Causes, symptoms and treatment of anthracnose in cucumbers
Often, marble spots appear on the foliage, stems and fruits of cucumbers, destroying plant cells. The disease that causes this reaction is called cucumber anthracnose or copperhead. Consider the causes, symptoms and treatment of the disease.
The reasons
The disease is caused by the pathogenic fungus Colletotrichum. It gets through infected plant debris on the ground, often transferred from one bush to another by wind or rain. Also, seeds collected from diseased fruits become a source of infection. Crops located both in the open area and in the greenhouse are susceptible to infection.
This is a dangerous infection, because not only cucumbers are sick with it, but also other vegetables in the garden - grapes, peas, melon, pumpkin, zucchini, beans and bushes of raspberries, currants and gooseberries.
Greenhouses with a high moisture content provide comfortable conditions for fungus growth. Carriers of fungal spores.
- wind;
- prolonged wet weather;
- insects;
- a tool used on the affected area.
Conditions for the development of the disease
Wet and warm weather is a comfortable environment for the development of fungal infections. It spreads with dew and frequent heavy rains. The growth of the fungus is activated when the air humidity is above 60 degrees.
Greenhouses with a high moisture content provide a comfortable environment for fungus growth.
The incubation period for spore growth reaches 6-7 days; at elevated air temperatures, it is halved.
Aphids and spider mites are carriers of spores from sick bushes to healthy ones, so you should fight these insects.
Planting density is also the reason for the transfer of spores from a diseased plant to a healthy one.
Under suitable conditions, the fungus multiplies rapidly, leading to disease all plants growing in the garden. But when the air humidity drops sharply, the growth of infection slows down and stops.
Symptoms
Fungal disease in wet conditions affects the stems of the shoots, brown spots attack the necks of the roots. The fungus develops rapidly - the stem breaks, the seedling dies. On adult cucumbers, the fungus is capable of infecting all parts - the root, stem, leaves and fruits. With the development of the disease on young shoots, they die.
Also, the reason for this phenomenon is non-compliance with the temperature and water regime. In adult cultures, the symptoms are as follows.
- Several brown spots appear on the bottom of the bush.
- The spots grow and merge, the leaf dries up, the stem turns black.
- After damage to the leaves, the fungus passes to the fruit.
- In dry weather, the site of infection dries up.
- When wet it starts to rot.
At the initial stage of development, leaves and stems are covered with copper-brown spots with a diameter of several millimeters to 4 centimeters. The spots are concentrated at the edges of the leaves and between the veins. First, one leaf below is infected, and then the infection spreads to the entire plant. Therefore, it is difficult to recognize the disease at the initial stage of development.
At the second stage, the leaves turn yellow, the diameter of the spots increases, and they merge with each other. As a result, the leaves lose their photosynthetic function, and the affected stems often break. It is necessary to treat vegetable crops when the first symptoms of infection are detected.
The stains darken and dry out over time. On the stems, the foci are pressed inward by a few millimeters. The infection that has passed on to the fruit also forms depressed areas, the young vegetable begins to rot.
At high humidity, the spots become covered with a fungal pink bloom. These are spores that multiply on the bush under wet conditions.
The infected fruit becomes bitter and unusable.
Cucumber treatment
In case of a cucumber disease, treatment begins immediately. The following drugs are used to combat: solutions containing sulfur, Bordeaux mixture, Quadris drug. These medications kill the spores of the fungus by stopping the spread of the infection. They begin to use these funds at the first symptoms of the disease, with extensive distribution they are not very effective.
Fungicides used to treat anthracnose.
- Topaz.
- Fitosporin.
- Previkur.
- Abiga Peak.
- Quadris.
- Poliram.
- Cumulus.
- Copper oxychloride.
- Tiovit Jet.
Treatment is carried out in protective clothing and a mask, after the procedure, hands are thoroughly washed in soapy water.
The root form of the disease is treated as follows: 1% Bordeaux mixture or 5% Abigo Peak. They are shed mainly at the root after abundant watering of plants with warm water. Only a small part of the mixture should get onto the cucumber stalks. Consumption - up to 1 liter per plant. The treatment can be repeated 2-3 times a week. Folk remedies, this disease is rarely treated.
Prevention plays an important role in preventing plant infection.
Prevention
Before planting, the purchased seeds are soaked in a solution of potassium permanganate. Also, positive results were obtained by soaking the seeds in Pseudomonas mycophaga, a bacterial culture liquid isolated from the rhizosphere of pumpkin crops.
Seed dressing is carried out using the following chemicals.
- Imvunnocytophyte.
- Tiram.
- Treater TMTD.
In addition to seed treatment, soil is disinfected before planting. The applied fertilizers have a negative effect on the spread of the fungus. After planting, seedlings are examined daily for symptoms of fungus. When an infected plant is found, it is removed.
When growing plants in film greenhouses, they monitor the accumulation of moisture on the film. With a large amount, it is shaken off, the greenhouse is ventilated. Plants thinned and planted at a sufficient distance from each other will inhibit the spread of bacteria. Removing old plants from the surface of the garden will also reduce the chance of infection.
Anthracnose appears not only on cucumbers, but also affects other vegetable crops grown on the site. At the same time, the yield of plants is reduced by 50%. Therefore, it is important to prevent all diseases, and if an ailment is detected, immediately start treating it. Subject to the growing conditions, cucumbers will delight their owners with a plentiful and healthy harvest.
