Onion diseases: description and treatment, control measures and what to do with photos

So that onion diseases do not cause significant damage to the crop, you need to know preventive measures, the rules of cultivation and care, as well as ways and means of dealing with them. Knowing the description of onion diseases, you can also carry out the correct treatment.

Onion neck rot

The causative agent of cervical rot is a fungal infection. Often the disease affects immature bulbs or crops that have been in moist soil for a long time.

A characteristic feature is the softening of the neck of the bulb, its thinning and decay. A gray fluffy coating and an unpleasant odor appear.Gradually, the plaque turns into small black grains that merge with each other. If you do not start the fight against the disease, plaque covers the entire bulb.

If you plant infected bulbs, then in the future the feathers grow weak, pale green. Inflorescences do not reach the ripening stage, become moldy and lower their heads down.

The main agrotechnical measures to combat the disease are:

• For planting, you need to choose fungus-resistant varieties;
• after harvesting, the site is cleared of all waste;
• weeding, watering the beds is carried out carefully, without damaging the feathers;
• don't overdo it with nitrogen fertilizers;
• you need to harvest in dry weather, drying the harvested bulbs for at least two weeks;
• the leaves of the harvested onion should not be cut too short, it is recommended to leave a stump of 3-4 cm.
• only whole, large and dense heads are selected for storage, without damage;
• planting material should preferably be treated with special solutions.

If cervical onion rot has already appeared, chemical control measures will help. Treatment with fungicides such as Tigam, Benlat, Fundazol helps. During the formation of heads, the beds are watered using the drug Effecton. For foliar treatment, you can use a solution of copper sulfate or Bordeaux liquid.

Downy mildew

Fungal disease downy mildew favorably spreads after prolonged rains or when watering rules are not followed. Affected vegetable feathers look lethargic, drooping, lose their color saturation. Gradually, the leaves become covered with brown-yellow spots, dry out and the plant dies.

Onion pests such as aphids and whiteflies contribute to the spread of the infection. They spread the spores to he althy plants, and the disease quickly picks up.

Preventive measures against the disease are:

• vegetable beds need to be weeded;
• even in the autumn they begin to prepare the land allotted for planting onions: they dig up, fertilize, disinfect;
• seedlings can be sprayed with a solution of Bordeaux mixture;
• in a rainy, cool summer, it is useful to treat vegetable beds with biological products such as Fitosporin, Planriz, Gamair.

To disinfect the soil, you can use a solution of copper sulfate, Fitosporin, Alirin, Gamair, Baikal-Em. You can treat the onion from powdery mildew that has appeared with such means as Thanos, Ridomil, Vectra, Topaz.

Onion rust

Signs of fungal rust damage are wilting, drying and yellowing of the leaves.The bulb is formed small and stored poorly. Tubercles of orange-yellow or brown-reddish color appear on the leaves affected by the disease. Gradually, the feathers begin to die off.

Spores of a fungal infection tolerate cold well and hibernate on plant debris. That is why it is recommended to remove the remaining tops from the garden at the end of the growing season. Cool, rainy summers, too dense plantings and an excess of nitrogen in the soil also contribute to the development of rust.

What to do if the feathers are covered with bloom and there are other signs of rust? Most often, the disease develops at the end of summer, so it is important to inspect your plantings daily. In the event of a problem, you need to stop watering the beds and applying nitrogenous fertilizers. Damaged stems are cut and removed away from the site.

If signs of disease were found, the vegetable crop should be treated with fungicides. Folicur, Ordan, Topaz are considered effective. The drug Hom, Tilt or simple Furacilin copes well with the disease.

Fusariosis

Fusariosis is a common onion disease. The appearance of the first signs is indicated by yellowing and wilting of the leaves. Initially, the tops of the feathers are affected, gradually rotting spreads to the entire length of the leaves. Often the bulb itself rots. It becomes watery, softens and smells unpleasant. A pinkish fungal coating forms on the bottom of the bulb.

Provoking factors are excess moisture in the soil, untimely harvesting, poor-quality planting material, too dense planting.

Proper soil and seed preparation is considered preventive control measures. It is recommended to treat the soil with copper sulfate or a preparation such as Iprodion. Disinfection of planting material is carried out with a solution of the drug Fitosporin, Quadris or Fundazol, it can be soaked in a weak solution of potassium permanganate.

If signs of illness are found, it is necessary to remove the affected plants from the garden and burn them, and treat the remaining vegetables, for example, with Fitosporin.

Bacterial onion rot

Bacterial rot penetrates the wounds that form on the leaves during weeding or watering. The first signs of a rot infection become noticeable on the leaves. Light spots first appear on them, then they increase in size and reach the neck. After rains, watering or dew, bacteria penetrate deep into the soil to the onion head.

Unlike bulbs that are affected by onion bottom rot (fusarium), heads with this disease may look he althy in appearance. But when cut, you can see that the core is completely rotten. Gradually, decay spreads from the center to the edges of the head.

Prevention and control of the disease is to observe the following rules:

• it is not recommended to plant onions in the same place for several years in a row;
• after harvesting from the garden, you need to remove all plant debris;
• all work in the garden should be carried out carefully, without injuring the onion feathers;
• monitor the regularity of watering, from the moment the bulb is formed, they should be moderate;
• loosening the soil slows down the spread of the disease;
• fertilize in accordance with the norms (an excess of nitrogen causes infection activity).

Carriers of infection are pests such as onion fly, spider mite. Therefore, preventive measures should also be aimed at pest control.

So that bacterial rot does not appear in the planting material, it is kept for several hours in a solution of formalin or potassium permanganate. Then dry well in the sun. Suspicious bulbs are treated with antibiotics. Suitable mixture of tetracycline with streptomycin.

Green mold rot

Green moldy rot affects already harvested crops at the storage stage. The onion shell dries out, becomes covered with green mold. The main reasons are: damage to the bulbs during harvest and high humidity in the room where the crop is stored (more than 70%).

Often onion pests become the cause of the development of the disease. They still infect the plant in the beds, and under favorable conditions, pathogens begin to actively develop, leading to rotting of the crop.

Water brownish spots appear on the infected bulbs near the bottom. After a while, an unpleasant smell of mold appears from them, and a greenish coating is observed under the scales.

Measures of prevention are thorough drying of the crop and compliance with all requirements for its storage. The room should be dark, cool (about +3 degrees) and not damp. Pre-disinfection of the place for storing onions.

It is recommended to select bulbs in advance for planting next year. Tip: remove the seed material for storage in another place. Review it periodically and get rid of diseased and damaged bulbs in time.

Black mold rot

Fungal disease black mold rot is a problem mainly of already harvested crops that have been put away for storage. Sick bulbs become soft, rot, deform, the scales dry out and become covered with a black coating. But you can see the signs in the garden. The spores of the fungus infect the leaves when they are wet for more than 7 hours.

The development of the disease is provoked by improper storage conditions. Black mold on onions develops in musty, damp rooms where there is high humidity, large temperature fluctuations and poor air ventilation.Provokes the disease is not well dried crop after digging out of the soil.

Protection measures are:

• while loosening and weeding the soil, care must be taken not to damage the leaves, otherwise the wound can become a site of infection;
• should protect and harvested crops from damage;
• indoors maintain low air humidity and low temperature;
• remove old tops of plants from the garden;
• since onion pests cause disease, they should not be allowed to appear in the garden.

Harvesting must be done in a timely manner. Do not remove unripe or overripe onions. It will be poorly stored and a high risk of developing various diseases.

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