Description of diseases of cucumber seedlings, control and treatment

Growing cucumbers in seedlings is not easy. At the initial stage of development, young seedlings are infected with pathogenic fungi, bacteria and viruses. Diseases of cucumber seedlings do not arise from scratch. They spread through the air, through infected seeds, soil. Early recognition of signs of pathology, timely treatment and prevention will help cucumber seedlings develop normally and produce high-quality fruits.

The main causes of pathologies

At the heart of any disease is non-compliance with the rules of vegetable farming:

1. The fungi that cause disease in cucumber seedlings lurk in the ground. If they take land from the garden, then most often it is infected. Commercial substrates are usually disinfected by manufacturers.
2. Self-collected seeds can carry microorganisms that cause diseases of cucumber seedlings.
3. For the development of pathogenic fungi, conditions such as excessive dry air, high humidity are favorable. And their combination with low temperatures will lead to wilting of seedlings.
4. Lack of nutrients occurs when cucumber seedlings have grown densely. Hence the seedling diseases. Fertilization should be done on schedule. It is impossible to saturate the soil too much with fertilizers, especially nitrogenous ones.
5. When the seedlings are watered with cold water, it suffers from this, gets sick.
6. Violations of growing conditions, when there is little light for the seedlings, and the temperature in the room is either low or high, lead to disease.

If the seedlings are grown in greenhouses, then it is necessary to control the illumination, temperature and humidity. Seedlings can also become infected when the soil and walls of the room are not disinfected.

Symptoms of fungal infections

Spores of fungi, having lived in the ground or seeds, begin to multiply actively, moving from one plant to the next. They penetrate into all parts of the seedlings, destroying young cucumber bushes. If spots appeared on the seedlings of cucumbers, then the fungi began their destructive activity.

To destroy diseases of cucumber seedlings, you need to know the most common signs.

Anthracnose

Although the seedlings of cucumbers are rarely affected by anthracnose, if they are already sick, then it is difficult to get rid of them. The leaves of the seedlings are covered with yellow or brown spots, as if burnt. Merging into one ulcer, the dead areas fall out, forming sclerotia.If diseased seedlings are not treated, then after planting them in open ground or a greenhouse, the disease will pass to the fruit, depriving the crop of vegetables.

The fight against fungal infection is carried out as follows:

• removing diseased plants;
• treating seedlings at the first signs of illness with a Bordeaux mixture or a solution of copper oxychloride;
• spraying with Fundazole.

Fungi are stored in the ground, therefore, before sowing cucumbers for seedlings, the soil is calcined in the oven.

Powdery mildew

Powdery mildew is recognized by the white bloom on the back of the leaf. On seedlings, the disease occurs when the seedlings have outgrown, they were not planted in the ground in time. From the leaves, whitish spots spread to the stems of the plant. The seedlings do not have enough moisture, their stems become thinner, and they themselves die.

The fight against the disease includes spraying with hot pepper infusion, baking soda solution, or Gamair-type preparations.

Downy mildew

Peronosporosis symptoms include the following:

• the appearance of light spots near leaf veins;
• distribution of large brownish spots;
• the presence of white bloom on the underside of the leaves, which becomes purple over time;
• curling and falling of foliage.

The course of the disease is rapid when the indoor air temperature reaches above 28 degrees, and the humidity is 90 percent.

To curb the development of the disease, treatment with a fungicidal agent Topaz or Fitosporin will help.

Fusarium wilting

Fusarium mold fungi will destroy young seedlings, if measures are not taken in time.

Cucumber seedlings look droopy during the day, recovering at night. The fungus penetrates the infected soil, forming a mycelium inside the plants.

So that the seedlings do not die, they are treated with Previkur. And it is better to destroy heavily affected seedlings.

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Gray and white rot

A slippery gray coating appears on the stems when the humidity reaches 90 percent. The reasons for the formation of white slimy deposits on leaves and stems are also the presence of a large amount of moisture both in the air and in the soil. If you notice the appearance of fluffy lumps on the seedlings, then, by stopping watering, spraying, you will bring the seedlings back to normal.

Root rot

It is impossible to see rot on the roots of seedlings. You can understand that the plant is sick by the following signs:

• thinning of the root collar;
• browning of leaves;
• stopping the growth of seedlings.

It is necessary to take measures to combat the disease immediately, otherwise the plant will die. It is best to transplant the seedling into another container, washing its roots, cleaning them from rot... Treating cucumber seedlings with fungicides will also help.

Blackleg

The activity of the fungus is manifested when the humidity in the room rises, and the seedlings have little light and the plantings are thickened.

The disease can be noticed by the black formations at the base of the stem of the seedlings. Young seedlings begin to sink to the ground and die.

If the cucumber disease has just begun, then its development can be prevented. Remove the soil from the affected stem and treat the soil around with a solution of copper sulfate (two teaspoons per liter of water). Dusting the stems with wood ash powder will also help. In advanced cases of the disease, nothing will save the diseased plant.

Ways to eliminate diseases

Diseased seedlings of cucumbers from diseases can always be saved. The main thing is not to waste time, but to start treatment, having discovered the first signs of pathology:

1. A diseased plant can be saved by transplanting. During the procedure, the affected leaves are removed by sprinkling the cut with crushed activated carbon. When the roots are damaged, they are washed, cutting off the black and rotten ones, treated in a weak solution of potassium permanganate. Seedlings are transplanted into separate containers, after disinfecting the ground.
2. Of the effective methods of treatment, treatment with Fitosporin or Topaz is popular.
3. Folk remedies cannot be discounted by fighting fungal diseases of cucumbers... You can use whey by dissolving one liter in a bucket of warm water.
4. You can also process seedlings with an infusion of onion peel, dissolving fifty grams of it in ten liters of water. The mixture is brought to a boil, and then cooled and filtered.
5. In seedlings treated with foliar dressing, the appearance of the leaves will be restored, the spots will disappear. For spraying, prepare a solution of ten grams of urea, two grams of copper sulfate and one gram of zinc sulfate per bucket of water.
6. For the recovery of the soil, the biological product Trichodermin is introduced into it.

Spraying and treatment of cucumbers is carried out in accordance with the signs of infection found in seedlings. A photo and a description of its symptoms will help determine the disease.

Review of the best fungicides

The market offers many chemicals for treating cucumbers against fungal infections. Diseases of cucumber seedlings can be treated with such drugs:

• Bordeaux mixture;
• Quadris;
• Topaz;
• Fitosporin.

Bordeaux liquid contains copper sulfate with lime, mixed with water. Lime mortar is used to neutralize the acidity of the liquid so as not to burn the leaves of the seedlings. Bordeaux mixture is used for spraying cucumber seedlings in order to prevent fungal diseases.

The components of the fungicide Quadris have a detrimental effect on the spores of the main pathogenic fungi, stopping the flow of air to them. After treatment with the drug, pathogenic microorganisms die within an hour.

The active substance in Topaz stops the development of mycelium, and the fungus dies. The product is well absorbed into the tissues of cucumber seedlings and acts instantly. For spraying seedlings, take one milliliter of the product for two liters of water. Topaz has a long-term effect on fungal spores. They carry out preventive treatment once during the period of seedling growth, then after planting cucumbers in the ground.

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Fitosporin is classified as a natural biofungicide, as it contains live spores and cells of bacteria that live in the soil. When in contact with water, they begin to multiply, suppressing microorganisms dangerous for seedlings. Dilute the powder with boiled or spring water. After a while, when the bacteria wake up and become active, they begin to spray the cucumbers. For better adhesion, you can add a little soap to the mixture. If the drug is liquid, then it is not necessary to dilute it.

These funds are used in the fight against fungal infections - powdery mildew, fusarium wilting, gray, white, root rot, anthracnose. Apply them according to the instructions at least three times. They help the seedlings regain health, protect them from infection later, after planting the seedlings in open or closed ground.

What viruses and bacteria infect seedlings

If fungal infections of seedlings are treatable, then it is more difficult, sometimes impossible, to get rid of viral and bacterial infections.

The viral mosaic is recognized by the spots chaotically scattered over the leaf blade. In shape, they resemble a mosaic composed of dark and light sections. At the same time, the ends of the young cucumber seedling leaves curl down, and the next ones do not develop.

Distinguish in cucumbers and a speckled green mosaic, when the surface of the leaves becomes wrinkled, covered with light spots. The disease occurs when the seedlings are planted densely, and the temperature in the room reaches above 27-30 degrees Celsius.

They carry the aphid mosaic virus, which often settles on cucumber seedlings.

The danger of a viral infection is that it destroys all seedlings. Therefore, it is necessary to destroy diseased plants quickly. And the soil from the containers is disposed of or disinfected.

Pathogenic bacteria cause angular leaf spot.For active development, microorganisms need a low indoor temperature and high humidity. And the ingress of moisture on the leaves of the seedlings will strengthen the action of bacteria. It is difficult to deal with them. Meanwhile, the leaves of the seedlings are covered with angular spots of different shades of brown. As the disease progresses, the plants die.

Getting rid of cucumbers from viral and bacterial diseases is impossible. It remains to say goodbye to sick seedlings in order to save the rest of the plants.

Preventive measures

You can prevent the development of diseases in cucumber seedlings by the following methods:

• disinfection of the soil before planting vegetable seeds;
• pre-treatment of seed material by soaking in a solution of potassium permanganate;
• adherence to the plan for planting seeds with a distance of three to five centimeters from each other;
• use of individual cups and peat tablets for seedlings;
• spraying cucumber seedlings with Bordeaux liquid.

Vegetable seedlings will be healthy if properly cared for:

1. Indoors, daylight hours should last at least twelve hours. Therefore, supplementary lighting of seedlings is organized using phytolamps or fluorescent lamps, hanging them at a distance of seven to ten centimeters from the seedlings.
2. Watering cucumbers is carried out regularly and only with warm water.
3. And you need to feed it taking into account the nutritional value of the soil in the pot. The introduction of only nitrogenous fertilizers contributes to the spread of diseases among cucumbers.
4. To reduce the dryness of the indoor air, you need to spray the cucumber leaves daily.

Competent organization of the care of cucumber seedlings leads to the fact that the plants will actively develop, grow and give good yields.

Biologicals in protecting seedlings from disease

Treatment with Trichodermin will help protect seedlings from diseases. The drug is used both for disinfection of seeds and for introduction into the soil during sowing. For one pot take twenty milliliters of biological agent. The seedlings are sprayed with a solution of the drug when they have two true leaves. The procedure is repeated every ten to twenty days.

The effect of the drug Planriz and Pentafag is high. Processing seedlings with means will reduce the risk of infection of cucumbers with fungal and bacterial infections.

An attentive attitude to vegetable plants, knowledge of the rules of agricultural technology contributes to the fact that young seedlings of cucumbers will delight with green leaves and a strong stem. Healthy seedlings will develop into robust plants that produce quality cucumbers.