What to do if there is late blight on potatoes. This is a terrible word potato late blight or we are fighting a misfortune. Protection of potatoes from late blight - video.
And how to deal with it, you can save the harvest.
Causes and signs of the disease
The causative agent of the disease is the pathogenic fungus of the same name. It belongs to the lower fungi (oomycetes).
The disease is transmitted through phytospores, which are washed off from the terrestrial part of the plant and through the soil capillaries enter the stem or tubers. The incubation period is from 3 to 16 days. On weakened soils or in the presence of microorganisms in the planting material, the fungus progresses very quickly, in 3-4 days.
Tubers are usually contaminated with grease infestation during harvest, when damaged or non-exfoliating tubers come into contact with infested soil, machine parts or tubers. Even during the growth of heavy rains, it can rinse zoospores from the grass into the ground, and then infect the tubers, this causes the so-called tuber or burn. Rapid extinction of stocks significantly reduces the risk of tuber infestation, long-term moderate infection of rotting grasses increases the danger.
Regulatory strategies: prevention and control
Grass rot - reduces infection and spreads
Plant seeds should be cut and planted on early stage, use the best technique and avoid layers resistant to late resistance. As a result, the time when the grass starts to rot is better used for the formation of the crop. Selection of plant tolerant varieties with early tubers and low nitrogen requirements. The susceptibility of varieties approved in Germany is assessed in descriptive variants.Rotting tubers - Reduce the transfer of grass to the tuber
During storage, avoid injuries, low drop heights, short transport distances and not too abrupt changes in the direction of transport, boxes instead of storage in a warehouse. It was found that agents that enhance the strengthening of plants have practically no negative effect on the disease.Tubers often get sick already during harvesting. If the diseased tops are in contact with their eyes, then part of the crop may die. With incisions, this risk increases significantly.
Important! An important preventive factor are. If the same nightshade crops grow in one place from year to year, the soil must be disinfected. Phytophthora as a viral fungus is very fond of moisture. A few rainy days with temperatures between 15 and 25 ° C are ideal conditions for it. A heap planting only enhances the effect: in such cases, even thick dew is enough. In hot weather, this ailment stops developing, but this does not make it easier for plants.
Direct control with authorized plant protection products
However, increased yields can be demonstrated in some formulations such as rhubarb tea. Introducing sage and burdock root into soil are promising strategies that warrant further research. Crop protection products based on copper hydroxide are currently approved. As a contact fungicide, copper can only protect itself against new leaf infections, but cannot fight a once established leaf attack.
Copper processing is often less profitable than anticipated and therefore not very economical, and many studies also show that the amount of effort can be significantly reduced. Therefore, the frequency of use and effort should be reduced as much as possible in order to be cost effective and to reduce unnecessary environmental impacts.
In most regions, characteristic lesions of the stem or leaves of potatoes can be seen in the second half of summer, although in the southern regions a few June rains are enough.
The danger is that even from several infected bushes, phytospores can spread to all plantings in 1.5–2 weeks, and if no action is taken, then after 17–20 days the plants die.
For some associations, the use is not allowed or is possible only with the approval of an exception. Swallowing and spraying at least 400 liters of water. ... Headline title: Why is Dad important to us? Potatoes are food plant which originates from crops to the Incas, the Peruvian territory has the greatest genetic variability of this crop in the world.
The varieties are classified as modern and native. Sowing and production in the Sierra is 95% and 90%. On the coast, the planting and production of potatoes is only 5% and 10%, respectively. The main pests affecting crops. Weevil weevil. Potato womb.
Late blight is dangerous for the entire Solanaceae family:,. In addition, this disease is affected by.
You can recognize the action of the mushroom by the following signs:
- spots appear on the edges of the leaves, which very quickly become brown and increase in size;
- white marks are visible on the bottom plate of the sheet - these are the spores;
- in rainy weather, the leaf can rot;
- on the affected tubers, gray spots are clearly marked, which also begin to acquire a brown color. They immediately harden and go deep into the fruit. If you cut such a potato, it will seem that it is "rusty".
Worm gear cutter. Treat with an application to the throat of the plant at the beginning of the appearance of this pest with Semivin. Major diseases affecting the crop. Black coast or sucker. Disinfect seeds and serenade leaves before peeling. Preventive uses with planting serenade and 3 foliage applications.
Wart. Potato golden nematode. Funnel of premnotripii: northern sierra. The female lays her egg at night in groups or rows of about 14 eggs per posture. Adults: Crescent-shaped foliage. Larvae: sterile tubers, causing them to rot, also perforate the tubers, leaving galleries that this damage occurs both in potato shops and in the same field.
Did you know? In some areas South America there are still wild potatoes. True, it is not suitable for food, since the tubers contain poisonous compounds of solanine.
How to carry out the treatment correctly (chemicals)
To ensure the harvest, you will have to deal with the prevention of sowing material, processing and planting.
Cycle: egg - larva - pupa - wintering adult - free adult. The larva produces galleries, but tubers, causing silky-covered galleries. It also attacks tubers in the field. Damage caused by moths. Damage to foliage and potato tubers.
What is rhizoctonia on potatoes
They attack shoots, leaves, weaken generalized growth, and endure shoots. Inverna species are related to the state of the egg. In the summer, by the end of December, winged forms appear and migrate to the papacy. By the end of March, populations migrate from the papacy, and men appear in them, where there is sexual reproduction. Subsequently, the eggs are deposited in the shoots or stems of other hosts.
Disease prevention
The main thing is to use well-groomed soil and healthy potatoes for planting.
As for the ground, it is advisable to choose an even one. A field in a lowland is not suitable - places with a large accumulation of moisture, as we remember, are potentially dangerous. The land should be well lit and ventilated, and normal will have to be provided.
Treatment or prevention?
Hosts: English Mint, Potato, Pepper, Tomato. Damage to the foliage and tubers of the salmon flea, the injuries that the larvae and adults produce, result in occasional plant death. The larvae destroy the roots and pierce the stem. Adults gnaw and pierce the leaves; Sometimes, several holes are attached. In addition, with normal leaf growth, the size of the lesion also increases. That, together with the reproductive ability of this insect, puts it in pests dangerous for cultivation.
Epitrikskumerizatsya atomizers - small bright black cockroaches, feeding on buds and foliage; damage is observed in the form of holes of different sizes or round and transparent scars in the bundle of leaves. When they are very numerous and the plants reappear, they destroy most of the deciduous area and the crop suffers significant damage.
Remember what grew on the site earlier - flax, and will be the best predecessors. The best "neighbors" will be either mustard, but it is better to keep other nightshades away.
Important! It is believed that severe frosts kill the late blight fungus in the soil. Unfortunately, the pathogen is slowly adapting to our conditions.- for example, in the southern regions, winter is no longer terrible for him, and it is advisable to cultivate the soil in the fall.
The larvae hide in the ground during the day and come to the surface of the ground at night, where they cut plants that are just above the surface of the soil. This is typical damage to most cut worm species. The larva cuts an average of five tender potato plants during development. When the soil conditions are dry, the larvae do not move to the surface to feed, but instead feed on the plant that is slightly below the soil surface. Rarely is this field completely destroyed, and serious damage is usually limited to areas of the field.
It is one of the pests of greater economic impact of a wide range of crops, which also attack hosts. It can attack crops at any stage of development with direct and indirect damage. Damage caused by white flies, loss of plant energy due to sucking by nymphs and adults, presence of dew syrup on the surface of affected parts as a result of removal and transmission of pests from yellow potato virus. It goes through the states of the egg, nymph, pupa, and adults; the duration of each state depends on temperature and humidity.
The fight against late blight of potatoes begins even before planting in the ground and at first comes down to choosing healthy tubers. It's easy to check them: for 2 weeks, the potatoes are heated in the open air at 15-18 ° C. Already at this stage, the first signs, such as spots, will become visible. It is better to put such material aside or immediately throw it away.
Eggs are deposited inside the leaf parenchyma; Creamy white maggots emerge from them, which cause damage, feeding them like mines in streamer form, and then large spots that dry out and stand out like burning on a leaf. Late pest attacks, especially after flowering, can lead to lower yields, so rapid control measures must be taken.
Most of the damage is done on foliage, but also affects tubers and roots. Slimes have nocturnal habits and live in colonies in damp and dark places. They are hermaphrodites and can self-cleanse. Mutual mating also occurs between humans, so at the moment they can act like males or females. Late burn, ranch, fungus ice.
Further prevention includes such measures:
- Primary treatment - formulations in higher doses. At the same time, the concentration of potassium compounds is doubled, while phosphorus preparations are given 1.5 times more than the norm.
- Deep planting of "seed" potatoes and hilling of young bushes.
- Grooves, not "".
- Cleaning of diseased plants growing on the site.
- Many people simply cut the tops about a week before harvest. True, even for strong bushes it is traumatic, and it is not worth delaying cleaning after that.
- Harvested in sunny, dry weather. Moisture only plays into the hands of the harmful fungus.
Rancha affects the leaves, stems and tubers of the potato plant. In the leaves. - The disease begins with small, irregular patches ranging from light green to dark green. These small irregular patches, which usually develop at the edges and apex of the leaflets, grow rapidly, resulting in large brown and black necrotic lesions.
In tubers. There are depressions on the outside of the infected tubers. Damage. Tubers used as seeds do not appear when sown on infected soils. In the same way, apparently, healthy seed tubers develop in favorable conditions of soil moisture, but the shoots die, the root and root rot of the mother tuber develop little.
Potato treatment
Late blight of the bush in the active stage cannot be cured. This is true, but the focus of the disease can always be "localized" without allowing spores to spread to healthy bushes. Various solutions and help with this.
Did you know? In the 18th century, potatoes were considered "earthen". In 1758, the Academy of Sciences in St. Petersburg even published an article on its cultivation, and this name is indicated there.
Rhizoctoniasis, black coast, sucker. The disease affects only young tissues of shoots, stems and stolons. The disease affects the shoots of the seed tuber in pre- and post-emergency conditions. Affected shoots show brown necrotic lesions at the base, which when suffocated deeply. However, even in this state, the plant can develop from the lower part of the strangled trunk, new outbreaks.
The disease attacks stolons, causing necrotic lesions that can suffocate or kill them. When this happens, the tubers that are fully developed remain small. The disease affects the roots and, as a result, causes a rash of the apical leaves.
After planting, they are waiting for the tops to grow up to 25-30 cm. best time for the first processing. "Factory" system means like "Ridomil" are used.
Just before flowering, they are sprayed. For resistant varieties in warm weather without rain, "Immunocytophat", "Silk" and "Krezatsin" are more suitable. If the disease still manifests itself, take "Ridomil" (MC or), as well. For the best effect, the treatment is repeated after 1.5–2 weeks (but always before flowering).
When plants develop in infected soils, a gray-white mycelial layer is observed at the base of the stems. On the surface of the affected tubers, black crusts, called sclerotia, are present, which are the fungi retaining structures.
The disease affects pre- and post-emergence seedlings from botanical seeds. Affected plants become small, show chlorosis in the leaves of the lower quarter and necrosis in the root collar. The mycelium of the fungus causes root rot and partially or completely covers the roots and stems of the affected plants, causing non-tuberization.
After 8-14 days, carefully examine the bushes. If the risk of infection remains high, take strong ones such as "Ditan", "Revus", "Efal". For prevention (if there is no focus of infection), they are mixed in half. Note that the drugs should be exactly contact - phytophthora quickly gets used to the systemic fungicide.
They are covered with white mycelial growth, which leads to rotting and death of the shoots. During harvest, the affected tubers represent rot and mycelium development, which covers them in whole or in part. The presence of sclerotia in stems and tubers. The whitish mycelium, covering the surface of the stems and tubers, takes colormomiso and forms blue and sclerotia.
Scab is a disease that affects the quality of the tubers, but not the yield. Symptoms The disease affects roots, stolons and tubers, but does not affect foliage. The roots of the affected plants show gills or smooth tumors ranging in size from 5 to 5 cm and more or less irregular; tumors are whitish at first, and when they reach physiological maturity, they become dark due to the brown color of the walls of the resting sporangia.
After flowering, "Bravo" is suitable, with which the bushes are treated with an interval of 7-10 days. As for the tubers, Alufit helps them.
Important! At the end of July and in August, beds in the evening are possible. And also vitriol is very popular. For 3.3 liters of boiling water in separate containers, take a tablespoon of these ingredients. After allowing the mixtures to cool, everything is poured into a 10-liter container. Processing is done twice, at the very end of July - early August (with a break of 7-10 days).
Soda also helps get rid of phytophthora. It is part of a homemade fungicide. Taking 1 tablespoon of baking soda and 3 tablespoons vegetable oil, they are dissolved in 5 liters of water, after which 1 teaspoon of liquid soap is added. All this is mixed and immediately applied on site.
Stolon infection occurs in parallel with root infection and the symptoms are similar to those of the roots, but the gills are smaller. Diseased tubers show pustules that are initially smooth and whitish in color. Pustules can attach to larger areas of infection to cover more of the tuber surface.
Facts from history
Common scab. The disease affects the underground organs of the plant. Pustules or lesions raised in a circular shape, a type of crust, Brown color Sunken damage or semi-solid cavities. Necrotic lesions in the form of multifaceted figures. ... Diseased plants exhibit hypertrophy or carbonic tumors that develop on stems, stolons, and tubers. Tumors externally have an irregular surface with protruding lobes and deep depressions.
Did you know? was not immediately adopted in Russia- on the decision of the authorities to increase the planting of potatoes in the middle of the 19th century, a wave of "potato riots" swept across the country. But gradually they got used to it, and by the beginning of the twentieth century, potatoes began to be called "the second bread".
You can also fight this ailment with the help of "sour milk": 1 liter of already sour kefir is poured into water (10 liters), stirred and insisted for 3-4 hours. After straining, the mixture is ready. Use it with a week break until all spores and spots disappear.
Important! To avoid waterlogging, the floors in the cellar are covered with gravel or pebbles. But expanded clay does not give such an effect.
Some people practice, but this laborious work requires a regular presence at the dacha: if the site is visited 1-2 times a week, then there is no particular point in it (the cover must be removed daily after the dew melts). It is better to evenly sprinkle the furrows with a thin layer of lime - 1 mm will be enough.
The most resistant to late blight varieties
Even before choosing a planting material, it is better to choose a suitable potato. There is one point here: none of the varieties has a complete guarantee of safety - different lines differ only in resistance to disease. Of course, we need the most resilient ones. These are the varieties:
- "Nevsky" - smooth oblong tubers with a pure white "gut" are great for different dishes;
- "Vesna" is a very early variety, loved by many, with good immunity and enviable taste;
- "Luck" is a mid-season line, which is distinguished by a long period without loss of its qualities;
- "Red Scarlett" - a longish red root vegetable is almost immune to the action of phytophthora and is well preserved.
Did you know? Potatoes can be safely called a space culture. In 1995, she became the first "garden" species to be grown in orbit.
In this regard, it is considered more profitable early varieties: late blight simply does not have time to ripen, and the crop can be removed with virtually no loss. With later plantings, there is more work, especially since new non-standard strains appear every season.
Potato storage rules
The potatoes harvested in dry weather are dried and sorted. Whole roots are left without processes. In this case, the damaged tubers are laid separately, they will have to be thrown away.
Most often, potatoes are stored in basement... It is advisable to do harvesting there, paying special attention to old tubers and shoots - an infected potato will be a bad neighbor for a new crop. The cellar itself must be well ventilated.
It is also not worth neglecting the whitewashing of the walls, especially since it is easy to do: just take 10 liters of water, 2 kg of slaked lime and 1 kg of copper sulfate - and the mixture is ready. Some also add 150 g of common salt.
Important! To save the harvest, they try not to abuse lighting. Light activates the production of poisonous solanine in root crops.
Container plays an equally important role. In most cases, these are boxes. They are dried, processing with potassium permanganate will also be useful. Already filled boxes are placed so that there is a gap of 10 cm between them, and at least 25 cm to the wall. They are placed on a small (20-25 cm) elevation of boards or bricks, but so that there is enough space from the top for ceiling. Deaf boxes will not work: a gap of 2-3 cm is needed between the slats for ventilation.
The nets, in turn, provide ventilation, and the burlap retains heat.
During storage, they try to adhere to the following rules:
- compliance with the temperature regime;
- insulation during prolonged frosts; straw is best, but old warm clothes will also work;
- periodic inspection of containers and the potatoes themselves;
- closer to spring with thaws, it is advisable to move the boxes (water often penetrates into the basements, which leads to the death of root crops).
Did you know? The importance of this crop is evidenced by the fact that the UN special commission called 2008 the year of the potato.
We learned what late blight is in potatoes, received a description of this disease and gave the main methods associated with the treatment. We hope this knowledge will be useful to our readers. Good luck in the beds!
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Phytophthora is a mushroom that grows and develops on nightshade crops, that is, tomatoes, peppers, potatoes, eggplants and physalis. The mushroom is most active with excessive humidity, fog, a strong decrease in temperature at night, and an increase in the daytime, a large density of plantings. It also appears if tomatoes are grown very close to potatoes. The disease looks like fuzzy grayish-brown spots on the leaves, stems and fruits, under the spots inside the tissue they have a light brown color. Affected fruits should not be eaten.
Soil treatment
In winter, at subzero temperatures, most of the pathogens of late blight in the soil are destroyed. But you need to make sure that there are no old stems, tubers left on the site, burn them.
It is advisable that the potatoes do not grow in the same place for about 2-3 years. Mulch the soil. You can treat the ground with EM-5 or Baikal EM-1 solution to remove the remaining fungi of the disease.
Selection of material for sowing
Scrupulously review the planting material, removing diseased tubers. Before planting, be sure to arrange the tubers by varieties so that you can then plant them in different beds.
Varieties Charodey, Elizabeth, Petersburg do not suffer from late blight. If you choose them, then you can be calm.
Sprouting tubers
Rinse and dry the potatoes before germination. The tubers must not lie in the water, they can rot. Sprout the tubers in a room with plenty of light, which is well ventilated.
The air temperature in the room should be +10 ... + 15 ° С. Place the tubers in the boxes in two layers. After a while, turn the tubers over, then they will grow good strong sprouts. Rotate the drawers in different directions for better lighting.
Treatment of tubers from late blight
In order to harvest an excellent harvest as a result, you need to carefully consider the treatment of tubers before sowing. Spray the potatoes with the copper sulfate solution every seven days. Take a bucket of water (10 l) and add 2 g of copper sulfate there, or spray the potatoes with a solution of potassium permanganate diluted in the same proportion.
Before planting tubers from late blight, treat with the composition "Fitosporin M". Dilute 4 tbsp. tablespoons of the substance in one and a half glass of water. Spray 10 kg tubers with a solution. You can also dip Imunocytofit tablets (a 3 g tablet per 1 liter of water) or Agatom-25K (12 g per 1 liter of water) into the solution. You can process the tubers before sowing with the compositions Maxim (dilute 4 ml with 0.05-0.1 liters of water - this is enough for 10 kg) and Celeste.
Potato planting processing
If you have already planted potatoes, your tops have grown and you noticed phytophthora on it, then you can spray it with Oksikh, Hom, Ordan, Bravo. After one spraying, wait 10 days and re-spray.
If the potato plantings simultaneously fall ill with late blight and alternaria, then they need to be sprayed with the Translamyral-systemic two-component fungicide REVUS TOP. Take this into account.