When growing cucumbers in a protected ground, a variety of diseases can develop. Not only long-term crop cultivation in the same greenhouse leads to them, but also improper disinfection, lack of fertilizers. To know how to treat cucumbers from diseases in a greenhouse, you must be able to determine the cause of the disease. To do this, you do not need to do any analysis: it is enough to know the signs of the disease and what drugs to treat.
Aphid
Melon aphids parasitize on the inside of leaves, on flowers, ovaries. It can cause wrinkling and curling of the fruit. Typically, cucumbers are damaged by this pest in the second part of the summer. The pest is developing rapidly.
At the beginning of this disease of cucumbers in the greenhouse, the leaves acquire a yellowish tint. In a few days, the aphid breeds to such an extent that it can damage not only foliage, but also flowers and fruits.
To get rid of aphids, it is necessary to timely weed the weeds on the site, to process trees, shrubs, to destroy garden ants.
You can get rid of the disease of cucumbers in the greenhouse with the help of folk remedies or by treating the plants with special preparations for aphids.
Among folk remedies, tincture of red pepper has proven itself well. For its preparation, thirty grams of capsicum, a glass of tobacco are taken. Everything is steamed in a bucket of boiling water and infused for a day. After the infusion is filtered, a spoon of green soap and a glass of wood ash are added to it. The consumption of the drug is a liter per square meter. Spray with pepper tincture every day for a week.
Some summer residents fight aphids with a solution of soap and ash. To prepare it, you need to dissolve two glasses of ash in a bucket of water and add a spoonful of soap. The composition is left for a day. Before use, the product is filtered. Spraying is carried out every day for ten days.
Chemicals can help get rid of cucumber disease in a greenhouse faster. From aphids, you can use "Karbofos", "Fufanon", "Aktar", "Arrow" or other means available in the garden store. It is necessary to use any drugs according to the instructions attached to them.
Whitefly
Pests and diseases of cucumbers in the greenhouse can completely destroy the crop. One of the pests that feed on plant sap is the greenhouse whitefly. It is not always possible to detect it on a plant, but sticky white traces, blackening of leaves and their drying indicate its presence.
Whitefly can enter the greenhouse not only from weeds growing next to it, but also from neighboring sites. The pest flies through the door, vents, sits on the plant and multiplies rapidly, destroying vegetables.
It is difficult to deal with whiteflies, it is easier to carry out preventive measures. To this end, the vents are covered with gauze, folded in several layers. In the greenhouse itself, pieces of plywood are painted, painted yellow and smeared with rosin with honey or petroleum jelly. Such traps attract whiteflies: insects fly to the bait, stick to the board and die.
Be sure to loosen the earth to a depth of at least three centimeters, make humus or peat.
Powdery mildew
The diseases of cucumbers presented in the photo in the greenhouse can not always be true. Powdery mildew is an ailment that can be of two types: true and false. Both that, and another is a disease, but each of them has its own characteristics and different treatment methods.
Downy mildew affects the plant at different stages of growth. It occurs both in open ground and in the greenhouse. Moreover, the infection persists in one place for up to six years.
Signs of the disease are the presence of oily spots of a green tint. Over the course of two weeks, they increase in size, becoming brown, as if the plant received a burn. Then the sheet dries quickly, in just a couple of days. This phenomenon is said to have "sour rain." In fact, the disease occurs with sharp changes in day and night temperatures, for example, during the day +25, and at night +10. Downy mildew can occur when watering with cold water.
Diseases of cucumbers in the greenhouse and their treatment affect the quantity and quality of the crop. To cope with powdery mildew, it is necessary to stop watering for a week, ventilate the greenhouse. As soon as the humidity level decreases, the plants are treated with special preparations, such as Topaz, Oksihoma. Dilute funds according to the instructions.
During the processing of the greenhouse, it is important to spray not only the plants themselves, but also the greenhouse, the soil under the cucumbers. After processing, the greenhouse is aired.
True or powdery mildew is manifested by the formation of white plaque on leaflets. The disease spreads quickly, the sheets look as if they were sprinkled with flour. Then the plants dry.
The disease occurs due to irrigation with cold water, with a sharp temperature difference. Cucumbers can infect weeds, insects that have visited a diseased flower and flew into the greenhouse.
At the first signs of cucumber disease in the greenhouse, their treatment and prevention of powdery mildew is carried out by the following means:
- Mullein solution. For him, you need to take a bucket of warm water and a liter of liquid mullein.
- A tablespoon of urea.
- Everything is thoroughly mixed. The solution is treated with plants in warm weather. Leaves are sprayed from below and from above.
You can use sulfur for pollination of plants. To do this, take sulfur and put it in a bag. In warm weather, sulfur is scattered throughout the plants.
There are special preparations for powdery mildew, for example, "Topaz", "Barrier" and others.
Brown olive spotting or cladosporiosis
You can see on the Internet a lot of photos of cucumber diseases in the greenhouse, in which the stems and fruits are covered with rounded sores of olive color. They literally turn brown before our eyes, grow. Grooves appear on the leaves, which dry out, destroying the leaf blade. This disease - cladosporiosis - a fungal infection.
The disease occurs in cool weather with sudden changes in temperature. In hot summers, olive spotting can occur at the end of the growing season. The infection spreads with rain, wind, water. The fungus remains on the plant and in the soil for a long time.
To prevent the disease, it is necessary to observe crop rotation and not to return the cucumbers to their original place for four years. It is also important to ventilate the greenhouse, remove all plant debris from the beds in time, and not water the plants with cold water.
At the first sign of cladosporiosis, watering should be stopped for five days. If the average daily temperature drops below eighteen degrees, you need to raise it to at least twenty degrees.
Be sure to carry out the treatment of plants with one percent percentage of Bordeaux liquid, copper chloroxide, Oskikhom.
White rot or sclerotinia
The fight against cucumber diseases in the greenhouse comes down not only to airing and monitoring the temperature, but also to timely processing of plants. This helps to get rid of a variety of viral, fungal infections. One of the most dangerous ailments is white rot. With this disease, the fruits, stems, leaves are covered with a solid white coating. The disease can be confused with powdery mildew, but its difference is that the fruits are involved in the process - they become white.
Sclerotinia is manifested due to fungi wintering in the soil and rapidly spreading on the ground with humid air.
Proper treatment for cucumber disease in the greenhouse and preventative measures will help save the crop. To get rid of white rot, it is necessary to remove all diseased parts of the plant by sprinkling them with charcoal or lime. If the fungus has spread greatly, then you need to remove the entire plant.
Then the bushes are fed a nutrient solution, taking ten grams of urea, one gram of copper sulfate and sulfur sulfate. All this is bred in a bucket of water. The solution is watered with cucumbers.
Gray rot
When gray rot stems, leaves and flowers, covered with brown, blurry watery spots. They quickly merge with each other, becoming covered with a grayish coating. This ailment refers to bacterial, capable of affecting all parts of the plant.
The main cause of cucumber disease is waterlogging and low temperatures. This type of disease can be prevented. To do this, do not thicken the plantings, as well as observe the rules of crop rotation. From the greenhouses where cucumbers were grown, it is necessary to remove all plant residues, as well as to process the greenhouse itself and treat the plants on time for preventive purposes.
If suddenly the disease manifests itself, it is necessary to treat the plants with fungicide. It can be Rovral, Bayleton, Home. All affected parts of the plant are removed.
Root rot
Diseases and pests of cucumbers in greenhouses are able to persist for many years in the ground. Bacteria, viruses, pest larvae, fungi winter well in the soil, and when favorable conditions are created, they are activated, destroying plants.
When root rot leaves begin to fade, gradually they dry. If you pull out a bush and look at its roots, you can see that they are painted in red color, look rotten. These signs indicate root rot - the most dangerous and common disease.
As soon as the disease is discovered, the first thing to do is to stimulate the formation of new roots. To do this, around the bush, you need to raise the ground level by at least five centimeters. This option will allow the cucumbers to start up new roots. You can trim the leaves from the bottom and lay the ring with a whip. After a week, the bush will be re-established. During this procedure, the bush is not watered under the root and only with warm water.
If the plant has already died, then it is removed from the greenhouse with soil. Fresh soil is poured into the formed hole. The entire tool is processed.
Anthracnose
Timely treatment of cucumbers from diseases in the greenhouse is able to save the bushes from coppers or anthracnose. This disease manifests itself on leaves, stems with brown spots. Leaf blades begin to dry out, the fruits become covered with wet sores.
The cause of the ailment is often infected seeds collected from diseased plants. Also, a fungus that persists in the upper layer of soil in plant debris can lead to the disease. When watering with cold water, sudden changes in temperature contribute to the rapid spread of the disease in the greenhouse.
So that the disease does not occur, it is necessary to observe crop rotation, as well as to remove the remains of plants from the beds in time, to carry out tillage.
If the plant suddenly became ill, it is necessary to treat with a Bordeaux mixture (1%). All affected parts of the plant are removed, sprinkled with lime.
Lack and excess of nitrogen
To get a good harvest, it is important not only to know and see the manifestation of the ailment. After examining the cucumber disease in the photo, treatment in the greenhouse will help protect the crop from death.
One of the most common plant problems is yellowing of leaves. Each type of micronutrient has its own signs of yellowing. If the top sheet changes color, this indicates a lack of nitrogen. Such plants form small fruits in small quantities. Plants are poorly developed.
When oversaturated with nitrogen, the leaves acquire a dark green hue. Old and middle leaves bend, merge into a single whole, a brownish tint appears. The fruits are smaller, nitrates accumulate in them. Huge doses of nitrogen can kill the plant in a matter of days.
To solve the problem with a lack of nitrogen is simple. To do this, the bushes are watered with infusion of mullein or use a solution of nitrate (a tablespoon in a bucket of water).
If there is an excess of nitrogen, it must be washed out of the soil. For this, abundant watering is carried out every day, and before sunset, foliar fertilizing is carried out with two percent calcium nitrate.
Calcium
For proper growth of cucumbers, calcium is needed. With its excess, the bush becomes fragile, stiff. With a lack of leaves, light streaks appear. Over time, they expand, causing leaf wilting and their death. On inflorescences rot is observed. It applies to fruits, stems, roots.
To cope with the problem, it is necessary to fertilize with calcium.
Phosphorus
With a lack of phosphorus on the leaves, yellowness occurs, necrotic spots form, and then the leaves fall. The plant begins to age quickly, the absorption of potassium is disrupted.
With a deficiency, the plant stops growing, the ovaries and flowers fall. To solve this problem, it is necessary to water the plants with phosphorus-potassium fertilizer. It is bred according to the instructions.
Iron
On young leaves, you can see a lack of iron. It is manifested by clarification of the top of the cucumber. On the leaf blades, the veins become whitish, growth and flowering slow down. To eliminate this cause of plant death, it is necessary to add a complex fertilizer solution under the root. It can be vermicompost or mullein infusion.
Manganese
Plants need manganese to synthesize chlorophyll. He takes part in a number of oxidative processes occurring in the cucumber.
With an excess of manganese, the soil begins to sour. This leads to a decrease in the concentration of chlorophyll, chlorosis begins between the veins on old leaves, then on new ones. Leaf blades are covered with brown necrotic spots.
With a lack of manganese on the sheet, bright dot spots form on the upper part. To solve the problem of manganese deficiency, it is necessary to fertilize with a solution of manganese (0.3 mg per liter of water), or with a solution of complex fertilizer, for example, biohumus.
There are other types of micronutrient deficiencies, manifested by a change in leaf color, a change in the shape and size of the fruit, falling inflorescences and other manifestations. To avoid them, it is important to feed the plants with complex fertilizers once every two weeks.
To reduce the likelihood of disease, plant disease-resistant cucumber varieties in greenhouses. Such plants are less likely to get sick, give a high yield.
Disease-resistant cucumbers in greenhouses rarely suffer from rot, powdery mildew and other ailments. In order to get a good harvest from them, it is necessary to carry out timely dressing and monitor the microclimate in the greenhouse.