How to cure oidium on grapes. Measures to combat oidium in grapes. Folk remedies in the fight against powdery mildew
- Cause and symptoms of the disease
- Ways to combat the disease
The most common disease is grape oidium; all winegrowers who want to get a good harvest need to know how to combat it. In the fight against diseases and pests, the main thing is to promptly determine the reason that prevents the grapes from growing quietly. And for this you need to know how the disease manifests itself and what methods to fight it.
The most important damage is in clusters, as strong attacks cause the growth of the skin to stop so that it cracks and the fruit splits. There are also severely damaged grape shoots, and gray rot is preferred. Powdery mildew reduces the yield and quality of table grapes. In winemaking grapes, it significantly modifies the qualities of must and wine, reducing soluble solids, color intensity, and increasing overall acidity.
The present work was carried out in grape fields in Guadalupe, Baja California. The goal of development is to find environmentally friendly alternatives aimed at preventive treatment diseases. In terms of achieving results in brix increments, per last stage silica applications have been used for cultivation, achieving satisfactory results.
At the first sign of grape disease, you should immediately take necessary measures, otherwise you may lose all your plants.
Cause and symptoms of the disease
The cause of oidium on grapes is a fungus that affects all parts of the plant: leaves, shoots, inflorescences, bunches. The affected areas become covered with a gray coating, the berries stop growing and crack, and appear on the shoots. dark spots , which turn black very quickly. A gray coating also appears on the leaves, covering them on both sides. The fungus first attacks top part
Use green pruning to increase aeration, as it creates an environment that is not very favorable for fungal development and, on the other hand, facilitates the penetration of fungicides. -Removal of damaged edged wood with spots on branches at the end of vegetation. - In the chemical fight against powdery mildew there is wide range products and control strategies.
What is tree worm and how to identify and treat it. Odium is a fungus that is easy to diagnose. It appears in the form white powder or the very typical ash, leaves, buds, and also fruits. The leaves and stems are attacked, turning yellowish and eventually drying out. It is less common in flower.
A gray coating, gradually turning into dark spots, also appears on the shoots. You can see them after the vine becomes woody. Affected vines develop whitish-colored branches called “flags.” On the shoots, the fungus penetrates into the developing eyes.
This is very common fungal disease and causes serious damage. For example, in Rosal he appears year after year. Many farms grow roses to detect the onset of a powdery mildew problem before it is cultivated. Fungal spores are transported by the wind and fall on the leaves, cross the epidermis and germinate. There they introduce some roots to absorb nutrients.
Some plants are more sensitive to powdery mildew, but in general almost all will suffer from its attack if it prevails. favorable conditions. Rosale, Royal Laurel, Evonym, Oak, Shadow Banana, Jupiter Tree, Geranium, Dahlia, Phlox, Begonia, Hibiscus, Saintpalia, etc. very sensitive to give some examples.
The leaves of grapes are most often affected by diseases.
If you cut the eyes of grapes, the oidium can be seen in the form of threads located between the green scales near the future bunches. Under such “protection” the fungus calmly tolerates severe frosts and bad weather. Attempts to destroy the fungus in the eyes lead to their damage, which affects the harvest. The disease can affect buds before flowering begins. Over time, they dry out and fall off.
The peach tree is the most vulnerable. In apricots, cherries and plums this is less serious. Also, the fruits are covered with white and round spots. Peaches, cherries and plums are no longer edible. It maintains very wet springs and mild temperatures. They do not need liquid water for their development, but moisture. This can become very serious depending on the area. In farms near the river, humidity is higher and attacks are more severe.
This affects weaker plants and those in the shade, in fact placing plants in the sun can be enough to make them disappear. Remove weeds from all sides. Correguela is a grass that always has powdery mildew and it is carried to our plants by the wind.
Oidium on green berries is especially dangerous. It appears in the form of star-shaped blurry gray spots. The development of the disease provokes a cessation of berry growth. If the berries continue to grow, their skin hardens and cracks, exposing the seeds. This is especially noticeable before the start of ripening. An outbreak of the disease provokes the appearance of unpleasant odor mold.
Remove leaves and infested parts to prevent them from contaminating others. Remove any remaining plant debris. Enclosed areas, such as greenhouses or screened-in patios, must have good ventilation. In places where the disease is not chronic, you can wait until we see the first symptoms and treat with sulfur.
It's cheap and also stops ticks. Apply sulfur early in the morning or late evening to avoid burns that can occur in high temperatures. As a general rule, it should be taken into account that sulfur will be produced after treatment with Caldo baldols, and not before, to avoid burns.
The “best” time to attack grapes with oidium is a dry, hot summer. The disease rapidly affects plants, spreading spores even with the slightest breeze. Only cool, rainy weather can slow down the development of the fungus.
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Ways to combat the disease
Sulfur, used in various forms, is considered to be an effective means of combating oidium.
The strategy is to use contact fungicides initially and follow-up treatments with systemic fungicides. Oidium is an external fungus, grows on the surface, does not penetrate the leaves and can therefore be treated curatively with fungicides once it becomes infected. Other fungi penetrate the leaf, and fungicides serve only as a preventive measure to prevent them from becoming infected. Because once they're inside, there's not much that can be done.
If the plant is already infected, there will be no choice but to turn to systemic fungicides. Sulfur is a cheap and effective antioxidant that also kills mites and serves nutrient. We reserve the best when the white fungus is already visible. There are other sulfur-based phytophilizing formulas that have been developed for systemic use as an oxidostop that may be a good alternative.
Sulfur is sprayed onto the foliage and vapors are released when exposed to heat. The finer the grind of the drug, the better its adhesion to the plant. A fine dispersed form of sulfur, interacting with fungal cells, turns into hydrogen sulfide, which is a toxin for fungal spores. Treatment must be carried out as close as possible to the lesions.
Since this is a disease that affects the young part of the plant and the plant is constantly growing, preventative treatments sulfur or systemic products should be performed frequently. The treatment will be repeated at each reappearance. The fungus develops on leaves, buds and fruits, showing typical white floury spots in them. The most important reasons are the fruits.
This requires high humidity for infection, but not liquid water. Spring is ideal for this. The eraser can coat leaves, clumps or branches and causes deformation, curling of leaves and cracking of grapes. The inoculum is carried by the wind and penetrates through the stomata of the leaves. This can cause significant damage to small grains.
It is necessary to treat the vine before bud break to prevent the disease from appearing on green shoots. So that the treatment brings greatest effect, pollination should be carried out at temperatures above 20 degrees Celsius. Treatment in cold weather will be ineffective.
Powdered sulfur does not adhere well to the plant and can be washed away by rain. But at the same time, it is able to penetrate inside the bush and provide a high vapor density and a strong fungicidal effect, especially in warm weather. If powdered sulfur is simply applied to the soil around the bush, then the effect of its action can only be observed with very high temperature air.
What are the symptoms of powdery mildew on young shoots?
Was the first disease of American origin introduced into Europe and for a long time called "grapevine disease". It is present today in all vineyards. In spring, symptoms of powdery mildew are observed: slow growth, reduction of internodes and crispness of leaves. White felt may appear on very sensitive varieties: these are “flag” symptoms.
What are the symptoms of powdery mildew on leaves?
The most early manifestations Powdery mildew is characterized by oily spots and blackened veins on the underside corresponding to necrotic cells. Then a grayish and dusty felting appears on the spots. upper face, as well as the clarity of the edges of the limb.
Preparations based on powdered sulfur help fight severe outbreaks of the disease. This is the only means of plant protection with highly developed vegetation. One of the most effective means sulfur color is considered to be a very fine yellowish powder.
What are the symptoms of powdery mildew on grapes?
The grains are first covered with an ash-gray dust. Under these fruits the organ remains green, then the cells die and the berries burst under the pressure of the developing cells. This gap is reflected characteristic appearance seeds and creates a gaping door for botrytis. The painful tufts emit a strong “mouldy” odor.
What are the symptoms of powdery mildew on grapevines?
What is the biology of the fungus associated with powdery mildew?
Mycelium in the buds, providing early contamination of the shoots of cellular stacks formed on the attacked organs. Cleistothepy broke out in the spring, releasing ascospores that provide primary contamination. Ascospores and conidia from the mycelium colonize various organs. Powdery mildew, unlike downy mildew, is a parasite external to the vine, so the mycelium is on the surface of the organs and must emit suckers for anchorage and feeding, and powdery mildew spreads to conidiophores bearing conidia dispersed by the wind.In hot weather, you can use ground sulfur. It is less effective and prone to clumping. To avoid this, it is necessary to add at least 15% fillers to it. Kaolin, talc, and lime are used as fillers. They help reduce burns on the plant that are caused by high temperatures.
You can also fight the disease with liquid sulfur preparations. They are perfectly distributed over the foliage and stay on it for a long time. This allows you to get positive effect from treatment, even if spraying was carried out in unfavorable weather. More often liquid products used as preventive measures. The maximum effect of their influence is observed on initial stage growing season. As the plant grows, their effect weakens because liquid sulfur lingers on the upper part of the leaves, and the fungus develops in hidden places: on the leaves inside the bush. That's why the best method control of the disease during this period will be pollination.
The presence of free water disrupts germination and ruptures conidia. The sensitivity of the cluster is “late color - early fruit set”. Last week we saw the emergence of major grapevine diseases and, in particular, phylloxera, which forever preserves the memory of the world of wine. This week we look at other common illnesses.
There are two main types of grape diseases: fungal and insect. Diseases associated with fungi. The two most common diseases of this type are mold and powdery mildew. Two diseases that directly affect the yield and more indirectly the quality of the grapes.
Treatment of grapes with sulfur-containing products is carried out in the morning or evening. On hot days, burns may appear on the leaves and fruits. A solution for treating vines is prepared in the proportion of 80-100 g of the drug per 10 liters of water, for preventive measures 25-40 g of the drug are dissolved in 10 liters of water.
Mildew: This mushroom grows on leaves. This results in direct damage to the vine, causing deformed shoots, tendrils and clumps, or causing leaves to fall prematurely, increasing the vine's vulnerability. The disease develops especially in spring and early summer when it is cool and wet. The most natural treatment is basically a "Bordeaux mixture", a solution of copper sulfate and lime, or, less naturally, by chemical treatment.
Powdery mold: a fungus that attacks all green organs of the vine and, in particular, young growing berries. This attack produces a grayish dust. Grape destroyers fight this disease with sulfur spray. The roses, which are often seen at the edges of the vineyards, serve as "sentinels" because they first attack the disease, pointing to the winemaker which he must treat.
During the period of active ripening of the crop, the use of chemicals is unacceptable. A solution of potassium permanganate can be used as protection against disease. It is necessary to dissolve 5 g of the drug in 10 liters of water and treat the plant. It is impossible to cure grapes with this remedy, but it is quite possible to briefly stop the development of oidium.
Now it is difficult to create conditions that would be favorable for the development of vineyards. Changeable weather and improper care, together with contamination of the site, cause the development of diseases and increase the susceptibility of the vineyard to fungus.
Diseases associated with insects, mites, viruses or bacteria. Insects and mites: these are, for example, phylloxera, grasshopper, moth. Among the mites that attack the vine are mainly red and yellow spiders, which then cause foliar diseases or tufts.
Bundle Worms: The most famous ones are Eudemus and Cohilis, and they do significant damage. Viruses and bacteria: There are about forty viruses that attack the vine. They are usually transmitted by a transplant. Among the various grape diseases transmitted by viruses, the most common is short-circuited. In this case, the virus is transmitted from one plant to another by very small worms and causes a significant reduction in yield. The short-node vine must be torn off to remove all the roots and then rested for several years.
Oidium is a fungal disease of grapes
Oidium: what is it and how to deal with it
The prevalence of oidium is undeniable. The disease spreads to all areas, and no one is protected from its effects. It is also called powdery mildew. Oidium is a threat to all agricultural crops. Fungal spores concentrate on the green areas of the plant and spoil the taste of the vineyards.
Among the diseases transmitted by bacteria is luminescent dora, whose duty as a “chemical” cure has caused many organic winemakers to be rejected by the general public. Georges Siegenthaler and Jean-Marie Loriot. Clays are, in general, already used in agriculture for treating leaves, but their indication of use is not very clear and their effectiveness is low. Typically, hydrophilic clays are used, commonly known as aluminosilicate. Calcined kaolinite will have a preventive effect against botrytis and against the appearance of green leaf roller larvae!
It is more common in hot climates, when the temperature barrier crosses the border of thirty degrees. The fungus is able to overwinter in the internal parts of the plant and awaken at above-zero temperatures.
If the weather is humid and hot, then such climatic conditions are suitable for the development of fungus. All types of fungi develop in cloudy, hot weather, as well as in conditions of temperature changes. Rain stops the development of fungal spores due to the drip effect of the former on the grapes.
To prevent disease, choose grape varieties that are resistant to specific diseases. Timely fertilization of the site, weeding, and treatment of grapes helps to provide the plant with proper protection. When you clean grapes, do not leave plant debris on the site. Remove the weed and any infected vine debris from the area immediately.
Spots on the leaves are a sure sign of oidium
To determine whether grapes are infected with diseases, inspect the planting material. In the spring, spots will be visible on the formed leaves, as well as shoots yellow color., which over time will become covered with a gray coating on the upper section of the damaged element. At first, the spots have gaps, after which they combine into one continuous spot, and the leaves bend and bend at the edges. On the newly formed shoots, spots form under which brown marks form. If you try to remove stains, a specific smell may arise from the infected area. Over time, the planting material loses strength, the leaves and shoots of the plant dry out and die.
In the summer season, the planting material, its clusters and flowers begin to dry. Over time, the berries of the bunches are affected and spots form on them dark colors, as a result, the expected harvest bursts, dries and disappears.
As a result, the grapevine suffers losses in berries, and you don’t have to think about the harvest after being damaged by the fungus. The spores spread until they completely infect the planting material and deprive you of your harvest. The final result of the life activity of oidium is the death of all planting material. It’s not so offensive if the grapes were planted recently. But when you have been caring for the plant for many years, the losses will be quite noticeable. Therefore, be attentive to caring for the plant and control its development.
Berries affected by oidium burst and dry out
How best to treat a specific disease Sulfur can be used as a measure to combat fungal spores. It penetrates the spore and destroys it cellular level
, poisoning the fungus and preventing its further development. It is possible to treat for oidium in a preventive way
. That is, you should not wait until it manifests itself and affects the grape harvest. It is best to begin control measures after the vine begins to bud. The effectiveness of sulfur has an upper limit when the temperature rises above twenty degrees.
To avoid burns in the vineyard, it is necessary to treat the plant with sulfur in the morning and evening to avoid exposure of the plant to sunlight. For preventive purposes, use about forty grams per ten liters of water, in medicinal purposes
It is enough to use about one hundred grams for the same amount of water, the duration of treatment is two months. The choice of a sulfur-containing drug can be made by contacting a specialized store. The use of colloidal sulfur in the fight against oidium is popular.
Colloidal sulfur - a remedy against oidium A repeated control measure after the first spraying is carried out ten days later, the interval may be longer. The number of preventive measures during harvest ripening is six repetitions. There are also combination drugs
, which contain the required amount of sulfur in combination with other drugs.
Measures to combat oidium vary. Each gardener has invented his own method that suits him best. The main condition for prevention is to protect yourself from contact with the drug, since it is toxic and harmful to humans. Cannot be used chemicals
The drugs differ from each other, they can be different and used at certain periods of time. They come with instructions, so there won’t be any particular difficulties in caring for them. Depending on the climatic conditions, you can vary and choose between drugs that are acceptable for you and for this case oidium infection.
You can also purchase preparations that can be used when the berries ripen. Yes. The question is dubious, but their use is relevant, since they are not very toxic and do not affect taste qualities product. The harvested crop will need to be thoroughly washed under water to remove any remaining medicine from the bunches.
To save the harvest, the berries can be sprayed with non-toxic preparations during ripening
How to deal with oidium using improvised means
Just like it exists ethnoscience, are popular popular measures fight against fungi. There are many recipes, they were developed by experienced gardeners or scientists who know how fungal spores can be fought and what is necessary for this. To make your own medicine for oidium using available materials, you will need to do the following:
- Use a one hundred liter barrel and humus concentrate.
- Pour a third of the humus into the barrel, after sifting it.
- All this should be filled with warm water.
- Cover the top of the barrel with a thick cloth.
- Keep for six days in a warm room.
The material must be constantly mixed. Inside the barrel, the process of development of vital activity of microorganisms takes place. After this, the raw material must be filtered and poured into a spray bottle. IN for preventive purposes Newly formed leaves also need to be treated.
The fight should also be carried out in the morning or evening. This drug, prepared at home, gets inside the fungal spores and the microflora inside the preparation feeds on the oidium, destroying it. The suitable climate for processing is cloudy weather.
The fight is repeated seven days later, the third – just before flowering begins. This method of combating oidium is successful and confirmed by the experience of many gardeners. Depending on the degree of fungal damage to the plant, the frequency of treatment is adjusted. If the spores have not seriously affected the grapes, you can reduce the treatment to once or twice. But increased vital activity entails the need for several treatments.