Powdery mildew control measures on currants

Mealy dew is a fairly common disease on the bushes of black, white and red currants, which can destroy not only the entire crop, but also the plants themselves. Therefore, it is necessary to take preventive measures in time, beginning to actively deal with dew in the initial stages of the disease. With proper and timely treatment there is a chance to save the fruit and berry bushes of the plant, to keep the crop safe and sound.

Currant bushes are small, some of them can reach up to three meters in height. The twigs are supplied with bright green toothed leaves with a pleasant aroma. Currants love sunlight, but it also grows well in the shade. Fruits - berries can be black or red, as well as colorless (white currant), have a characteristic pleasant smell and sweet-sour taste. They are used to prepare various desserts and sugary drinks.

Currant fruit is rich in vitamins and trace elements. Irreplaceable organic acids and flavonoids are also found in the leaves and flowers of the red and black currants. The pigment in the berries contains anti-cancer elements - anthocyanins.

All varieties and types of currants are subject to various diseases, such as anthracnose, goblet and columnar rust, white spot and gray rot. But also among the first dangerous diseases of currants - European (American) powdery mildew. The disease first affects the younger parts of the plant, and then moves to more mature stems, leaves and fruits. The disease is a fungal infection. Its appearance is caused by the activity of the Sphaerotheca mors-uvae microscopic marsupial fungus.

The parasitic fungus slumbers off to sleep in the upper buds and parts of the currant stems. With the onset of warming, it begins to awaken and actively reproduces. In April, ripe disputes are carried by the wind in millions of clouds, infecting large areas of berry plantings. The mycelium itself blooms in June, along with the establishment of heat and optimum humidity.

Under favorable conditions, such as high humidity (more than 80%) and temperatures above +20 degrees Celsius, the areas affected by fungal infection increase. As well as the spread of the disease are excessive nitrogen input, abundant frequent irrigation and lack of ultraviolet radiation. Genetic plants are more likely to become ill with the sphere library.

Crawling and flying insects carry spores from plant to plant, infecting currant bushes one by one. Microscopic infection spreads rapidly with rainwater through the soil and when watering plants.

The fungus infects all the cells, parts and tissues of the plant, absorbing carbohydrates and poisoning everything around with products of its vigorous life activity. It appears mainly after flowering, striking young branches with just dismissed leaves. On affected areas, a mealy patina is detected. The leaves are deformed, wither and blacken, the berries gradually lose their color and fall.

Currant bushes are covered with characteristic lesions, the plant first begins to lag behind in growth, then ceases to grow and dies. Berries become unsuitable for food, moreover, their use can provoke allergic reactions and dangerous conditions in humans. Without human help, a plant cannot get rid of this dangerous disease.

It is not for nothing that the fungal parasite is called the “black death”, because mealy dew loves black currant more. Redcurrant is not as susceptible to this disease, which can destroy up to 80% of the crop. To combat the parasite apply effective measures and comply with the rules of agricultural engineering.

The sphere library is a rather common phenomenon on currants.At first, white bloom appears on the lower parts of the leaves and looks like flour, then it spreads in the form of small swollen spots, covering the upper parts of the plant, apical buds and young shoots. Then, the affected areas are compacted and darken like a felt. This is due to the fact that the mycelium enters the phase of the formation of glistenoteci - bodies that are ready for reproduction.

Sheet plaque goes up along the veins, young shoots are affected from above to the tenth leaf. All tissues are affected, including the sleeping lower kidneys, which, on awakening, immediately become ill. In the primary period, the disease is transmitted by suckospores. Next, the mycelium develops and enters the condal, and then - in the marsupial phase. Summer or condal spores are formed on the outer epidermis of the mycelium. They are able to be transported from a diseased plant to healthy naturally or through insects.

The marsupial microspores in cleistothecia begin to form in July, and fully mature only in the spring of next year. Wintering spores are activated with the onset of heat. Their growing season usually ranges from one to one and a half months. The output of the dispute coincides with the phases of flowering and the appearance of the first ovary on the currant and falls in May - June.

The formation of fungal colonies and infection of fruit and berry bushes occurs at temperatures above +17 degrees with a relative humidity of about 80%. In a wet environment, mushrooms do not grow, they do not like too high temperatures. Above +30 degrees Celsius, they stop giving out external signs of life activity. Peaks of the disease occur at the beginning of summer and immediately before fruiting. Moreover, only new shoots of 10 days old, as well as fruit ovaries, 40-day stems and leaves are not affected by powdery mildew.

During its life cycle, the candidate gives 10 generations a dispute. Plants with a fast growing season are less susceptible to disease, so redcurrants are less likely to get sick than black ones.

A diseased plant is easily identified by its appearance.

White filaments of mycelium, called mealy patina, appear on different parts of the plant. It really resembles sticky flour. And dehydration of plant tissues also occurs, colorless oily droplets of false dew protrude on the leaves, the leaves lose their shape and coagulate. Next, the fruits are covered with rusty brown bloom, the stems and internodes bend, then the plant loses its epidermis, and with it the protection and immunity.

In the future, currant stops the growth of shoots and the development of inflorescences, its vegetative period stops. At the first frost, a weakened plant loses growth shoots and buds, and with the onset of heat it becomes unviable. Nothing remains but to dig up and dispose of the remains, in order to avoid contamination of other plants. If you do not treat the plant on time, you can lose berry bushes just for the season.

Most varieties of currant such as Silver Black, Goliath, Minai, Sugar, Dutch Rose, Black Eyes and others are most affected by powdery mildew.

The rapid course of the disease and the loss of the harvest force to take concrete and urgent measures. To get rid of powdery mildew, they begin to process the plant in spring, even before the first leaves appear, without waiting for the summer, when the temperature range favorable for the spread of the disease is established. To do this, there are many effective ways from the use of special preparations and ending with folk remedies. Various control measures against infection in one way or another contribute to the inhibition of the reproduction of the fungus.

To get rid of the infection you will need at least three campaigns in a row using effective means and comprehensive measures. It is best to treat the plants in cloudy, windless weather so as not to destroy the young shoots of the plant. Currant leaves should be sprayed on both sides, making sure that the sun does not fall on the plant after processing for at least three hours. The sprayed bushes are watered only after three days, therefore, before processing, it is necessary to water the plants well and make a little podgadat so that there will be no rain soon.

It is necessary to fight parasites using the rules of agrotechnology.

Experts advise to adhere to the basic rules.

• Plant currants in well-lit, spacious areas, avoid the shady sides under the trees.
• Do not allow affected plants to come into contact with healthy ones. To do this, they should be seated away from each other, far from other cultures.
• You must first remove the affected part of the bush, and then only treat it with special preparations.
• Prompt fertilizer in the spring, combining them with organic matter and phosphorus-potassium compounds, which greatly strengthen the immune system of the plant and accelerate its growth and vegetation period.
• To replace the soil layer with new humus every planting season.
• It is necessary to begin to spray currant bushes with chemicals, not waiting for the first messengers of the disease, and also to use folk remedies for the prevention and control of fungal disease.
• Do not water the currants with water, which has long been settled in closed containers. There may be pathogens and pathogens.

For the treatment of the sphere library, various methods and folk remedies are used. Their use is safe for plants and the environment, and the right ingredients are always at hand. Sometimes they treat it like that. So, to get rid of the pathogenic fungal bacteria, lactic acid bacteria are often used. The method of spraying currant with whey is well carried out in a complex, in several stages, for which it is necessary to calculate the time when there will be no wind and rain.

It is necessary that the solution could cover the surface of the plant with a medical film. For maximum effect, ten drops of a 5% iodine solution are added to the healing solution (liter of serum per bucket of water). It will take several approaches twice every three days to completely clear the plant of infection. Milk bacteria prevent the growth of mycelium and destroy disease-causing spores, not giving them a chance to re-infection of the plant.

Well helps steamed ash composition with soap. The method is based on the effect of alkali, enhanced by nitrogen under the influence of high temperatures. They take two kilograms of purified wood ash to a bucket of water, heat on the fire for half an hour to a boil, then add 30 grams of laundry soap to the solution, cool it and only then treat the affected parts of the shrub.

But you can also spray currants with a mixture of soda and soap. In 10 liters of water they dilute a couple of dessert spoons of soda ash or baking soda, half a glass of laundry soap in the shavings and mix everything well, then irrigate the currant bushes with a mixture.

Herbal infusions are successfully used to combat infectious diseases of berry bushes. Experts advise the use of infusion of horsetail and iodine at the rate of 100 grams of dry matter per liter of water plus five drops of iodine solution. A pinch of potassium permanganate is also added to the finished infusion, after which the composition is applied to the affected parts of the plant, including the soil cover under the shrub.

An effective mixture of five grams of copper sulphate per glass of water. The solution is added to a bucket of water and then irrigation of diseased plants is performed. Against the fungal infection is also used crystalline iron (iron vitriol). The mixture of copper and iron sulphate strengthens its action many times: 100 grams of copper and 200 grams of iron sulphate are taken to a bucket of water. Salts are carefully diluted in water and filtered. The prepared composition is impregnated with shoots, stems and buds before flowering, not forgetting the soil cover.

There is an old method of irrigating fruit bushes hot - up to +90 degrees - with water. It is carried out in the period of early spring, just watering the plants with heated water, which contributes to the destruction of sleeping pathogens and overwintered pests.

Powdery mildew is also fighting with infusions of fresh manure and weeds. A liter of organics insist in water for three days, then it is diluted and topped up in a bucket, with this composition watering the plants abundantly. Weed grass is poured with water and infused for 24 hours. Infusion is added to the solution with manure. When treating currant bushes with this compound, special attention should be paid to the affected places, and even healthy plants should be irrigated for prophylactic purposes. Colloidal sulfur is among the safe substances against infection. Processing it is made in the period of formation of buds, before the appearance of the fruit ovary.

You should know that the so-called folk remedies against the fungal parasite are good in the initial stages of the appearance of the disease.

For a safe range of drugs include brine, "Planriz" and others. They are not included in the number of chemical and do not have a caustic effect on the fruits and leaves of the plant. They are beginning to be used in early spring; special formulations are prepared with which the currant bushes are carefully treated. At the very beginning of the disease, plants are sprayed every three days. In difficult cases, copper oxychloride is connected: a teaspoon per half a bucket of water or a Bordeaux mixture.

Fungal infection successfully eliminates biofungicides containing beneficial bacterial strains of Bacillus subtilis. These drugs are absolutely harmless to people and animals, as well as to beneficial insects, they act only on pathogens of infectious diseases. Therefore, they are calmly used even during the flowering and fruiting of berry bushes. Among the minuses is a short period of action, ending immediately after watering or rainfall. With a duration of action of fungicides up to three weeks, they are used every three days for plants with particular susceptibility to fungal infection. Healthy bushes need to be treated with the drug at least once every two weeks for prophylactic purposes.

For the treatment of fungal infections, it is necessary to take urgent measures, for example, irrigate currant "Fitosporin-M". This is a non-chemical, fast-acting bacterial drug that can block the growth and reproduction of dangerous microflora. It is effective at the onset of the disease. Currants begin to be treated with the drug before the appearance of the leaf overgrowth of the prepared composition: five grams of the drug in powder are diluted with a bucket of water. For a lasting effect against powdery mildew, they also use drugs Previkur, Topsin, Raek and Scor.

When using chemicals, you must strictly follow the instructions and do not exceed the specified dosage, otherwise the plant may receive severe burns and lesions. Therefore, they should be applied in early spring or autumn. It is necessary to use special gloves, a mask, as well as to use all protective measures, including spraying in calm weather. When carrying out sanitary trimming of currants, it is necessary to disinfect the tools and process fresh sections with the Nitrafen solution.The same composition treats the soil under bushes and other surfaces and objects in order to disinfect and eliminate lesions.

Trichodermin, a ready anti-infective compound, destroys mycelium growth, additionally supplying the soil with nutrients. The drug is available in powder form. To prepare a solution, 100 grams of the drug is diluted with half a bucket of water. The resulting solution is irrigated and watered currant bushes. Means also process saplings before landing on a constant place.

Active compounds "Topaz" contribute to the destruction of the spores, preventing their germination. At 10 liters of water you need only two milliliters to prepare a weak solution for irrigating the bushes of the plant.

The fungicide "Fundazol" not only destroys the fungal infection, but also heals and protects the plant, helping to restore the affected cells and tissues. Spraying currant bushes with a solution of 10 grams per 10 liters of water before flowering and after harvest, you can protect the plant from the parasite fungus.

Remember that even if there are no signs and precursors of the sphere library, this does not exclude its appearance at any moment. Only the use of preventive measures can prevent a dangerous disease.

For the prevention of fungal disease should follow the basic rules and expert advice.

• Currant bushes need to be planted in a clean area, telling moderate watering, irrigation and timely fertilizer without excess nitrogen, providing a sufficient amount of light.
• You should not water the bushes from above, it is enough near-bottom infrequent watering. Do not over-wet the soil to prevent mold and mildew.
• Do not compact currant seedlings, do not plant bushes close to each other. Try not to plant cucumbers, gooseberries and roses nearby.
• Removal of the upper parts of the shoots in the fall will help to avoid infection with disease spores. All cut parts must be burned, and the cut sections must be treated with fungicides. Only then can one dig up the soil with fertilizers between the rows and directly under the currant bushes.

• In spring and summer, we must ensure that weeds do not appear near the bushes, as they can be carriers of the parasite. For these purposes, use of herbicides.
• When planting new currant bushes is better to use varieties that are resistant to fungal infections. These include varieties such as Charm, Titania, Exotica, Dachnitsa, Dobrynya, and others.
• It should choose only healthy bushes. When planting and caring for plants, it is necessary to use disinfectant solutions for handling inventory and the plant itself.
• Try not to store and dispose of all plant residues from the site so that they are not a breeding ground for fungal infection.
• Applying phosphate-potassium fertilizers, you significantly strengthen the plants, giving them resistance to pathogenic microflora.
• Making pruning plants in the spring, should not be removed in order to rejuvenate all shoots. Pruning in active mode will significantly weaken the plant, increase the wound surface, and currants can catch the infection. Therefore, you should not deprive of its natural protective properties in this dangerous period.

Taking timely measures of prevention and treatment will not only protect the fruit and berry bushes from powdery mildew, but also contributes to the ecological balance on the site.

How to deal with powdery mildew on currants, see the next video.