Diseases and pests of onions and their control

Diseases and pests of onions and their control

Onion crops are distinguished by good germination and rapid growth. However, the harvest may decline or even die due to diseases and pests. Timely prevention and adherence to the landing technology significantly reduce the risks. In this article, we will analyze the main questions of most gardeners: why the tips of feathers on onions can turn yellow, what pests can ruin the harvest in spring or autumn. And also what to do and how to deal with adversity.

The main diseases of onions and the fight against them by different means

Planting and growing onions in a small area or on a huge plantation is not difficultif you adhere to the technological process. However, in addition to the planned activities, it may be necessary to treat the crop from pests and insects. You should not ignore the signs of plant damage, because in just a few days the beds can significantly thin out. And it is quite difficult to cope with a neglected form of the disease or the mass colonization of insects, one cannot do without the use of chemistry. Therefore, it is recommended to include preventive procedures in the onion care schedule in order to prevent serious problems.

Downy mildew

Peronosporosis is one of the varieties of fungal infection, the pathogen is perfectly preserved on onion husks, seeds. The transition of bacteria to the active phase occurs when favorable conditions are created, which are characterized by high humidity and a positive temperature regime. The disease can be recognized by the following signs:

  • the formation of yellowish-green oily spots on the surface of the leaves;
  • a gray-purple bloom settles under the feathers;
  • an increase in the parameters of spots;
  • dying off of sheets.

The methods of struggle consist in the processing of the culture and the soil under it with special or home-made solutions. Of the drugs, they have proven themselves well:

  • Fitosporin-M for onions and garlic;
  • Gamair;
  • Planriz;
  • Alirin-B;
  • Glyocladin.

2-3 weeks before harvesting root crops, chemical treatment should be stopped. To protect plants from powdery mildew, it is recommended to continue spraying, but using folk remedies.

There are also folk methods that are preferred by most gardeners:

  • a solution of 9 liters of water, 1 liter of low-fat milk, 10 drops of iodine;
  • weak solution (slightly pink) potassium permanganate;
  • onion peel infusion;
  • a mixture of water (9 l) and whey (1 l);
  • infusion of ash (for 8 liters of boiling water, half a bucket of ash).

What does gray mold look like?

The infection persists well on the planting material, infecting the soil and, accordingly, the entire crop through loose flakes. When pressed on the turnip, the skin sags in the neck area, and a gray plaque is visible on the surface.

The fight against the disease consists of the following activities:

  • disinfection of seedlings before planting;
  • soil enrichment with phosphorus-potassium fertilizer;
  • timely removal of damaged plants from the plantation;
  • moderate watering and control of soil moisture levels;
  • correct collection of root crops;
  • airing and drying the onions after harvesting;
  • creation of conditions for storage of crops;
  • periodic bulkhead to remove rotten turnips.

Bacteriosis and its treatment with chemical and folk remedies

With high humidity, and in warm weather, putrefactive bacteria penetrate the onion scales and infect healthy fruit.

Decay can occur directly in the soil, but most often bacteriosis manifests itself during the storage period of the crop. To identify the fruits simply by the characteristic smell, swollen skin.

The remnants of last year's fruits can provoke the appearance of harmful bacteria on the soil, so the beds must be dug up after harvest. Onions are planted on an infected site no earlier than 4 years later.

Fusarium rot and how to get rid of it in spring and autumn

The disease is infectious, the pathogen is in the ground, where infection occurs. The bottom of the turnip during development is affected by rot, as a result of which the greens first die, then the root part. Among the reasons provoking the formation of the pathogen in the soil:

  • waterlogging during irrigation;
  • harvesting in rainy weather;
  • late harvesting of fruits;
  • drought during the ripening of the turnip.

As a preventive measure, it is recommended to carry out the following procedures:

  • before planting, the seedlings must be disinfected;
  • when choosing seeds, preference is given to early and mid-season species (they are less susceptible to infection);
  • observe watering norms, avoid waterlogging of the soil;
  • to collect root crops in dry weather.

If an affected onion is detected, it should be removed from the garden and the soil should be treated with Bordeaux solution (1%).

Bacterial rot of onion testes

Often, rot affects the turnip with an excess of moisture in the soil. The reason is prolonged rainfall and the type of soil that prevents the rapid absorption of precipitation. At first, mold forms in the neck of the onion, dropping over time along the testes. Such a crop cannot be stored for a long time, the decay process cannot be stopped.

A turnip is usually not used even for obtaining seeds, such material is affected by a fungus and is not capable of producing good shoots.

Experts recommend observing the following rules for prevention:

  • before planting, the seedlings must be disinfected;
  • irrigation is carried out under constant control of the degree of soil moisture;
  • regularly clean the beds from affected plants;
  • harvest should be done only in dry weather;
  • ensure proper storage conditions with a temperature range from + 5 ° to + 8 ° and ventilation.

The main pests of onions and protection against them

Yield can be reduced not only by diseases, but also by various pests that prefer to settle on onions.

How to deal with an onion fly?

What does a parasite look like? Outwardly, the onion fly (carrot) practically does not differ from ordinary insects, but its great passion for onions can ruin the harvest. She flies out with the beginning of flowering dandelions and appears in the gardens. The fight against the pest should start with prevention, this will allow you to grow environmentally friendly fruits. When using insecticides, toxic substances of the agent accumulate in plants and soil, therefore it is undesirable to use them. When planting and caring for onions, the following rules must be observed:

  • Before planting, the seedlings should be prepared: warm up for several days at a temperature of 23-25 ​​°, soak in a saline solution (1 liter of water per 1 tablespoon of salt) - 3 hours, then repeat the procedure, but already in a manganese bath - 2 hours.
  • Choose a place for beds that is well ventilated. It is recommended to place onions and carrots in the neighborhood. For both crops, this will provide additional protection against pests.
  • Change the place for planting onions annually. In late autumn, with the onset of frost, you need to dig up the ground well so that harmful bacteria and larvae die.

With a massive invasion of flies on the plantation, it is unlikely that it will be possible to do without chemicals. Popular ones: Bazudin, Aktara, Mukhoed.

In order not to use chemicals, many gardeners use folk methods. The most effective are:

  • a solution based on ammonia (for 10 liters of water, take 3 drops of iodine, art. ammonia, several crystals of potassium permanganate);
  • a tincture of aromatic herbs (for 10 liters of boiling water, add several sprigs of valerian, wormwood, mint);
  • coniferous broth (half a bucket of spruce or pine needles are brewed in 10 liters of water);
  • wood ash powder;
  • dusting from ash, red hot pepper, tobacco leaves.

In addition to the above methods, you can treat the garden bed with salt at the rate of 300 g of salt per bucket of water. The main thing to remember when using this method is to spray the onions with clean water to rinse the salt off the feathers. With successful processing, the flies will stop flying over the onion and will not lay eggs in the beds.

In addition, piperazine helps to cope well with the pest. It is applied at the rate of 1 package per bucket of water. All affected areas must be sprayed.

Presowing processing of onion sets from an onion fly is carried out in early spring. It is necessary to spray the entire garden bed. The preparation zemlin also helps well in the fight against the pest, you can always find out how to apply it in the instructions.

Onion mite and treatment for it

Before planting onions, the soil is fertilized. This is the environment the tick chooses for itself. You can identify an insidious pest in the garden by its characteristic features:

  • deformation of feathers with the formation of a white coating on them;
  • shrinkage of the plant due to moisture loss;
  • the formation of mold and mildew.

Fighting a tick is a long and laborious process, because the parasite can sleep and wake up for a long time under favorable conditions. It is more efficient to use several methods at the same time. In case of late detection of insects or signs of their presence, acaricides and insectoacaricides should be used (Ditox, DI-68, Nugor, Fostran, Dimethoat-400, ProRogor, Danadim, Kinfos). These are potent chemicals, so you need to prepare the solution strictly following the instructions.

Do not use pesticides in the fight against mites. The product is addictive to insects, so the treatment will be ineffective.

In order to prevent pests, the following methods are used:

  • careful bulkhead of the seed during storage;
  • preparation of seedlings for planting (sorting and warming up);
  • disinfection procedure;
  • regular treatment of the beds with decoctions of herbs, nettle infusion.

Onion thrips

The female insect lays the larvae inside the onion feather. The parasites feed on the sap of the plant, as a result of which the greens become covered with yellow spots and dries up. A turnip without feathers develops very slowly. As a result, the root crop will not meet the quality standards for flavoring and dimensional data.

To prevent the settling of thrips on onion beds, it is recommended to carry out the following measures:

  • change the place of planting onions in the garden every year;
  • store planting material under proper conditions;
  • follow the rules for preparing and planting sevka;
  • removal from the garden of the entire crop and tops;
  • digging the soil in late autumn.

How to process onions?

In case of large-scale damage to the plantation, special preparations are used:

  • Aktara;
  • Fitoverm;
  • Karate;
  • Spark Gold;
  • Zeon et al.

When using chemicals, you should not eat greens.

You can also try folk methods:

  • Placement of sticky tape for flies between beds as traps;
  • planting nearby onion plantations of fragrant herbs, marigold flowers;
  • spraying with infusion of tobacco leaves (leave for 3 hours);
  • treatment of plants with infusion on celandine leaves (leave for 48 hours).

Reasons why onions turn yellow in the garden and what can be done

Not always yellowed spots on winter onions indicate the presence of diseases or pests.... Sometimes the reason can be a lack of nitrogen in the soil. It is quite simple to remedy the situation - to introduce nitrogen-containing fertilizers into the soil. For these purposes, organic and mineral baits can be used. You can also feed a green vegetable with ammonia. It is an excellent fertilizer, and also allows you to get rid of flies and other pests.

Water with ammonium nitrate with caution according to the instructions. In addition, you can pour and sprinkle the onions with kerosene. It helps to protect the crop from onion flies. You need to process the bed with the calculation of 2 tbsp. kerosene on a bucket of water. This measure will help preserve the harvest and you can not be afraid of a repetition of infection.

Yellow feathers can also indicate insufficient crop care. Each variety has specific cultivation characteristics. Planting different species, few people are interested in the intricacies of growing a certain hybrid. Experienced gardeners recommend in the selection process to get acquainted with the description of the plant and the rules of care.

Unfavorable weather conditions can provoke the formation of yellowness on the batun. As a result of prolonged rains, feathers change color and deform. Or from too hot summer, under the influence of intense sunlight, the feathers begin to dry out prematurely. In such cases, the plants can be helped with a cover made of film or agrofibre. Treatment in this case is not required. You need to fertilize the vegetable as usual.

Early diagnosis of the problem will not only save the crop, but also prevent soil contamination. You should not hesitate with processing, because pests and diseases very intensively destroy plants.


They can damage the culture both directly during growth and during storage. Most often these are several types of insects.

Onion fly

The insects themselves and its larvae cause harm. The signs of damage include wilting of seedlings at the stage of the first leaf. Usually the necks of the bulbs are damaged, and the bulbs themselves are eaten from the inside. With severe damage, the bulb rots and the leaves wither. All this leads to the death of the plant.

Insect years usually fall on the period when dandelions and lilacs bloom. You can fight with the following means:

  1. Flycatcher. They are introduced into the ground when planting bulbs at a dosage of 50 g per 10 square meters.
  2. Medvetox. They are also introduced into the soil and loosened. Dosage - 30 g per square meter
  3. Zemlin. The dosage is the same as that of Medvetox, applied in the same way
  4. Muravyin. The dosage and soil are the same as those of Zemlin.

Onion hoverfly

Also referred to as onion root. It is rare, damages the bulb itself and roots. It makes itself felt with the help of yellowed leaves. The bulb becomes soft and rots. If there are many parasites, the bulb is destroyed from the inside. In this case, a specific smell is observed. The control methods are the same as with the onion fly.

Shallot aphid

Often it is the person who brings it on the planting material and with "under-catch", which is planted together with new batches of the plant. Inhabits young and scaly leaves, which are under the outer wrapper of the bulb. At the same time, the leaves wither and bend, and the affected plant lags behind in growth. Aphid skins and honeydew can be found on onion feathers. You can fight by soaking before planting the bulbs in cold water, thorough weeding and infusions of plant tops with insecticidal properties.

Thrips tobacco

Also called onion. Most often it lives on soil soils. Makes itself felt by drying fleshy scales. The leaves are damaged, the bulbs themselves become small. The seeds lose their germination and dry out.


To fight, you need to spray the onion during its growing season. Means such as EDG, Karate-Zeon, Aktara or ISS are suitable.
You need to process it twice a season and it is desirable that there is a week-long break. Fluids are needed from 200 to 300 liters per hectare.

Onion rattle

It is a beetle that damages many plants. You can determine its presence by through holes in the leaves of onions and breaks. Leptocide is used to fight, as well as Proclay and Spintor.

Four-legged onion mite

Also called tulip or four-legged. Transfers the onion striped mosaic virus. It makes itself felt in the form of green and yellow spots on the scales of onions. During the vegetative period, the tips of the leaves turn yellow in the plant. The bulb can dry out, and its seedlings are often deformed.

Onion mite

Often it affects onions already in the vegetable store. The thinned bottom and decay of the onion can tell about its presence.

Prevention is important when fighting ticks. This is the cleaning and disinfection of vegetable stores, as well as the selection of damaged bulbs.Before planting, onions are processed with such a tool as Actellik (0.1%), the earth is treated with a solution of BI-58 New.

Onions should be planted after crops, perennial grasses or cucumbers, or after legumes.

Important! If you have a small area, you do not need to use pesticides. So, the smell of carrot leaves scares the onion fly. In addition, the smell of wormwood tincture will repel insects. The beds can be sprinkled with wood ash, as well as a mixture of slaked lime with ash from cigarettes.


How to understand that the onion is sick

Diseases and pests of onions, batun onions, as well as other species and botanical varieties of plants are the main reason for a decrease in yield and storage losses.

The culture is susceptible to diseases of fungal, bacterial and viral origin... The development of the disease is often associated with a violation of the rules of crop rotation and agricultural technology of plant cultivation.

Botanically, the onion belongs to the lily family. Like other members of this family, onion plants need protection from harmful microorganisms and insects that carry diseases.

Signs and symptoms

Diseases develop both on the aerial parts of the plant and inside the bulbs. Fighting with them is mandatory, otherwise there is a great risk of losing the harvest.

The development of the disease is evidenced the following signs:

  • yellowing, wilting and deformation of the feather
  • the appearance of stains and mold on onions
  • changes in the structure of tissues of leaves and bulbs
  • black dots on the bow.


Onion moth

A small butterfly, which has survived the winter on plant debris or on the walls of premises, starts laying eggs in early summer. This is done by an onion moth on the underside of a leaf, root crop or flower arrow.

Soon the larvae appear, which do the main harm, eating the flesh of the foliage, gnawing the bulbs, inflorescences. They pupate on plant debris and weeds or in the soil, giving birth to a new generation of butterflies soon.

The pest affects the plant throughout its development, because it can give 2-3 generations per season.

Treatment is carried out with the following chemicals:

  1. Spark - processed in summer and at the stage of larval appearance.
  2. Summer Resident and Metaphos. The drugs are used strictly according to the instructions.

Onion pests are also fought with the help of folk remedies. To do this, use the following infusions:

  • ash: pour boiling water into 0.3 kg of ash, insist, strain, stir in 40 g of liquid soap
  • garlic: chop the teeth in a meat grinder, mix with water in equal proportions, close tightly and leave for about a week in a warm room. For treatment, add 70 g of the product in 10 liters of water
  • tobacco: in a container with 0.2 kg of tobacco and 1 tbsp. l. pour soap in hot water, strain after cooling. Then you can treat plants and soil using 1 m2 liter of mixture
  • pepper: put a kilogram of red capsicum, cut into 2 parts, in a bucket of boiling water, boil, drain the cooled liquid and pour into storage containers. Before processing, 130 g is diluted in 10 l of water together with soap (40 g).

Treatment with infusions is carried out several times after planting the bulbs at intervals of a week.

Wormwood or calendula infusions will help to defeat the mole (they have a frightening smell). Also for this purpose, the method of mulching with peat, humus or chopped spruce branches is used.


Onion pests and the fight against them

Onions suffer from pests less often than other garden crops, because they contain phytoncides - substances that repel insects. However, some parasites still pose a threat to him.

Onion fly

The main pest of the culture is the onion fly, which differs from the usual light ash color. The parasite lays eggs in the beds and directly in the irregularities on the surface of the seedlings. After hatching, the larvae begin to feed on the bulbs and gnaw numerous passages in them.

You can recognize a fly by wilting green feathers and slowing down the development of plants. A characteristic feature is the appearance of an unpleasant odor - it indicates decay of the bulbs. If you carefully examine the plantings, then white larvae can be found under the upper scales of the turnips.

The onion fly begins to harm plantings in late spring.

There are several ways to get rid of an onion fly. In particular, they apply:

  • dusting with tobacco dust
  • spraying with ammonia diluted in a volume of 45 ml per bucket of water
  • treatment with drugs Aktara, Diazinon and similar.

Autumn digging of the soil is a good prevention of onion flies. Before planting, sevok should be treated with a light pink solution of potassium permanganate to strengthen immunity.

Thrips

Onion thrips outwardly resembles a small mosquito with a narrow light yellow or brownish body and fringed wings. Adult pests and whitish or greenish larvae feed on the cell sap of the pulp and feathers of the plant. You can find out about the appearance of thrips by the light and brownish spots on the bulbs and by the yellowing of the tips of the leaves.

Thrips hibernates in plant debris, so in the fall all garbage in the beds must be removed and burned

The fight against the pest is carried out using the drugs Aktara, Fufanon and Actellik. The funds are diluted according to the instructions and sprayed the plantings several times per season, but no later than a month before harvesting. You can also use a tobacco solution and an infusion of celandine. So that the insect does not harm the already harvested crop, the basement or attic must be fumigated with a sulfur stick.

Root onion mite

Onion mites damage plantings in wet and hot weather. It is especially difficult to notice it - the insect lives underground, has a whitish color, and does not exceed 1 mm in size. But the characteristic symptoms allow suspecting the presence of a tick on the onion. The feathers are deformed and covered with a white bloom, and the turnips lose moisture, wrinkle, become loose and rotten. The scales develop yellow spots or moldy patches.

The fight against onion mites is carried out using insecticidal and acaricidal agents - Aktara, Iskra and Aktellik. You can also use nettle infusion - 100 g of leaves are brewed in 500 ml of boiling water and left for five days, and then diluted with 5 liters of water and water the beds. To prevent the appearance of a pest, seedlings or seeds are warmed up before planting.

Bulbs with signs of tick damage should not be stored - they must be thrown away immediately

Hoverfly

The onion hoverfly, or small daffodil fly, has a bronze or greenish shell and reaches 7 mm in length. The pest mainly affects underground turnips with cracks and wounds, often attacks plantings that have already been damaged by other insects. The parasite slows down the normal development of the onion, leading to yellowing and wilting of feathers from top to base. Underground culture heads soften and begin to rot, and an unpleasant odor often emanates from the beds.

Onion hoverfly begins to harm plantings in June

If a hoverfly is affected, the affected bulbs must be removed from the soil and destroyed. The remaining plantings are spilled with a saline solution prepared at the rate of 200 g of powder per 10 liters of water. The first treatment is carried out when feathers grow up to 5 cm, the second is carried out after three weeks.

Stem nematoda

A dangerous pest of onions is a nematode. The insect infects the crop in late summer, shortly before harvest. First, the white translucent worms feed on the succulent feathers of the plant, and then go down to the bulbs and begin to absorb the pulp.

You can recognize the stem nematode by deformation of the leaves and white bloom. When damaged by a pest, the feathers of the plant quickly turn yellow and dry out. It is almost impossible to effectively fight the nematode, since by the time alarming symptoms appear, the parasite has time to cause serious damage to the underground bulbs. The heads of the vegetable rot and give off an unpleasant odor; when removed from the soil, numerous white worms can be seen on them.

Treating the soil with ammonia solution before planting onions helps prevent stem nematode

You need to fight the pest prophylactically. Onions are warmed up and disinfected with a solution of potassium permanganate before planting. The land in the garden is carefully dug up, fertilized with peat and sand and deoxidized with lime. Onions are grown in one place for no longer than one year, and they are returned to their previous site only after four years.

Onion weevil

The weevil has a small dark gray body up to 2.7 mm and a long curved proboscis. Insect larvae look like light caterpillars with dark heads up to 6.5 mm long.

The parasite feeds on onion juice, begins to harm plantings in the spring immediately with the onset of heat. Adult insects eat the plant debris in the beds and lay their eggs inside the green feathers. The hatched pest larvae make holes in the young leaves of the onion and result in white or light yellow spots.

The best prevention of weevil is the annual autumn cleaning of the beds and careful digging

Weevil control is carried out in standard ways. With a strong defeat of the plantings, the bulbs affected by the pest are simply destroyed. The remaining copies are treated with Aktar and Aktellik means 3-4 times per season in accordance with the instructions. At the same time, you cannot eat green onion feathers.

Onion moth

The adult insect is a small brown butterfly, and the larvae look like yellow-green caterpillars. The pest feeds on both feathers and underground onion heads; in June, it lays eggs on the outer part of the leaves and on the surface of the turnip.

You can notice the moth with a close examination of the landings. The appearance of the pest is indicated by the yellowing of the tips of the feathers and the appearance of holes in the greenery. In the absence of a fight, the moth is able to completely eat out the aerial parts of the onion from the inside.

You can destroy the larvae and adult parasites with a solution of ammonia or with Iskra and Metaphos. Treatments are carried out up to four times per season, since the moth gives 2-3 generations from spring to late summer.

The adult onion moth is well scared away by dusting the beds with wood ash and tobacco

Onion cracker

The cracker, or firefighter beetle, appears in the garden in the middle of summer. It is quite simple to recognize the pest of the testes of onions and their feathers - an adult insect has a bright red shell and is clearly visible against the background of greenery. The presence of the parasite is also indicated by holes in yellowed leaves.

The firefighter beetle is called the crackling beetle because of the characteristic high-pitched sound that it makes in case of danger.

A good measure of pest control on onions is hand picking, since the insect is clearly visible in the beds. Insecticidal agents help to get rid of the larvae - Decis, Mospilan, Karate.

Onion scoop

The scoop butterfly is a small moth with gray-brown wings, on which whitish stripes are noticeable. Onions are threatened by insect larvae - green or pinkish caterpillars, eating feathers and gnawing the flesh of underground turnips. Drying of the greens testifies to the appearance of the pest, the heads of the vegetable become unsuitable for human consumption.

An adult scoop flies mainly at night, so it is difficult to notice the pest in the garden in time

To eliminate scoops, drugs Aktara, Tsitkor and Fufanon are used. Thorough loosening of the soil helps to prevent infestation of the beds. In this case, insect eggs end up on the surface and cannot develop normally, and the hatched larvae quickly become food for birds.

Green or gray aphids often attack feather-grown onions and appear on the plant in May or early June. In the absence of a struggle, it attacks plantings with large colonies and densely sticks to the aboveground parts of the culture. It is easy to see the parasite upon close examination, and the deformation of the leaves also indicates its presence, they curl and bend.

Aphids not only harm onions directly, but also carry dangerous viral diseases.

The fight against the parasite is carried out by dusting with wood ash, a solution of laundry soap brings a good effect. To scare away pests in the garden, you can plant marigolds, garlic and white mustard. The insect does not like these crops and rarely appears in close proximity to them.


Onion pests: description, photo and fight against them

Onion fly, or onion flower girl

Basic information. Onion fly is a dangerous pest of onions. It slightly damages onions, leeks, shallots, very little damages garlic and chives. Also damages bulbous flower crops, especially tulips. Causes significant damage to the salad.

Significant harmfulness is noted during the years of mass flight of flies during the growth and beginning of onion development. Onions sown with seeds to obtain sets suffer especially from damage. larvae with a dense stalk crawl from dead plants to healthy ones, often overcoming a distance of more than 0.5 m. When growing onions from seedlings, when there is no need for thinning and the risk of infection is minimized, the harmfulness is lower.

Onion plants affected by neck rot or stem nematode are especially severely damaged by the larvae of the onion fly Delia antiqua and the sprout fly Delia platura.

In the middle lane it gives 2 generations, in the northwestern regions - usually only one, but with a warm autumn and the second. The development of the third generation is possible in the southern regions.

Signs of damage. Seedlings in the cotyledon or first leaf phase wither in groups inside the bulbs, the larvae passages - at the base of the cotyledons and leaves the larvae themselves. In older plants, the leaves in the neck of the bulb are damaged outside from the side of the bottom or neck, a small hole. During the growth phase, the leaves in the neck of the bulb are damaged from the inside or the bulb is damaged, as a result of which the leaves wither. The leaves turn yellow, the bulb rots, the plant gradually dies.

Regardless of the type of damage, onion sets die when only one or two onion fly larvae are introduced into the plant. The same is observed on turnip onion plants if their growth point is damaged.

Description of the pest. Adults are ash-gray, body length 6-8 mm. Legs are black wings slightly yellowish. The male has a dark stripe along the abdomen of the hind tibia with a row of short thick setae.

Eggs are white, elongated, about 1.2 mm. The larvae are worm-like, dirty-white, rounded with the ventral and back sides, narrowed towards the anterior end, body length up to 10 mm; hook-shaped jaw. On the posterior segment, there are two round dark-colored plates with respiratory holes. Pupae are in a yellowish brown pseudococone.

The spring flight of onion flies coincides with the flowering time of the dandelion or lilac. Reproductive maturation occurs with additional nectar feeding for a week.

On sowing of black onions, egg-laying is already noted from the phase of 2-3 true leaves. Females place eggs on onion shoots, between leaves or under lumps of soil near plants in groups of 5-20 pcs. The spawning period lasts up to 1.5 months.

Egg development normally occurs at 25-80% soil moisture. Embryogenesis lasts about 6 days at a temperature of 13 ... 14 ° С, about 4.5 days at 17 ... 22 ° С or from 6 to 3 days in the range of 23 ... 29 ° С.

The larvae penetrate the flesh of the bulbs, gnawing through the base of the leaves in the neck, less often from the side of the bottom. Individuals hatched from one clutch stick together, eating out a common cavity. They can migrate to neighboring plants. Duration of development of larvae is 2-3 weeks. Larvae pupate near damaged plants in the soil.

The second generation of onion flies appears in July. Pupae overwinter in areas where onions were grown, at a depth of 10-20 cm. Often, underdeveloped larvae can be carried on bulbs to storage facilities where they pupate.

Onion fly control. The drugs are used:

  • Flycatcher at a rate of 50 g / 10 m2 by application to the soil surface when planting bulbs
  • Medvetox at a rate of 30 g / 10 m2 by applying to the soil surface when planting bulbs with simultaneous loosening
  • Ant at a rate of 30 g / 10 m2 by applying to the beds immediately after sowing,
  • Earthen at a rate of 30 g / 10 m2 by applying to the soil surface when planting bulbs with simultaneous loosening.
  • Tobacco dust or Tabazol is also used by dusting during the growing season at a rate of 3 g per 1 sq. M.

Onion hover, or onion rootworm

Basic information. It appears occasionally, but it causes strong damage to onions and bulbous flower crops. Also damages root crops of carrots and beets, potato tubers. Hoverflies, in contrast to the onion fly D. antiqua, harm in the second half of the growing season.

Together with the onion hoverfly, there is a tuberous hoverfly, which differs from the first in that males have a small tubercle at the base of the hind femora.

Signs of damage. Damaged plants lag behind in growth, the ends of the leaves turn yellow and wither. The bulbs soften, and when they decay, they acquire a specific smell. With group meals, the inner part of the bulb is destroyed, turning into a black rotting mass.

Description of the pest. Medium-sized stocky flies, body length of female 5-7 mm, male 5-6 mm. In males, the apex of the abdomen is slightly swollen, in females it is flat. The body color is bronze-greenish, on the back there are two light gray stripes. Antennae are black. The abdomen is metallic green, blue or black throughout. The thighs of the hind legs are thickened. The feet are black or black-brown.

Females lay up to 100 eggs on already weakened plants, often damaged by onion flies or stem nematodes. Oviposition is carried out in small groups on bulbs.

Shallot aphid

Basic information. A dangerous pest of forcing onions harms other onions as well. May damage strawberries. The scientific name comes from the main food plant - shallots.

The settlement of aphids is carried out under the influence of an anthropogenic factor. The pest enters greenhouses with planting material, on bulbs and under-catch, which is planted together with new batches of onions. In greenhouses, aphids are most harmful to forcing onions in the autumn-winter and early spring periods.

The shallota aphid is an incompletely cycled species. In the greenhouse, the aphid goes through an unfavorable period on the weeds and in the bulbs between the scales. In addition to greenhouses, it winters and also harms in vegetable stores. After planting onions in greenhouses, the aphids move on to feed on juicy scales and leaf bases. As a rule, there are no winged females. The main reserve of the pest is under-catch onions, which did not have time to form a commercial feather. It is from him that aphids move to new plantings. Aphids are known to carry some viruses.

Signs of damage. Shallot aphids are found on scaly leaves under the outer wrapper of the bulb and on young leaves. Affected plants stunted, leaves bend and wither. The feather that goes to the greens becomes contaminated with honeydew and molted skins.

Description of the pest. The body is ovoid, brown or red-brown in color. The larvae are greenish brown or dull yellow. The eyes are black-brown. Antennal tubercles are well developed, converge in front. Antennae are longer than body. The 4th-5th segments and the Spitz of the 6th antennal segment are black. The rest of the segments have body color. The tubes are cylindrical, light, taper towards the apex, but end in a small darkened funnel. The thickness of the tubes is 8 times less than their length.

Protection measures. Pesticide treatment of onions on feathers is prohibited. The use of biological agents is difficult and economically unprofitable. Therefore, a special role in the fight against the pest is assigned to agrotechnical methods.

  • soaking the bulbs in hot water before planting
  • storage and growing of "under-catch" separate from the main massif
  • weed removal and preventive maintenance between turns.
  • it is possible to use infusions from the tops of insecticidal plants.

Thrips tobacco, or onion

Basic information. Tobacco thrips severely damages onions, weaker - shallots. Garlic suffers little from thrips damage. The pest damages both the feather and the bulbs themselves during storage. By the time the onions are harvested, most of the thrips migrate to other crops and weeds, where the adults feed before hibernation. Part of the thrips is taken under dry onion scales, and thus the pest is brought into storage. The quality of marketable onions, as well as onion sets, is greatly reduced.

Distributed in the southern and middle lane in the open ground, to the north it is found as a pest of greenhouse crops.

Signs of damage. The fleshy scales become rough, later they dry out. Whitish-silvery or whitish stripes and spots appear on green leaves, among which small dark spots are noticeable - dried excrement. The quality of the onion on a feather decreases - severely damaged leaves acquire a completely whitish color, often bend, turn yellow, dry out.

Due to the suspension of growth, the bulb is small. Inflorescences of onion testes, significantly populated with thrips, give shriveled seeds of low germination or dry out. Damage to onions by thrips together with sun exposure is very dangerous for plants.

Description of the pest. The imago is elongated with narrow wings folded along the body. Body length 1.0-1.3 mm. The general color is yellowish. Eyes red antennae, usually yellow. The forewings are slightly darker than the hindwings, with a fringe of fine hairs. Antennae 7-segmented, i.e. their stylus is 1-segmented; the jaw palps are 3-segmented.

The egg is reniform, whitish, 0.25-0.26 mm long and 0.15 mm wide. The larval stage has 2 instars. The hatching larva, whitish or light yellow, soon begins feeding on the plant. As they grow older, a greenish-yellow intestine begins to shine through in the abdomen. The body length of the 2nd instar larva is 0.8-0.9 mm. They do not feed, they are usually found in the soil.

The imago of tobacco thrips overwinters in all kinds of plant residues in greenhouses and in the greenhouse area in the upper layer of the substrate, as well as under dry scales of bulbs in vegetable stores.

Fertility of the female is about 100 eggs. She places them one by one under the skin in the leaf tissue. The larvae hatch after 3-6 days. The development of one generation in the southern regions takes 14-30 days to the north, development is slower.

Protection measures. Effectively spraying plantings during the growing season with Aktara, VDG preparations - 2 times per season. Karate Zeon, ISS - 2 times per season, fluid consumption 200-300 l / ha. The waiting period is 25 days.

The main thing in the fight against the pest of onions is to carry out two treatments close in time with an interval of 5-7 days. This is due to the fact that some of the individuals at the egg and nymph stage are highly resistant to drugs or are inaccessible to them.

Onion cracker

Basic information. It affects onions, onions, chives, garlic. It also feeds on lilies, hazel grouse and other plants from the Amaryllis family. It is ubiquitous, but damages with foci.

The onion rattle is often confused with the lily rattle, which has a black head and legs instead of red. In the middle lane, the leaf beetle develops in 1 generation, in the southern regions - in 2 generations.

Signs of damage. Onion rattle beetles gnaw through holes in onion leaves, as a result of which the leaves break. The larvae eat holes in the onion leaves and in the arrows, gnaw the flower stalks. Adult larvae usually penetrate into the tubular leaf.

Description of the pest. Bright red beetles, 6-8 mm long. The legs are red, the antennae and the underside of the body, except for the tip of the abdomen, are black. The eggs are elongated, smooth, orange in color, 1 mm long. The larva is thick, off-white, with black dots on the sides, six-legged. The head, chest shield and legs are black. The larvae cover themselves with their own excrement, resulting in a brownish mucous mass.

Basic information. Onion cracker damages onions, leeks and garlic during the growing season. The harmfulness is especially high on weakened, stunted plants. Distributed in the European part of Russia and the Far East.

To combat the onion rattle, the drug Lepidocide is recommended. Against lepidoptera, preparations Spintor and Proclame are also effective, used in the system of integrated management of the number of phytophages.

Four-legged onion mite, or tulip, or garlic

Basic information. A widespread pest - known from the Moscow region to the Krasnodar Territory. Harms onions, garlic, many ornamental crops of the Amaryllis family. The mite inflicts maximum harm during the storage period of the onion: weak plants with ugly or dwarf shoots and flowers develop from damaged bulbs in the future. The garlic mite is the carrier of the Onion mosaic virus. The virus is acquired by the prelarvae of the tick in the process of feeding on the cells of the bulb for 15 minutes. After molting, it remains in the body of females for 9 days. The virus is not found in eggs.

The primary spread of the tick occurs with the planting material, and secondary - with the help of wind and insects.

Signs of damage. Green or yellow spots appear on the fleshy scales of the onion. During the winter storage period, the damaged scales dry out, which makes the spots more visible. During the growing season of the onion, the tops of the leaves turn yellow. In spring, garlic mites migrate to leaves and flowering shoots, which become chlorotic with a whitish color. Seedlings damaged by a mite are deformed, often twisted in a loop, the plants lag sharply behind in development and growth.

Description of the pest. The female is about 0.2 mm long, the body is highly elongated, whitish in color, with 2 pairs of legs located in the front of the body. The shield is semicircular, without a visor. The skin has annular grooves. Dorsal half-rings on average 83-87, abdominal up to 76. Genital scutellum with longitudinal ribbing. The tibia of the legs of pair I has one strong seta. Larvae from adults outwardly differ in smaller size and fewer semirings on a relatively short body.

The garlic mite hibernates in all phases of development between the scales in the bulbs. Most individuals concentrate in the area of ​​the neck, bleaching it. In cold storage conditions, mite development slows down. Under favorable conditions in the storage, the mites begin to reproduce, and when the temperature rises to 18 ... 25 ° C, they settle on neighboring bulbs.

Females lay 1 egg per day, but over the entire life span they are able to lay up to 25 eggs. At a temperature of 9 ° C, eggs develop for 3-5 days. Under favorable conditions, the duration of generation is 9-10 days. In dry conditions, migratory ticks die, but in a humid environment they can survive without food for up to 80 days.

Onion mite

The most intensive accumulation of turnip on onions is observed during the storage period. Bulb damage usually begins at the bottom, but mites also invade bulbs damaged by insects, nematodes and molds. Through the worn out and rotten mass of the bottom, the mites settle inside the bulbs between the fleshy scales. Damaged bulbs rot.

In vegetable stores, if the storage technology is not followed, when humidity increases in a large layer of onions, and ventilation does not provide drying, the tick multiplies rapidly. When the relative humidity drops to 60%, the reproduction of the root onion mite stops and hypopuses appear.

Females lay an average of 400 eggs between the fleshy scales of the bulb within 2 months. The development of one generation lasts more than a month at a temperature of 15 ° С, at 18 ° С - 27 days, and at 21 ° С - 14 days. Under optimal temperature conditions, one generation develops within 9-11 days. For a year, the pest may give up to 16 generations. The tick leads an active life in the temperature range from 5 to 32 ° C. But when the relative humidity is below 60%, reproduction stops.

Protection measures. Preventive measures form the basis of the struggle.

Vegetable stores are cleared of plant residues before the new season. They are disinfected by fumigation by burning sulfur bombs Climate or FAS at the rate of 30 g per 1 m3 of the room. Gasification with sulfur dioxide is carried out in a hermetically sealed storage with exposure for 24-36 days. Then the store is ventilated for 48 hours and bleached with milk of lime.

Before putting the onion for storage, first dry it well in an open space, and then at a temperature of 35 ... 37 ° C for 5-7 days. Infected seedlings are fumigated with sulfur dioxide for 2 days before laying them for storage or sprinkled with dry chalk.

Damaged bulbs and plants are discarded before planting and during the growing season. It is necessary to harvest in dry weather, cut the tops.

Agrotechnical techniques. Onions should not be grown in monoculture. Placing crops or planting onions in a 3-4 year rotation after perennial grasses, legumes, cabbage, cucumber or other predecessors. Winter plowing is carried out with the incorporation of plant residues.

Chemicals. In the spring, before planting, the uterine onion is treated with a 0.1% Actellik solution, then dried under natural conditions. Spraying with BI-58 Novy solution is carried out on plots with sowing.

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How to deal with pests?

Unfortunately, there is no single scheme for controlling onion pests. The list of manipulations directly depends on the type of insect. So, an infusion of herbs with a pungent smell will help get rid of onion flies and onion hoverflies: garlic, wormwood, tobacco, hot red pepper. Fertilizing with urea will help scare off pests. In order to prevent, the bulbous beds are covered with mulching material.

If the garden bed is attacked by weevils, infusions of plants with a strong aroma are used as weapons. The insect will definitely not covet onion, from which the smell of celandine, mustard or tansy emanates. In addition to spraying plants, you can generously sprinkle with chopped dry herbs. The beds are dusted with wood ash and tobacco leaf powder.

To get rid of onion thrips will help all the same "aromatic" mixtures. The most effective remedies are prepared as follows:

  • 1 kg of wormwood is placed in a saucepan and 3 liters of water are poured, after which the mixture is boiled for 20 minutes and cooled. Spray onions 2 times with an interval of 7 days.
  • Stir 2 g of mustard powder in a glass of water. The mixture is insisted for 48 hours. To prepare the working solution, the volume of the concentrate is adjusted to 1 liter.

To prevent the appearance of a pest, organic residues are carefully removed before winter. The instrumentation necessary for planting is treated with a disinfectant. In case of severe infection, onions are treated with chemicals such as EDG, Aktara.

For the destruction of onion moth and a number of other insects, the following agents are widely used:

  1. 300 g of wood ash is poured with boiled water, after which it is left to infuse. For better adhesion, 40 g of soap is added to the cooled strained mixture.
  2. 100 g of calendula seeds are poured into 5 liters of water and left to infuse for two days. The resulting infusion is treated with moth-affected onions.
  3. Finely chopped garlic is poured in a 1: 1 ratio with water and insisted for 14 days in a closed jar. To prepare a working mixture for 10 liters of water add 70 g of concentrate.
  4. 0.5 kg of red hot pepper is cut in half, put into a 5-liter saucepan and boiled. The cooled broth is filtered. Onions are sprayed with a solution of 10 liters of water, 130 g of broth, 40 g of soap.
  5. 200 g of tobacco is poured with boiling water and left to infuse.After the mixture has cooled, it is filtered. Plants and soil are sprayed. Consumption per sq.m. beds - 1 l.
  6. To destroy the onion fly, the soil around the turnips is sprayed with a salt solution. To prepare the mixture, I dissolve 200 g of table salt in a bucket of water. Treatment is carried out upon reaching a height of 5 cm. Subsequent spraying is carried out at intervals of 3 weeks.

If these agents are ineffective in the fight against numerous insects, the onion is sprayed with chemicals. Good results are shown by Proclame, SPINTOR, Decis, Bi-58, Tabazol, Metaphos.

Regardless of the type of insect that attacked the onion planting, it is recommended to use aggressive pesticides only in case of severe infection.

Both the first and second types of spraying are carried out in dry, quiet weather in the afternoon. To achieve a positive effect, the treatment is carried out periodically.

As you can see, the variety of onion pests is quite large. Having found at least one insect on the plants, you need to immediately begin measures to destroy it. If you do not react in time, seemingly harmless bugs will eat the whole onion in a matter of days. To reduce the risk of collision with voracious insects, it is recommended to carry out preventive measures, which consist of observing the rules of crop rotation, soil preparation and seed preparation.


Watch the video: Onions. Diseases. Symptoms. Disease Management