Diseases of cucumber seedlings: description, treatment and fight against them + photo

Growing cucumber seedlings is not easy. At the initial stage of development, young seedlings are infected with pathogenic fungi, bacteria and viruses. Diseases of seedlings of cucumbers do not occur 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.

Main causes of pathologies

The basis of any disease is non-compliance with the rules of vegetable farming:

Fungi that cause disease in cucumber seedlings hide in the ground. If they take the land from the garden, then most often it is infected. Purchased substrates are usually disinfected by manufacturers.
Seeds collected by yourself may carry microorganisms that cause diseases in cucumber seedlings.
For the development of pathogenic fungi, conditions such as excessive dryness of air and high humidity are favorable. And their combination with low temperatures will lead to the withering of seedlings.
Nutritional deficiencies occur when cucumber seedlings have sprouted thickly. Hence the diseases of seedlings. Fertilizer application should take place according to the schedule. You can not saturate the soil too much with fertilizers, especially nitrogenous ones.
When seedlings are watered with cold water, they suffer from it, get sick.
Violations of growing conditions, when seedlings have little light, and the room temperature is either low or high, lead to diseases.

If seedlings are grown in greenhouses, then it is necessary to control the light, temperature and air humidity. Seedlings can become infected even 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 seedlings, destroying young cucumber bushes. If spots appeared on the seedlings of cucumbers, then the fungi began their destructive activity.

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

Anthracnose

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

The fight against fungal infection is carried out as follows:

removing diseased plants;
treating seedlings at the first sign of disease with Bordeaux mixture or copper oxychloride solution;
sprinkling with Fundazol.

Fungi persist in the ground, so 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 time in the ground.From the leaves, whitish spots extend to the stems of the plant. Seedlings lack moisture, their stems become thinner, and they themselves die.

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

Downy mildew

Symptoms of downy mildew include:

appearance of light spots near leaf veins;
spreading of large brownish spots;
the presence of white bloom on the underside of the leaves, which acquires a purple hue over time;
twisting and falling leaves.

The course of the disease is rapid when the temperature in the room reaches above 28 degrees and the humidity is 90 percent.

To curb the development of the disease, treatment with the fungicide Topaz or Fitosporin will help.

Fusarium wilt

Fusariosis molds will kill young seedlings if action is not taken in time.

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

To prevent the seedlings from dying, they are treated with Previkur. And it is better to destroy heavily affected seedlings.

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 coatings 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 seedlings, then by stopping watering, spraying, bring the seedlings back to normal.

Root rot

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

thinning of the root collar;
leaf browning;
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 of rot. The treatment of seedlings of cucumbers with fungicides will also help.

Black leg

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.

You can notice the disease by black formations at the base of the stem of seedlings. Young seedlings begin to lean toward the ground and die.

If the cucumber disease has just begun, then its development can be prevented. Rake the ground 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. With advanced cases of the disease, nothing will save the diseased plant.

Ways to eliminate diseases

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

You can save a diseased plant by transplanting.During the procedure, the affected leaves are removed by sprinkling the cut site with crushed activated charcoal. If the roots are damaged, they are washed, cut off black and covered with rot, treated in a weak solution of potassium permanganate. Seedlings are transplanted into separate containers, having disinfected the ground in advance.
From effective methods of treatment, treatment with Fitosporin or Topaz is popular.
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.
You can 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, then cooled and strained.
In the seedlings treated with foliar top dressing, the appearance of the leaves will be restored, the spots will disappear. For spraying, prepare a solution of ten grams of urea, two - copper sulfate and one gram of zinc sulfate per bucket of water.
To improve the soil, the biological product Trichodermin is introduced into it.

Spraying cucumbers and their treatment 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.

Overview of the best fungicides

The market offers many chemicals to treat fungal infections in cucumbers. Diseases of cucumber seedlings can be treated with such drugs:

Bordeaux blend;
Quadris;
Topaz;
Fitosporin.

In the composition of the Bordeaux liquid - copper sulphate 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 seedlings of cucumbers 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 per two liters of water. Topaz has a long-lasting effect on fungal spores. Preventive treatment is carried out once during the period of seedling growth, then after planting cucumbers in the ground.

Fitosporin is classified as a natural biofungicide, as it contains live spores and cells of bacteria living in the soil. When in contact with water, they begin to multiply, suppressing microorganisms dangerous to 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.

Use these funds in the fight against fungal infections - powdery mildew, Fusarium wilt, gray, white, root rot, anthracnose. Apply them according to the instructions at least three times. They help seedlings to regain he alth, protect against infection later, after planting seedlings in open or closed ground.

What viruses and bacteria infect seedlings

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

Viral mosaics are recognized by randomly scattered spots on the leaf plate. In shape, they resemble a mosaic made up of dark and light areas. At the same time, the ends of the young leaves of cucumber seedlings twist down, and the next ones do not develop.

There is also a speckled green mosaic in cucumbers, 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 air temperature in the room and high humidity. And the ingress of moisture on the leaves of seedlings will enhance the action of bacteria. It's hard to fight them. Meanwhile, the leaves of the seedlings are covered with angular spots of different shades of brown.Plants die as the disease progresses.

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

Prevention measures

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

disinfection of soil before planting vegetable seeds;
pretreatment of seed material by soaking in potassium permanganate solution;
compliance with the scheme of planting seeds with a distance of three to five centimeters from each other;
using individual cups and peat tablets for seedlings;
spraying seedlings of cucumbers with Bordeaux liquid.

Vegetable seedlings will be he althy if properly cared for:

Indoor daylight should last at least twelve hours. Therefore, they organize additional illumination of seedlings using phytolamps or fluorescent ones, hanging them at a distance of seven to ten centimeters from seedlings.
Water cucumbers regularly and only with warm water.
And it is necessary to feed taking into account the nutritional value of the soil in a pot. Applying only nitrogenous fertilizers contributes to the spread of diseases among cucumbers.
To reduce the dryness of indoor air, spray cucumber leaves daily.

Proper organization of care for seedlings of cucumbers leads to the fact that plants will actively develop, grow and produce good yields.

Biological preparations in the protection of seedlings from diseases

Processing with Trichodermin will help protect seedlings from diseases. The drug is used both for disinfection of seeds, and for incorporation into the soil during sowing. Twenty milliliters of a biological agent are taken per pot. Spray the seedlings with a solution of the drug when they have two true leaves. Repeat the procedure every ten to twenty days.

High effect from the drug Planriz and Pentafag. Treating seedlings with products will reduce the risk of infection of cucumbers with fungal and bacterial infections.

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, strong stems. He althy seedlings will develop into robust plants producing quality cucumbers.