Cool and humid weather causes a lot of anxiety among summer residents, as this provokes the appearance of various fungal and viral diseases of cucumbers. Many are concerned about such a bacterial disease as powdery mildew, which is why it is important to know under what conditions it develops, what are the signs and how to deal with it.
What is powdery mildew?
Powdery mildew is a bacterial disease of cucumbers that provokes premature drying of plants. Leaves, stems, fruits may be affected. The disease is characterized by the fact that it spreads very quickly, which is why it is important to timely prevent and treat already affected plants.
Powdery mildew on cucumbers in a greenhouse often appears on plants that grow near doors, near poorly glazed frames, where it is damp and cool enough. In the open ground, such a disease often occurs with significant temperature fluctuations.
Powdery Mildew Conditions
Often mildew forms on cucumbers in the greenhouse, as there are the most suitable conditions for the occurrence of various diseases and the spread of bacteria. Especially if there have been cases of infection before. Often, even after a comprehensive treatment of plants and prophylaxis, bacteria remain in the soil and spring again form on the plants.
In the open ground, the disease occurs with the frequent change of dry days, wet and cool. The rapid spread of bacteria can provoke excessive introduction of nitrogen fertilizers into the soil.
Powdery Mildew Signs
The signs of powdery mildew on cucumbers are quite pronounced, and they allow you to exactly distinguish it from many other diseases. One of the first and most obvious signs is the formation on the leaves of a whitish plaque covered with drops of water. In addition, white plaque can affect many other parts of the plant located near the soil, and then the infection gradually spreads over the entire surface of the plant.
When conducting a more thorough examination, you can consider the presence of severe lesions and ulcers. Affected leaves cease to function normally. The plant begins to get very sick, dries up and gradually dies, since the fungus takes away all the required useful components from it.
Fruits affected by the bacterium become covered with cracks, where painful microorganisms penetrate, provoking the process of decay.
Powdery Mildew Control Methods
Many are interested in how to deal with powdery mildew on cucumbers and what methods, as well as drugs, are best used. It is very important to prevent the spread of the disease in the beginning. At the initial stage of fungus formation, plants can be saved. There are various methods of dealing with this type of fungal infection, in particular, such as:
- prophylaxis;
- the use of folk remedies;
- chemical treatment.
When choosing treatment methods, the infection period is of great importance. At the initial stage, prophylaxis is required. With a slight defeat of the plant, folk methods are used, and with an extensive - chemical preparations. If the fruits are already beginning to ripen, then the use of chemicals is unacceptable.
The use of chemicals
When the very first signs of a fungal infection of a plant occur, it is important to know how to deal with powdery mildew on cucumbers. It is worth remembering that measures to eliminate bacteria must be taken immediately, otherwise it will be very difficult to destroy the harmful fungus. Before carrying out therapeutic measures, you need to stop feeding, and it is also important to thin out plantings, remove dry plants, and cut off affected peduncles.
To combat this type of bacteria, fungicide preparations, in particular, such as:
- means "Fundazole";
- mix "Topaz";
- Tilt spray liquid.
The Fitosporin preparation against powdery mildew on cucumbers is well established. To treat plants with this tool, you need to dilute 6-10 g of the drug in 10 l of water. Among its shortcomings, one can single out the fact that it tolerates sunlight very poorly. However, it belongs to biofungicides, therefore it is safe for people and animals.
Asking the question of how to treat cucumbers from powdery mildew, the Bactofit remedy can be used. This is a very good biofungicide that can be used to spray plants and water them under the root. To prepare the product, you need to take 20 ml of the drug and dissolve it in 10 l of water. The only drawback of such a tool is that it is washed off by precipitation or water during irrigation.
When using the drug "Topaz" you need to take 3 g of the product and dissolve it in 10 l of water. It is worth remembering that this fungicide is forbidden to be used throughout the entire period of fruiting, in addition, you must observe safety precautions when working with this tool.
A good result is shown by the HOM tool. To use it, you need to dilute 40 g of powder in 10 liters of water. Spray the resulting solution on the beds with cucumbers. This amount of solution is enough to process 10 square meters. meters of garden area.
The frequency of treatment with these and other drugs is 1 time every 2 weeks. Chemicals prevent the formation of spores of the causative agent of the disease, and high air temperature enhances their effect. Chemicals show a protective effect literally a few minutes after spraying and remain for 2 weeks after treatment. Despite the fact that the treatment with biofungicides is allowed during the fruiting period, however, it is possible to consume vegetables as food after the treatment no earlier than in 2-3 days.
It is worth remembering that some means can be dangerous to humans, so it is important to follow certain safety measures. It is very important to know how to deal with powdery mildew on cucumbers correctly, since this fungus develops resistance to chemicals over time, therefore, during processing, they must be periodically changed.
The use of folk techniques
Folk remedies for powdery mildew on cucumbers help prevent the spread of the disease at the very beginning of its occurrence. A good result can be obtained by using such means as:
- soda solution;
- copper sulfate;
- horsetail decoction;
- mullein solution;
- soap solution.
You can use folk remedies both for the treatment of infected plants, and as a prophylaxis. When conducting prophylaxis, plants need to be sprayed after each rain.
The use of baking soda
Baking soda from powdery mildew on cucumbers helps a lot, it has been widely used for many years, it is quite simple to prepare such a solution. To prepare the product, you need to take in equal proportions liquid soap and baking soda, 1 tsp each, and then pour all this with 5 l of boiling water. Mix well, cool. Spray cucumbers with such a solution 1 time every 10 days. The total number of treatments largely depends on the degree of damage to the plants. It is best to use not ordinary soap, but tar, since it helps to more effectively remove fungal infection.
Use of copper sulfate
Folk remedies for powdery mildew on cucumbers suggest the use of copper sulfate. You need to take 5 g of copper sulfate, mix it with 50 g of soap and pour 5 liters of water. Such a tool helps prevent the development of spores and treats an existing disease.
Mullein and whey solution
Selecting means of controlling powdery mildew on cucumbers, you can use a solution of mullein. To prepare it, you need to dissolve 1 kg of fertilizer in 10 liters of water, and add 1 liter of water before use.
Milk whey helps to cope with the fungus. To do this, you need to dilute it with water and conduct a root treatment of cucumbers with this solution. After that, a film of milk bacteria is formed on the leaves, which prevents the growth of the fungus.
Decoctions of plants
A decoction of horsetail helps to cope with the fungus. To do this, take 100 g of fresh or dried plants, pour 100 g of water per day, then boil for 1-2 hours, strain, cool, dilute it with water in a ratio of 1: 5 and spray cucumbers. You can store such a decoction for a week.
A good helper against fungus is considered an infusion of weeds. To do this, half a bucket of grass must be filled with water and insisted for several days in a warm place.
You can also use a nettle broth, which helps to quickly and efficiently deal with bacterial spores.
Garlic
Asking the question of how to treat cucumbers from powdery mildew, you can apply the infusion of garlic. To do this, insist on a medium-sized head of garlic in water for a week at room temperature. Strain the resulting infusion, dilute 10 liters of water and spray onto the plants using a spray bottle.
Other Mildew Means
It helps to cope with the defeat of bacteria by pollination of sulfur leaves. To do this, carefully crushed sulfur should be poured into gauze and pollinated in warm sunny weather. After processing, cucumbers in the garden need to cover with a film for 2 hours. When processing in a greenhouse, you need to close all windows and doors.
A good result can be obtained by spraying cucumbers from powdery mildew with a solution of potassium permanganate. To prepare it, you need to dilute 1.5 g of potassium permanganate in 10 l of water.
An effective means is also the spraying with colloidal sulfur, which must be diluted at the rate of 40 g per 10 liters of water. Processing with such a tool is best done in cloudy weather.
Prophylaxis
You need to know not only how to deal with powdery mildew on cucumbers, but also how to prevent its occurrence on plants. Among the main preventive measures, it is necessary to highlight such as:
- planting varieties of cucumbers resistant to powdery mildew;
- pre-sowing seed treatment;
- watering with warm, settled water;
- careful use of nitrogen top dressing;
- careful collection and destruction of plant debris.
These reliable preventive measures will prevent subsequent exposure to powdery mildew. In addition, it is necessary to provide the plants with a sufficient influx of fresh air, which is why it is necessary to thin out seedlings in a timely manner, as well as remove old leaves in contact with the soil.
Watering cucumbers is necessary only after the complete drying of the top layer of soil. Watering and spraying should be done in the morning, so that the plants have time to completely dry before evening.