Rusty spots on cucumber leaves: treatment, how to deal

You can not ignore the rusty spots on the leaves of cucumbers. A cheerfully green cucumber bed can turn into a sad sight in a few days - goodbye to the dream of crispy cucumbers. Brown or dark yellow spots that have appeared on the leaves may be traces of sunburn. Burns are a common phenomenon, but you should not be afraid of it. Burnt plants will move away and continue to grow further, you just need to carefully water the bushes without getting water on the leaves. The danger is a fungal infection that causes rust on cucumbers.

Why are there rust spots on cucumber leaves

Spores of various fungi are carried by the wind, accumulate on the leaves of weeds, live in the upper soil layer. A plant with strong immunity, with good care and a favorable microclimate, copes with the infection.

Different factors weaken cucumbers:

• cold weather;
• frequent rains;
• lack of sunlight;
• difference between night and day temperatures.

Infection (bacteria, fungus, virus) under adverse conditions causes diseases, the symptom of which is brown spots on the leaves.

Let's consider several common diseases in the open field and greenhouses: cladosporiosis, peronosporosis, anthracnose.

Diseases

Most of the plants infected with the fungus in the last stages of the disease are covered with dry, brown leaves. The first symptoms of almost all diseases look like white, yellow, brown spots on the leaves on cucumbers.

Let's consider only those diseases in which, due to rust on the leaves, the lashes die, lag behind in development, and cease to bear fruit.

Cladosporiasis

Otherwise, this disease is called brown olive spot. The fungus affects almost all parts of the plant:

• leaves;
• lashes;
• fruits.

At the initial stage, small red (olive) spots are visible on the leaves and stems. Over time, the spots darken, resemble a burn, gradually holes form in their place. Spores settle on the fruits, brown dents form on them.

Kladosporiosis usually affects cucumber lashes in August with sharp fluctuations in daily temperatures and during prolonged rains.

Experienced gardeners offer the following scheme of actions on how to get rid of emerging rusty spots:

1. The fungus grows better in a humid environment, so the first step is to stop watering the bushes. A pause in watering should last at least a week.
2. At an average daily temperature of 15 - 16 ° C, cover the cucumber ridge with spunbond or other covering material at night, remove the cover during the day.
3. Treat plants from the fungus.

Treat the bushes with one of the preparations:

• Bordeaux liquid, concentration 1%;
• copper oxychloride, 0.4% solution;
• "Oxyx" in the amount of 20 g per 10 l bucket, the water should be warm.

Peronosporosis

More often this disease of cucumbers is called downy mildew. Yellow spots form on the surface of the leaves, their size grows every day, the color of the spots changes from dark yellow to red. Leaves affected by the fungus wither, dry. Bushes may die.

How to deal with the problem? Having noticed signs of downy mildew, you need to temporarily abandon fertilizers and watering. Treat leaves and stems for fungal infection before it spreads to other plants. Treatment drugs:

• copper oxychloride;
• Bordeaux liquid;
• "Ridomil";
• Ordan.

In the open field cover the treated plants overnight with a film (covering cloth), in the greenhouse raise the night temperature to 16 °C.

Anthracnose

People call anthracnose verdigris. The appearance of rusty spots on the leaves signals the onset of the disease. Symptoms are recognizable - an anthracnose plant is easy to recognize:

• multiple brown spots on the leaves, which seem to be burned;
• dry leaves;
• brown ulcers on fruits.

The gardeners consider the main cause of the disease to be infected seed. The spread of anthracnose occurs when collecting seeds from diseased plants. The main factor leading to anthracnose is watering with cold water.

One treatment will not be enough. For the first time, to eliminate the causes, use Bordeaux liquid (1%). All damaged parts of the plant are regularly removed and sprayed with copper sulphate (0.5%). We save ourselves from anthracnose in different ways. It is acceptable to use homemade recipes for fungal diseases.

How to treat a diseased plant? It is better to prepare a working onion solution in an enameled or iron bucket. Hot water is needed for the infusion. For a 10 liter bucket of water, 2 tbsp. l. (50 g) chopped onion peel. Bring a bucket of water and onion peel to a boil and remove from heat.In a week, the working solution should be prepared. One bush of cucumber will take 1 liter of liquid fertilizer. If home control measures are ineffective, resort to the help of a fungicide.

Prevention

Knowing why rust appears on cucumbers, you can take measures to eliminate these prerequisites, we fight the fungus in advance. Start prevention from the first stage - sowing seeds. Protect seeds from fungus with a solution of manganese. Keep them in the pink solution for at least 15 minutes.

How to deal with the problem? Disinfect the planting substrate when propagating bushes in seedlings:

1. Method one - warm the soil for 25 minutes at 100 °C.
2. The second way is to spill boiling water.
3. The third way is to shed Phytosporin.

Further preventive measures concern the garden (greenhouse).In the garden, alternate crops. Do not plant crops in one place. Bad cucumber predecessors are zucchini and pumpkin, after which pathogens dangerous for cucumbers accumulate in the soil. Since autumn, we have been getting rid of the remnants of vegetables and weeds in the garden. 2 weeks before planting, we spill the beds with Fungicide or pink manganese solution.

Planting is processed during growth, flowering of the culture with Bordeaux liquid at least 4 times. We remove the leaves of cucumbers with rust, grease the cut with a solution of copper sulfate.

Crop loss from rust can be noticeable - up to 30%. But now we know what to do as soon as signs of pathology appear: we begin to urgently treat the diseased plant.

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