Potato diseases can be very serious. Therefore, it is extremely important to be able to diagnose and treat them in time. Otherwise, you can remain completely without a crop. There are various diseases of potatoes.
Quite often there is such a disease as scab. This is a disease of potato tubers, which is also divided into several varieties. It can be ordinary, powdery scab, and sclerotia of rhizoctonia can also form on sprouts and tubers.
All types of scab have similar manifestations. So, the disease mainly affects young nodules, the size of which does not exceed 3 cm. The disease manifests itself in the form of sores and scabs on potatoes. And the more the fetus grows in size, the greater such ulcers become. This is how ordinary scab manifests itself.
Powdered scab is also characterized by the presence of protruding pimples on the tubers. There can be much less ulcers. Moreover, they may be completely absent. But sclerotia rhizoctonia usually include all of the above symptoms. Only dark spots on the fruits are added.
The causes of scab in all types of disease are exactly the same. The disease develops as a result of a glut of soil with fresh manure or fertilizers containing lime. Also contributes to the reproduction of pathogens drought. The bacteria that cause the scab are tenacious. They can survive in the soil for more than 3 years.
As for the treatment, first of all, it is necessary to provide potatoes with plentiful watering. There is no need to make a swamp in the soil, as this can lead to other diseases. But in no case should it be allowed to overdry an earthen coma. Ideally, you should completely change the soil and feed the plant as needed only with rotted manure.
To prevent this disease of tubers, potatoes should be treated before planting with a solution of copper sulfate and boric acid (dissolve 1 tbsp. Of each product in a bucket of water). And during the period of growth of tops, it is recommended to periodically spray plantings with zircon strictly according to the instructions that are written on the package with the drug.
To reduce the risk of scab damage to potatoes to a minimum, it is necessary to liming the soil exclusively in the fall, when the potato has already been dug up. And as the main fertilizer, make only rotted residues, which are already more than 2 years old. Such control measures will help get rid of the disease.
Potato late blight
One of the most infectious and common diseases of the culture is late blight. Spores of this fungus feel great and multiply in warm and humid weather. Therefore, gardeners should remember that both excessive watering and spraying in the summer can be harmful. After all, the disease affects both tubers, leaves, inflorescences and tops. An already infected late blight plant easily infects others, as a result of which the disease spreads very quickly.
The description of this disease is quite simple: you can see dark brown spots on the tubers, which are soft to the touch. If you cut off the skin, then the part of the potato under it will also be brown. Sometimes late blight affects not even areas, but 90% of the surface of the fetus.
Yellow or brown spots also appear on the leaves, which then pass onto the stems, becoming more and more bright. Inflorescences become very brittle and quickly fall off. As a result, if the late blight is not treated in a timely manner, the tops dry out very quickly and the bush dies.
Processing potatoes from diseases such as late blight should be carried out using fungicides. They need to spray the bushes when the first signs of infection appear. Some gardeners even prefer to spray completely still healthy plants for prevention. But this must be done with caution, since excess substances can adversely affect the quality of the soil and crop.
Practice shows that the most powerful and safest folk remedy for the prevention of late blight is a solution of manganese and garlic juice. For cooking, you need to take about 2 glasses of leaves or finely chopped cloves of garlic, pour a bucket of warm water and insist for about 3 days. Then strain it all through gauze, trying to squeeze as much juice as possible, and add about 1.3-1.5 g of potassium permanganate to the resulting liquid.
It is necessary to spray the tops with such a means thoroughly so that the juice falls on all the leaves and stems. All this should be done early in the morning or at night, when there is no strong wind, and the weather is dry and warm. It is ideally necessary to process potatoes with such a composition every 10 days.
In the event that the disease has already hit a culture, it is necessary to immediately begin more serious control measures. Initially, all the bushes are well treated with a strong systemic-contact fungicide. This is best done early in the morning or in the evening after sunset in dry weather. The dosage is calculated based on the instructions for the drug.
Repeated processing must be carried out after about 10 days. For this, one contact fungicide is already used. After another 10 days, if necessary, the last treatment for diseases can be carried out. It should not be forgotten that to finish spraying the tops with potent drugs you need at least 20 days before the start of the harvest.
A common disease is also a potato nematode. This disease often appears when tubers are not properly stored in the winter, and also when the crop has been grown for several years at the same place on the site.
A tuber affected by a nematode when stored improperly begins to decay strongly from one edge, and the root is covered with round growths. By external signs of land, the disease is easy to detect if the leaves and stems begin to fade, turn yellow and quickly dry out.
Potato nematode is able to live in the soil for 10 years and even more if the conditions are favorable. We must not forget that the nematode can be transmitted to healthy fruits not only through the affected soil, but also through the use of the same equipment, containers. Strong winds can transfer larvae from diseased potatoes to healthy ones, even if they grow relatively far.
Nematode is a very dangerous disease that rarely can be cured on its own. It is best to take care of prevention on time. Varieties that are resistant to such a parasite should be preferred. But even such tubers can become ill if stored incorrectly. Therefore, in winter you need to store potatoes in a rather dark and dry place, to prevent moisture from entering. If potatoes are purchased on the market for planting, you need to check them so that there are no putrefactive spots on the surface.
If it is found that the nematode has already wound up in the soil where the crop was grown or grown, it is best to immediately contact a special service. Alone with such a disease can not cope. Moreover, in most cases it is necessary to completely change the topsoil, as other control measures do not help.
Protecting potatoes from disease
Very dangerous are considered bacterial diseases. One of these diseases is the black leg. As a rule, when the potato is damaged by bacteria that cause the black stem, the stem becomes black at the base and can easily be pulled out of the soil without tubers. Sometimes, even when feeling, it is felt that inside it is empty.
The leaves quickly turn yellow and twist into tubes. Their infection occurs from the bottom up. As for tubers, they become ill last. Mucous white spots appear on the potatoes, which quickly affect the entire surface of the tubers. Then the potatoes become very light, emit an unpleasant odor.
This is a very insidious disease, since the tops can disappear in a matter of days, while the tubers will remain intact and will be successfully dug out of the soil. But the fact is that they can already be hit by a black leg. Only the disease will appear only after some time. And during storage, other root vegetables will become infected from infected vegetables.
For the prevention of the black leg, experts recommend spraying the tubers with a special fungicide before planting, and then carefully dry them. What kind of tool to choose, a specialist in the store will tell. After all, today there are many varieties of drugs in this category, designed specifically for preventive treatment.
The main control measures are to completely dig out the diseased bush with tubers and burn it all. The hole should be generously filled with a mixture of wood ash and copper sulfate. If other potato bushes grow nearby, it is recommended to sprinkle the ground around each bush with crushed charcoal, and treat the tops with a solution of laundry soap and copper sulfate (1 tbsp of vitriol and 40 g of soap dissolved in a bucket of water).
Potato Diseases and Controls
Viral diseases are also considered dangerous. One of them is alternariosis. Most often, alternariosis affects the stems and leaves of potatoes. Less commonly, tubers. This disease develops after a period of vegetation in dry, hot weather, usually in the middle of summer. The disease actively propagates on potatoes in the conditions of a catastrophic lack of moisture, with an excess of phosphorus in the soil and a simultaneous lack of potassium and nitrogen fertilizers.
Signs of the disease are black spots on the leaves, which gradually turn to stems. When tubers are ill, the same spots form on the surface of the fetus. The disease is very contagious, therefore it is easily transmitted from a sick plant to a healthy one even when it is touched or through the soil.
Alternariosis in most cases affects tomatoes. Therefore, planting tomatoes and potatoes next door is strongly discouraged. Particularly often, infection occurs during harvesting, as a result, potato disease can occur only during storage.
Measures to combat alternariosis are quite simple, although it is not always possible to completely get rid of such a disease. It is enough time to apply nitrogen, potassium and phosphorus fertilizers to the soil in the required amount, to ensure that there are no plants with weak shoots on the bed, and to maintain normal soil moisture.
As a preventive measure, it is recommended to periodically spray potato tops with universal fungicides, which can be bought at any garden store. You can spray with a solution of Bordeaux fluid. And every autumn you need to dig the soil very well and dig as deep as possible.
The listed main diseases of potato do not represent a complete list of plant ailments. After all, the number of diseases of vegetable crops is increasing every year, since bacteria and viruses mutate, becoming more resistant to standard methods of dealing with them.
Diseases of potato tubers, tops and leaves are all equally dangerous and contagious.
Therefore, it is recommended immediately after the detection of the first signs to take appropriate measures so as not to start the disease even more and not to provoke infection of all other plants. Prevention and timely diagnosis are the best things to help prevent disease.