced a fashion for decorating costumes and wigs with bouquets of potato flowers. In this country, the plant has long been cultivated as an ornamental.

Potato phomosis

The causative agents of phomosis penetrate into the root crops, stems and walls of potatoes, having a detrimental effect on them. The sore appears as elongated shapeless spots covered with brown dots.

To the extent of development, fungal spores ring the shoots and prevent the culture from developing. Affected bushes differ from healthy ones in the loss of foliage color saturation and lifelessness. If no action is taken, the plant will die. On tubers, signs of phomosis are expressed in the form of sores that blur up to 6 cm. Over time, deep cavities appear in the affected areas. Similar specimens stored in the cellar contribute to the reproduction of mycelium. They are also accompanied by post-harvest residues and weeds abandoned in the garden.

Virus diseases of potatoes

Dangerous causative agents of potato viral diseases cause damage to yields gradually, resembling a time bomb. In the first years, their vital activity is almost imperceptible, but in the future they destroy up to 50% of the fruits. Carriers of such diseases are Colorado beetles, aphids, cicadas and other pests. And also infection during the processing of root crops is not excluded. Let us dwell on the most common potato ailments caused by viruses.

ordinary mosaic

It is provoked simultaneously by several viruses. For this, mechanical processing and the presence of harmful insects in the garden are favorable conditions. It appears on young leaves as barely noticeable light green dots of an asymmetric shape. Over time, such mottling darkens and spreads to the entire bush.

wrinkled mosaic

When infected, the tissues of the leaves of the plant swell strongly, forming peculiar folds. They arise as a result of a poor outflow of assimilated products. 3 years after the cultivation of infected potatoes, you will notice how the plants degenerate into dwarf ones with corrugated underdeveloped foliage and very fragile stems. Such a bush is not able to tie buds and bear fruit. He will finish his one month earlier than healthy specimens.

striped mosaic

For striped, the characteristic features are mosaic speck, which, first of all, appears on the lower and middle leaf plates. Later, black stripes form on the affected areas and on the veins. The leaves break easily, die off quickly, often hang lifelessly, exposing the stem before budding. The pathogen overwinters in root crops.

Gothic potato tubers

The disease occurs through the ingestion of the vertiform veroid virus (VVKV), in connection with which it is also called "vertiform". A harmful microbe is manifested by the deformation of tubers, the deterioration of their taste and presentation. The foliage of diseased bushes is too elongated, very small, and develops incorrectly. On the edges of such leaves have an anthocyanin hue. Diseased plants grow poorly, lag behind in growth, and the color is lost on the tubers of red-skinned varieties. At the same time, root crops grow small in size with a spindle-shaped shape.

Did you know? The most dangerous and widespread viruses are PLPV and PVY, which reduce the mass, number and starchyness of tubers, killing up to 80% of the crop.

Potato tuber necrosis

The development of necrosis on potatoes begins with the penetration of the Tobacco rattle virus into the soil and on the tubers, which reduces the starch content and leads to fruit necrosis. The characteristic features of the disease are small light spots that cover the leaves, deformation of the inflorescences, dark necrotic spots on the root crops, which often bend into bizarre stripes, arcs or rings.

A very high prevalence of this virus is noted in sandy and swampy areas. To date, there is no drug for viral diseases of potatoes that would immediately solve the problem. However, in order not to lose the entire crop, if symptoms of any of the listed viral infections are detected, immediately arrange a phytocleaning, periodically repeating it until all the affected plants are removed.

Was this article helpful?

Thank you for your opinion!

Write in the comments what questions you did not receive an answer to, we will definitely respond!

You can recommend the article to your friends!

Kira Stoletova

It is not easy to keep the potato crop grown on your personal plot until spring, even if you take all measures to ensure long-term storage. In a number of reasons why stored vegetables begin to deteriorate, potato rot occupies the first place.

Dry rot

The most common fungal disease of vegetable crops in the regions in the south and southeast, as well as in the Russian Far East, is Fusarium dry rot of potatoes. The danger of dry rot is that it can damage up to 40% of the entire potato crop. The second name for this fungal disease is Fusarium brown potato rot.

The causative agent of dry Fusarium disease of vegetables, which causes rotting of root crops, is a fungus that damages root crops and the root system of the plant, spreading through contaminated soil through the remains of vegetation and with infected potato tubers.

signs

The primary signs of brown bacterial rot of potatoes can be detected at the flowering stage of the plant:

the upper tier of the leaves of the potato bush begins to lighten, and subsequently fades,
the lower tier of foliage becomes brown, in conditions of high humidity it can acquire a bloom with a pink or orange tint,
in the context of the stem, vascular rings are observed,
tubers affected by dry fusarium disease become dull, with a gray and brown tint, slightly depressed foci-spots, under which the potato pulp dries out, and the peel on top wrinkles.

The result of infection of potatoes with dry fusarium disease is the complete drying of the plant: diseased tubers germinate poorly in the form of thin filamentous sprouts.

wet rot

The causative agents of wet bacterial potato rot are saprophytic bacteria that affect root crops weakened by pests and other diseases.

The disease manifests itself exclusively during the period of storage of the crop, when the temperature regimes are exceeded and ventilation conditions are not observed.

A contributing factor for the development of the disease on potato tubers is the cultivation of vegetables on waterlogged soil.

signs

The main symptoms of damage to potato tubers are:

decomposition of tissues of affected potato tubers and their subsequent development into a mucous mass,
a specific putrefactive pungent odor from infected tubers.

When planting overwintered infected potatoes, wet rotting during growth during the initial stages after planting can be expected. The provoking factor is the cold soil. The presence of planting material affected by rot becomes a source of infection for weakened tubers (damaged and frozen), and then spreads to healthy ones.

ring rot

The defeat of potato tubers by ring rot occurs at the stage of formation of root crops, in the process of damage to vegetables during mechanical harvesting methods and by direct contact of the harvested potato tubers with the disease-infected tops. Ring rot is caused by an aerobic bacterium.

signs

Pathogens begin to fill the vascular rings of vegetable tubers at the end of the winter period and the beginning of spring, and this causes rotting, the signs of which include:

the development of a rotting potato tuber into a white viscous mass,
bad smell from vegetables
voids inside the potato pulp.

Until the moment the tubers are cut, it is possible to guess about the damage to the plant by the withering of individual stems in a common bush:

brown spots appear at the ends of the leaves,
in some cases, the foliage becomes white due to a lack of chlorophyll in it,
the foliage of the upper tier turns yellow and curls,
the surface of the leaf plate becomes mottled,
the lower tier of leaves fades and becomes smaller, the edges of the leaves twist upwards.

Weakly affected by ring rot, potato tubers outwardly almost do not differ from healthy root crops, however, in the transverse size, yellow lines can be seen passing along the vascular ring, the tissues are softened.

Blackleg

The black leg develops under the influence of microbes that settle on weeds and then spread to vegetable crops. At the same time, the activity of microbes is maintained at a temperature regime from 2°C to 32°C.

signs

It is impossible to visually determine the presence of signs of damage to potato root crops in the early stages.

The black leg, according to the description, shows symptoms when favorable conditions are created for it in the form of increased dampness or excessive dryness. At the same time, among the most common signs of the presence of microbes, there are:

blackening of the bottom of the potato bush,
yellowing leaves,
general wilting of the plant,
rotting tubers with darkened skin and cracks,
liquid with a characteristic stinky odor.

As a result, in the basal part, the black leg begins the process of softening the sprouts, the potato tubers become covered with black spots and begin to rot. Infected bushes are easy to pull out of the soil layer. From the sections of the stems, mucous secretions are visible.

Measures to combat rot

Measures to combat various varieties of potato rot include treatment and preventive methods.

To prevent the activation of putrefactive fungi, compliance with the general rules for storing vegetables in the basement or at home on the balcony is of no small importance. Creating favorable conditions allows you to stop their activation, slowing down the development at the dormant stage.

General prevention

The main preventive measures involve a number of simple, timely measures:

the balance of fertilizers when growing potatoes, which allows developing plant resistance to diseases, avoiding an excess of nitrogen components and the mandatory inclusion of potassium,
the use of healthy tubers for planting, purchased from reliable sellers,
planting a vegetable crop in light soil, avoiding lowlands, where there is an excess of moisture,
avoidance of mechanical methods of harvesting, leading to frequent damage to tubers, rejection of damaged potatoes during storage,
planting green manure, acting as organic fertilizers,
compliance with the rules of crop rotation and storage of vegetables.

Prevention by type of pathogen

The control measures taken for therapeutic prophylaxis depend on the type of pathogen.

against brown rot

There are no drugs to combat dry (brown) rot. Planting material for protection against the disease is pre-treated with phytosporin (50 g per 100 kg), bactofite (up to 0.5 kg per 100 kg). Before storing potatoes for storage, vegetables are often treated with 0.2 liters of "Maxi KS" provided for 1 ton.

Against wet rot

Bacterial rot stops development if you create an optimal storage mode for vegetables - from 1 ° C to -2 ° C - and provide good ventilation. In such unfavorable conditions for pathogens, bacteria remain inactive. During storage, rotten root crops are removed along with neighboring ones.