Onions are one of the most important ingredients in cooking. This vegetable is grown in almost every country in the world. But due to a number of obstacles, complete harvesting is not ensured almost anywhere. This is prevented by soil depletion, changing climatic conditions, excessive use of chemicals, and diseases. But the largest percentage of losses is caused by onion pests, and combating them is crucial for obtaining a high-quality harvest.
In order to begin the fight against onion destroyers, you need to learn how to correctly recognize them. In addition to the appearance of the insect, it is necessary to pay attention to the nature of the plant’s lesions.
Onion fly: how to recognize and neutralize?
Every gardener knows that the most dangerous pest for onions is a fly from the hoverfly family. Due to the fact that the insect is very fond of juicy onion fibers, it was nicknamed onion. The pest can be identified at its inception stage. To do this, just inspect the green arrows of the onion. Particular attention should be paid to the area located approximately 2-3 centimeters above the soil.
If white elongated eggs, about 1.5 mm long, are noticed, then it is necessary to remove the affected stalk. This procedure must be done at the end of May - beginning of June, otherwise after 2-3 days the eggs will turn into creamy-white larvae, about 8 mm long. It is much more difficult to eliminate the larvae, because almost immediately after degeneration, they try to burrow into the soil and penetrate directly into the head of the bulb.
At this stage, the upper stems of the plant look absolutely healthy, so it will not be possible to fight the pest locally. Further, throughout the summer and the warm part of autumn, the larvae will turn into pupae. It is the larvae that cause maximum damage by actively feeding on onion pulp.
From some cocoons flies will appear, which will emerge to the surface in 3-4 weeks, and some pupae will remain overwintering in the soil and will regenerate into flies only at the end of next May. If the soil is not properly tilled during the fall harvest, the cycle will repeat again.
Signs of plant damage by onion fly:
- if the bulbs are affected by larvae, the stems first become sluggish and then die off altogether;
- if already infected bulbs were planted, the new shoots will initially look yellowish. And the harvest dug up in the fall will turn out to be rotten.
Features of plant damage by onion thrips
Thrips are very small insect pests of onions that are carriers of diseases of many plants. Thrips can be found on cabbage, potatoes, tobacco, cotton, and zucchini. Insects can be identified by the following characteristics:
- thrips eggs are white-yellow in color, bean-shaped and do not grow larger than 0.5 mm;
- the larvae look like small flies of pale yellow color, but without wings;
- the pupae are very similar to the larvae, but their color changes to dark brown;
- adult individuals look like brown, narrow (up to 1 mm) flies. Moreover, males are wingless, and females have long narrow fringed wings.
The life cycle of thrips lasts from 20 to 30 days, depending on the outside temperature. Egg incubation period: 4-5 days; lifespan of larvae: 5-7 days; Pupa development period: 8-10 days, and the life of an adult fly lasts 5-8 days. 
Thrips feed by piercing the surface of the plant and sucking out the secreted juices. Pests cause direct damage to both stems and bulbs, and can also provoke the development of various diseases in the plant. Damaged bulbs seem to become infected with ulcers, lose color, and the stems dry out. At the same time, green bow arrows become covered with silvery spots. Thrips and leeks attack. Despite the fact that the plant does not have a pronounced bulb, pests happily feed on the white part of the root.
Fighting onion flies and thrips
The methods of controlling the two pests listed above are identical and quite labor-intensive. Firstly, after harvesting, it is necessary to dig up and sift the soil, since pest larvae easily tolerate even the coldest winters. Of course, it is almost impossible to completely get rid of millimeter-sized larvae using this method. Therefore, in the next sowing season, it is recommended to plant corn, carrots, or fragrant herbs in place of the onions. The aromas of these plants are destructive to flies and thrips.
Protecting onions from pests and diseases is impossible without the use of professional products. Treatment of onion roots before planting in the ground with a mixture of 0.1% carbendazim and 0.025% carbosulfan solution will provide immunity from infection by pest larvae for 30-40 days. Also, after planting (but not earlier than 30 days), it is necessary to apply an insecticidal spray. 
Experienced gardeners recommend the use of preparations based on alpha-cypermethrin. You can check the effectiveness of the methods described above in the following way: place ordinary sticky traps of a bright (preferably green) color on the beds. As soon as the strips remain empty for at least a few days, chemical treatment can be stopped.
How to get rid of pests without chemicals?
Those who categorically refuse to work with chemicals can try using neem seed oil. This is a powerful natural insecticide that can disrupt the life cycle of insects at all stages. The oil is biodegradable and non-toxic to pets, birds and people. In addition, it is a natural fungicide that fights mold and fungal infections.
You can purchase the drug at many garden or organic stores. To use neem oil as an insecticide, mix 2 teaspoons of oil, 1 teaspoon of mild liquid soap with 1 liter of water. Pour the resulting solution into a bottle and spray on the green arrows. You need to process the onions every day for a week, then take a break. If new larvae appear on the stems, water the plants again. 
Another natural insecticide is regular garlic. Its strong smell is unpleasant not only to people, but also to garden pests. In fact, garlic spray will not destroy pests, but it will quite successfully prevent their further reproduction.
In order to prepare a natural insecticidal solution, you need to take two heads of garlic and grind them in a food processor with a small amount of water. Infuse the resulting mixture overnight, and then mix with 1/2 cup vegetable oil, 1 teaspoon of mild liquid soap and a liter of water. Spray the resulting solution onto the infected onion. Chili pepper spray has a similar effect. 
Attention! The chili pepper solution also affects people, so be sure to wear gloves on your hands and a protective mask on your face.
Root bulb mite
The root onion mite, despite its name, attacks garlic more often than onions. Ticks are translucent, cigar-shaped, microscopic in size (adults do not grow more than 1 mm in length), and almost invisible to the naked eye. The eggs are attached with a thin adhesive tape to the stem of the plant, and after maturation they are moved into the soil.
Signs of damage to onions by microscopic mites are not very obvious. Pests very slowly grind down the roots and pulp of the bulbs. This leads to stunted plant growth, twisting and discoloration of the stems. But small yellow specks appear mainly at the very edge of the arrows, which means that not every gardener will be able to notice such an important sign in time. Mites can also damage healthy bulbs that have already been dug up. 
To prevent the occurrence of onion mites, it is necessary to avoid sequentially planting onions and garlic in the same bed for several years. Before the start of the summer season, it is necessary to treat the soil with a solution of sulfur (0.3%) and dimethoate (0.03%) or dicofol (0.05%) in an amount of 2 ml. for 1 liter of water. It is recommended to use preparations based on clofentesine as post-sowing soil prophylaxis.
Gnawing (cotton) bollworm
The gnawing armyworm is dangerous only in the form of a caterpillar. The adult cutworm looks like a large light brown moth. When the wings are folded, a V-shaped spot is formed on the back. The butterfly lays single creamy-white eggs. Larvae emerge from them, which degenerate into brown or greenish caterpillars. It is at this stage of life that the cutting armyworm causes the most problems for gardeners.
The larvae are usually located inside the stem, but subsequently (during the transition to the next life stage), they begin to move closer to the soil. The caterpillar burrows into the soil and begins to chew through the white flesh of the onion. As a result, the green stems dry out completely, and the vegetable itself becomes unsuitable for consumption. To get rid of the gnawing armyworm, you can use the same insecticides that are used against thrips. 
Careful cultivation of the topsoil is also recommended. Regular loosening of black soil creates unfavorable conditions for the laying and normal development of eggs. If only root crops are planted at your summer cottage, then you can hang several feeders on the surrounding trees. This is the most natural and inexpensive method of getting rid of pests. Cutworm caterpillars are the best treat for birds.
How dangerous is onion nematode?
The onion nematode is dangerous because it can literally reproduce continuously. The translucent white eggs mature within three days, after which the cycle repeats. An adult nematode looks like a whitish, oval-shaped worm, 2 mm long. Since the life cycle of this pest does not exceed a year, larvae and adults often develop in the same bulb. Ultimately, the dug up vegetable turns out to be hollow inside.
And if an infected onion gets into the warehouse before a clean harvest, then within a few weeks most of the vegetables will begin to rot. Although the nematode is not considered too dangerous, care must be taken to ensure that the pest does not infect any vegetables. Otherwise, the pulp of all the bulbs will very quickly turn into rot. Sometimes infection of vegetables can be caused by mechanical damage or improperly organized storage. 
The simplest and most natural method of preventing the spread of nematodes is to plant marigolds. Pests cannot stand the smell of these flowers. It is advisable to plant marigolds over several seasons as the effect is cumulative. If worms have already infected vegetables, it is recommended to treat the crop with chitosan-based preparations.
In addition, before planting onions, you can flood the soil with chemicals (but this method will kill not only pests, but also beneficial land fauna). If you don’t want to use chemicals, you can add compost, manure, or any other natural fertilizers to the soil. Organic matter is unlikely to kill pests, but it will increase the soil's ability to retain moisture and nutrients. This means that onions will receive additional sources for fast and healthy growth.
- Nematode activity slows when soil temperatures drop. This means that late onion varieties are much less susceptible to pests.
- Before planting the bulbs, you must carefully inspect all the roots. If a whitish coating is noticed, the plant should be thrown away rather than trying to be cleaned or treated with a solution.
- Sometimes nematodes infest the soil so deeply that the only solution is to completely replace the topsoil. This is a fairly expensive option, which will provide a guarantee of getting rid of pests for 1-2 years.
Before starting pest control, it is necessary to assess the extent of damage. If you have a whole plantation planted with onions, then it is worth using chemicals. But if you only have a couple of onions growing in your garden for a homemade salad, you need to try natural remedies.
No garden can be imagined without onions. This healthy vegetable is included in the recipes of many dishes, and is also an excellent medicine that has no contraindications or side effects. With good care, onions can produce an excellent harvest, because they are resistant to adverse weather conditions and are not too demanding on the soil. Onions can be damaged by more than 50 types of pests and diseases. The most important are pests and diseases of the underground parts of onions grown for turnips: onion root mite, fly larvae (onion and hoverflies), bottom rot. Pests and diseases of leaves - onion munchkin, tobacco (onion) thrips, onion downy mildew, smut. During storage, onion mites and gray neck rot can cause significant damage. Depending on the classification and stage of the disease, you should know how and with what to treat onions against pests, what diseases there are.
Disease-resistant onion varieties
Separately, it is worth highlighting winter varieties of onions, thanks to the cultivation of which it is possible to obtain fresh onions for the table all year round, in particular, at the beginning of summer, when winter supplies of vegetables have already come to an end. Early ripening winter varieties are sown in the 2-3 decades of August, late ripening ones - in February and March. The most successful and popular varieties include “Glasir”, “Ellan”, “Swift”, “Alike”, “Radar”, “Yurzhek”, “Eldorado”, “Stimul”.
Pay special attention to the universal varieties of domestic selection Mavka and Lyubchik. Mavka is a mid-season (growing season 102-114 days) high-yielding variety of red salad onion. The bulbs are flat-rounded, dense, weighing 75-100 g. Forms powerful outer scales that protect the bulb well during storage. The inner scales are thick, very juicy and crispy. Suitable for long-term storage, processing and fresh consumption. Lyubchik is a mid-early variety (85-100 days), recommended for growing as an annual crop from seeds and sets. The bulbs are dense, elongated-oval, weighing 100-150 g, semi-sharp taste. Dry scales are yellow, juicy scales are white, with green in the upper part. The variety is valued for its excellent taste. Suitable for long-term storage.
Fusarium bottom rot of onions
The disease is caused by a bacterium in the soil that affects the tops of the plant and leads to the death of the feather along the entire length, as well as to the rotting of the turnip, the bulb becomes softer and more watery, and characteristic rot of the bottom of the onion appears. The causes influencing the occurrence of the disease are:
- excess moisture in the soil;
- untimely harvesting;
- poor quality planting material;
- The growing season takes place in hot weather.
Carry out preventive measures while preparing the soil for planting. Use chemicals for soil treatment - 2% Iprodione (use according to instructions), TMTD fungicide will disinfect the soil and seeds, prepare a suspension in equal parts of water and the drug, not compatible with drugs containing copper. 0.5% copper sulfate disinfects the soil (dilute 50 g of the substance in 10 liters of water).
Follow the rules to prevent fusarium onion:
- disinfect planting material (potassium permanganate solution, Fitosporin);
- use early and early ripening onion varieties;
- treat the soil before planting (the techniques are listed above);
- alternate onion planting sites;
- loosen and weed the beds;
- harvest in a timely manner.
The disease may appear after harvesting and spread to healthy bulbs, observe storage conditions - place the onions in wooden boxes, the room must be ventilated, constant temperature +5 ° C, air humidity 60%.
Gray rot on onions
The infection persists well on planting material, infecting the soil and, accordingly, the entire crop through loosely closed scales. When you press on the turnip, the skin bends in the neck area, and a gray coating is visible on the surface.
The fight against the disease consists of the following measures:
- 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;
- proper collection of root crops;
- airing and drying the onions after assembly;
- creating conditions for storing crops;
- periodic bulkheading to remove rotten turnips.
Black rot on onions
Bulbs are affected by this disease mainly when stored improperly. Namely, high temperature and poor ventilation. First, the affected bulbs become soft, and then the scales dry out, the entire bulb mummifies and a black, dusty mass forms between the scales. The causative agent of aspargillosis is a very common mold that is transmitted both through direct contact and through the air. The most susceptible to this disease are unripe, thick-necked, poorly dried bulbs.
Control and prevention measures:
- thorough preparation of onions for storage (warming and drying at recommended temperatures);
- disinfection of onion storage premises;
- strict adherence to temperature and humidity storage conditions.
The best protection for onions from diseases and pests is to carry out preventive measures. The main thing is to know how to treat the onion before putting it in the ground. In order for the harvested crop to be stored as long as possible and not rot, it is necessary to dry it and store it in a room with good ventilation.
Powdery mildew on onions
Sometimes powdery mildew or downy mildew can spread to onion plantings. Such diseases must be combated immediately after their detection, since the onion affected by the fungus is no longer suitable for consumption. If there is powdery mildew in the garden bed, then at an advanced stage of the disease it can spread to other plants. Downy mildew is considered the most harmful and common disease that can affect varieties such as onion, batun, slime and set.
There are ways to protect onions, and gardeners should know how to protect their plantings. First of all, it is necessary to inspect the onions daily: their appearance can indicate the presence of powdery mildew. The onion feathers may become yellowish, stained or rusty. Powdery mildew can even attack perennial onion plantings. If it becomes noticeable that the onion is turning yellow, this is a possible sign of a fungal disease. To prevent rust from attacking, you need to treat the plants with anti-fungal preparations.
What to do and how to treat onions if they turn yellow
If the calendar shows August-September, then summer residents should not worry about the question of why the onions in the garden turn yellow. This is a natural process, the crop is ripe and will soon need to be harvested.
But if it’s the beginning of summer and the onions are turning yellow, then you need to decide what to water with in order to cope with this problem. After all, such a process is a serious problem that can leave gardeners without a harvest.
How to treat onions if they turn yellow due to pests
First you need to decide who got into it. It could be:
- onion fly;
- onion proboscis and thrips;
- stem nematode;
- onion moth.
A general tip to reduce exposure to all pests is that it should not be planted in the same bed every year. The minimum time it is advisable to keep a bed without onions is 4 years. Then it is more likely that it will not turn yellow due to pests remaining in the soil.
Treatment of plantings against onion flies, hoverflies and their larvae is carried out using the drugs Fufanon, Bazudin. Number of procedures – 2. To combat pests like onion moths, a working solution based on Iskra M is suitable. A solution of karbofos is used against caterpillars, the secretive proboscis, and its larvae. It is recommended to treat onions with a solution of colloidal sulfur against small pests. It is practically impossible to control them with standard fungicides.
Among the folk remedies for protecting culture, an infusion of tobacco and ground black pepper can be distinguished. It is prepared as follows:
- Steam 200 g of tobacco in 3 liters of water.
- After three days, add 1 tsp to the resulting infusion. black pepper and 1 tbsp. l. liquid soap.
- Add another 10 liters of water to the mixture and filter.
- The plants are sprayed.
Onion crops are characterized by good germination and rapid growth. However, the yield may decrease or even die due to diseases and pests. Timely prevention and compliance with planting technology significantly reduces risks. In this article we will examine the main questions of most gardeners: why the tips of the feathers of onions can turn yellow, what pests can spoil the harvest in spring or autumn. And also what to do and how to deal with adversity.
It is not difficult to plant and grow onions in a small plot or on a huge plantation., if you adhere to the technological process. However, in addition to the planned activities, there may be a need to treat the crop from pests and insects. You should not ignore signs of plant damage, because in just a few days the beds can thin out significantly. But it is quite difficult to cope with an advanced form of the disease or a mass infestation of insects; you cannot do without the use of chemistry. Therefore, it is recommended to include preventative procedures in your onion care schedule to prevent serious problems.
Downy mildew
Downy mildew is one of the types of fungal infection; the pathogen survives well on onion peels and seeds. The transition of bacteria to the active phase occurs when favorable conditions are created, which are characterized by high humidity and positive temperature conditions. The disease can be recognized by the following signs:
- the formation of yellowish-green oily spots on the surface of the leaves;
- a gray-violet coating settles under the feathers;
- increase in spot parameters;
- dying of leaves.
Control methods involve treating the crop and the soil underneath it with special or homemade solutions. Among the drugs that have proven themselves well are:
- Fitosporin-M for onions and garlic;
- Gamair;
- Planriz;
- Alirin-B;
- Glyocladin.
2-3 weeks before harvesting root crops, treatment with chemicals should be stopped. To protect plants from powdery mildew, it is recommended to continue spraying, but using folk remedies.
There are also traditional methods that most gardeners prefer:
- a solution of 9 liters of water, 1 liter of low-fat milk, 10 drops of iodine;
- a weak solution (slightly pink) of potassium permanganate;
- infusion of onion peel;
- a mixture of water (9 l) and whey (1 l);
- infusion of ash (half a bucket of ash for 8 liters of boiling water).
Powdery mildew on onions What does gray rot look like?
The infection persists well on planting material, infecting the soil and, accordingly, the entire crop through loosely closed scales. When you press on the turnip, the skin bends in the neck area, and a gray coating is visible on the surface.
The fight against the disease consists of the following measures:
- 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;
- proper collection of root crops;
- airing and drying the onions after assembly;
- creating conditions for storing crops;
- periodic bulkheading to remove rotten turnips.
Bacteriosis and its treatment with chemical and folk remedies
At high humidity, and in warm weather, putrefactive bacteria penetrate through the onion scales and infect a healthy fruit.
Rotting can occur directly in the soil, but most often bacteriosis occurs during crop storage. The fruits can be identified simply by their characteristic smell and swollen skin.
Remnants of last year’s fruits can provoke the appearance of harmful bacteria in the soil, so the beds must be dug up after harvesting. Onions are planted in an infected area no earlier than after 4 years.
Fusarium rot and how to get rid of it in spring and autumn
The disease is infectious; the pathogen is located in the soil, where infection occurs. During the development period, the bottoms of the turnips are affected by rot, as a result of which first the greenery dies, then the root part. Among the reasons that provoke the formation of a pathogen in the soil:
- waterlogging during irrigation;
- harvesting in rainy weather;
- late fruit harvesting;
- drought during turnip ripening.
- before planting, the seedlings must be disinfected;
- when choosing seeds, preference should be given to early and mid-ripening species (they are less susceptible to infection);
- observe watering norms, avoid waterlogging of the soil;
- Root crops should be collected in dry weather.
If an affected onion is identified, it should be removed from the garden bed and the soil should be treated with Bordeaux solution (1%).
Bacterial rot of onion seed
Rot often affects turnips when there is excess moisture in the soil. The reason is prolonged rains and the type of soil that prevents the rapid absorption of precipitation. Initially, mold forms in the neck area of the onion, descending over time through the seeds. Such a crop cannot be stored for a long time; the rotting process cannot be stopped.
Turnips are usually not used even for obtaining seeds; such material is affected by a fungus and is not capable of producing good seedlings.
- Before planting, the seedlings must be disinfected;
- Irrigation should be carried out under constant control of the degree of soil moisture;
- regularly clean the beds of affected plants;
- Harvesting should only be done 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
Not only diseases, but also various pests that prefer to colonize onions can reduce yields.
- Before planting, the sets should be prepared: warmed for several days at a temperature of 23-25°, soaked in a saline solution (1 liter of water per 1 tablespoon of salt) - 3 hours, then repeat the procedure, but in a manganese bath - 2 hours.
- Choose a well-ventilated place for the beds. It is recommended to place onions and carrots next to each other. For both crops, this will provide additional protection from pests.
- Change the location for planting onions every year. In late autumn, when frost sets in, you need to dig up the ground well so that harmful bacteria and larvae die.
If there is a massive invasion of flies on a plantation, it is unlikely that it will be possible to do without chemicals. Among the popular ones: Bazudin, Aktara, Muhoed.
In order not to use chemicals, many gardeners use traditional methods. The most effective are considered:
- a solution based on ammonia (for 10 liters of water take 3 drops of iodine, a tablespoon of ammonia, several crystals of potassium permanganate);
- tincture of fragrant herbs (add several branches of valerian, wormwood, mint to 10 liters of boiling water);
- pine decoction (half a bucket of spruce or pine needles is brewed in 10 liters of water);
- wood ash powder;
- powder of ash, red hot pepper, tobacco leaves.
In addition to the above methods, you can treat the bed with salt at the rate of 300 g of salt per bucket of water. The main thing that should not be forgotten when using this method is to spray the onions with clean water to wash off the salt from the feathers. If the treatment is successful, the flies will stop flying over the onions and will not lay eggs in the beds.
In addition, piperazine helps to cope well with the pest. Used at the rate of 1 package per bucket of water. It is necessary to spray all affected areas.
Pre-sowing treatment of onion sets against onion fly is carried out in early spring. You need to spray the entire garden bed. The zemlyan preparation also helps well in the fight against pests; you can always find out how to apply it in the instructions.
Onion mite and treatment against it
Before planting onions, the soil is fertilized. This is exactly the environment the tick chooses for itself. You can identify an insidious pest in a garden bed by its characteristic features:
- deformation of feathers with the formation of a white coating on them;
- wrinkling of the plant due to loss of moisture;
- formation of mold and mildew.
You should not use pesticides in the fight against ticks. The product is addictive to insects, so the treatment will be ineffective.
For pest prevention purposes, the following methods are used:
- careful sorting of seed during storage;
- preparing seedlings for planting (sorting and warming);
- carrying out disinfection procedures;
- regular treatment of beds with herbal decoctions and nettle infusion.
Onion thrips
To prevent thrips from settling in onion beds, it is recommended to carry out the following measures:
- change the location of planting onions in the garden annually;
- store planting material under proper conditions;
- follow the rules for preparing and planting seedlings;
- removal of all crops and tops from the garden bed;
- 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 traditional methods:
- placing sticky tape for flies between the beds as traps;
- planting a nearby onion plantation of fragrant herbs and marigold flowers;
- spraying with infusion of tobacco leaves (leaf for 3 hours);
- treatment of plants with infusion of celandine leaves (leave for 48 hours).
Reasons why onions turn yellow in the garden and what can be done
Yellow spots on winter onions do not always indicate the presence of diseases or pests. Sometimes the cause may be a lack of nitrogen in the soil. To correct the situation is quite simple - introduce nitrogen-containing fertilizers into the soil. For these purposes, organic and mineral baits can be used. You can also feed green vegetables with ammonia. It is an excellent fertilizer and also helps get rid of flies and other pests.
Watering with ammonium nitrate should be done with caution according to the instructions. In addition, you can water and spray the onions with kerosene. It allows you to protect the crop from onion flies. You need to process the bed using 2 tbsp. kerosene to a bucket of water. This measure will help preserve the harvest and there is no fear of re-infection.
Yellowed feathers may also indicate insufficient crop care. Each variety has its own growing characteristics. When planting different species, few people are interested in the intricacies of growing a particular hybrid. Experienced gardeners recommend that during the selection process you familiarize yourself 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 become deformed. Or, due to too hot summers under the influence of intense sunlight, feathers begin to dry out prematurely. In such cases, plants can be helped by covering them with film or agrofibre. Treatment in this case is not required. You need to fertilize the vegetable as usual.
Early diagnosis of the problem will help save not only the crop, but also prevent soil infection. There is no point in delaying treatment, because pests and diseases destroy plants very intensively.
Those that damage onions eat the bitter inner part of the crop, and it is not always possible to notice them immediately. As a result of such “raids”, the entire harvest can be lost. Fruits damaged by insects are exposed to soil microorganisms and rot. Let's look at the main and most common pests of onions and determine what methods are best to combat them in order to preserve your harvest as much as possible.
is a dangerous pest of onions. Significant damage is caused during the years of mass flight at the beginning of development and the period of onion growth. Crops sown with seeds for sowing suffer especially badly, because the larvae in dense stems crawl from the affected to the healthy. If onions are grown from sets and there is no need for thinning, then the risk of infection is minimal.
Onions infected with stem or neck rot are especially susceptible to attack by onion and sprout fly larvae. Usually in the middle and northwestern zone, under favorable weather conditions, it produces two generations, and in the southern regions it can produce three. Main signs of damage are the wilting of the plant in groups at the cotyledon and first leaf phases: larval tunnels appear in the bulb itself, and the larvae themselves live in the leaves and bases of the cotyledons. In an older plant, the neck of the bulb and the bulb itself are damaged, which causes the crop to wither and rot, and then die.
Regardless of where exactly the fly has penetrated, the onion will still die if the growing point is damaged by even one or two larvae. Description. An adult fly is light gray in color and has a body length of 6–8 mm. Wings with a yellowish tint, legs black. The male has a dark stripe along the abdomen and a row of setae on the hind tibia.
The eggs are elongated, white, 1.2 mm. The larvae are off-white, worm-shaped; back and abdomen rounded, narrowing at the anterior end, body up to 10 mm long; hook-shaped jaws. On the posterior segment there are two dark round plates with breathing holes. The fly's pupae are contained in a brownish-yellow pseudococoon.
The primary spring invasion occurs during the flowering period of lilacs. Reproduction occurs due to additional feeding with nectars during the week.
Females lay 5–20 eggs under lumps or between onion leaves. The egg laying period can last up to 1.5 months. Newly formed larvae gnaw through the neck of the leaves and penetrate into the flesh of the bulb itself, eating away its cavity, and then are able to migrate to other bulbs. Pupation of the larvae occurs after two weeks next to the damaged onion in the ground.
How to fight with onion pests in the form of flies :
Did you know? Research by scientists has proven that substances that are found in onions and can cause aroma, taste and tearing from its processing have a negative effect on cancer cells.
Description of the moth. The butterfly is small in size with brown front wings, the caterpillar is green-yellowish and covered with small short hairs. Butterflies, like pupae, overwinter on the remains of onions, in sheds, and greenhouses. Eggs are laid in June on the back of a leaf, bulb or flower arrow.
Causing harm. After seven days, the larvae mature and eat the pulp of the leaves, leaving the outside skin untouched. The caterpillar penetrates the bulb or neck and can even damage the inflorescences. Pupation of caterpillars occurs on onion leaves in the first period of June: in the soil, on weeds, and plant debris. After two weeks, butterflies form. The caterpillar is capable of causing damage to the onion throughout the entire growth period, since it can produce two or even three generations over the summer.
Control measures:
Onion pests in the form of moths are very dangerous for the crop, so there are also many types of fight against them using folk remedies: - infusion of ash - pour boiling water over 300 g of ash, set aside, strain, add 40 g of liquid soap;
- garlic infusion - mince a large amount of garlic, add water at a ratio of 1:1. Infuse in a warm place for at least a week in a tightly closed container. This infusion is called mother infusion and can be stored for a very long time. Treat with a solution: 70 g of infusion per bucket of water;
- tobacco infusion - 200 g of raw tobacco + 1 tablespoon of soap, pour hot boiled water. After it has cooled, strain through cheesecloth and treat the onion, and especially the soil around it, at the rate of 1 liter per square meter;
- infusion based on red capsicum - boil 1 kg of pepper, cut in half, in a saucepan with 10 liters of water, strain after cooling. Processing is carried out at the rate of 130 g of concentrate per bucket of water + 40 g of soap. The concentrate itself should be bottled and stored in a cool, dark place.
The hoverfly is an infrequent pest guest, but no less harmful than a fly. It usually appears on onions and causes damage in the second half of the growing season.
Damage manifested by stunting and yellowing of leaves, and then their wilting. The bulb becomes soft and acquires an unpleasant specific odor. If one bulb is attacked by a group of root beetles, it turns into a black putrid mass.
Description. Stocky flies of medium size. The female (up to 7 mm) is slightly larger than the male (up to 6 mm). Female hoverflies have a flat abdomen, while males have a slightly swollen apex. The body is bronze-green, and the back has two light gray stripes. Black mustache. The abdomen can be blue or green. The paws are brown-black or simply black. Females lay eggs on already weakened plants that can be damaged by other pests. Laying is carried out in small groups, one female brings up to 100 eggs. Control measures the same as with the onion fly.
Did you know? The composition of natural sugar in onions is much higher than in pears and apples. One onion contains up to 6% sugar. When fried, caustic substances evaporate and the onion becomes sweet.
Onions are a favorite treat of tobacco thrips. This pest causes damage to both the bulb itself and the leaves. During the wintering period it lurks in dry onion scales and reduces the quality of the vegetable.
Damages fleshy scales, which become rough and then dry out completely. Whitish stripes and dark dots appear on the leaf (thrips feces). Leaves that are severely affected completely change their color to whitish, become distorted and dry out. Onion growth stops and the seeds are mostly unsuitable for sowing. The adult has an elongated shape with narrow wings that are folded along the entire body. The body is 1–1.5 mm, has a general yellowish color. The antennae are yellow, the eyes are red. The short forewings are darker in tone than the long hind wings.
The eggs are white, kidney-shaped. The larva has two growth stages. In the first, the light-colored larva feeds on the plant; as it grows, the yellow-green intestine becomes visible on the abdomen. At the second stage, it does not feed on onions, but is in the ground. It overwinters in dry onion leaves in storage, or under a layer of soil on the planting site.
The female brings up to 100 eggs, which she places one at a time in the leaf tissue under the skin. After just 3–7 days, the larvae appear. Generational development in warm areas reaches 2–4 weeks.
It’s not difficult to identify them on onions, but not everyone knows how to deal with them, because not all chemicals affect them. Experienced gardeners have proven themselves to be the most effective in practice:
Important! Two treatments close in time should be observed with an interval of no more than 7 days. The reason for this is that eggs and nymphs are highly resistant to drugs, or the drug may not immediately reach them.
Causes damage in patches. In the southern zone it can give two generations, and in the middle zones it usually gives one. Onion rattle can often be confused with lily rattle; their only difference is that lily has black legs and a head, and onion has red ones.
Damages onions, gnawing through holes, resulting in the leaves breaking. An adult is able to penetrate inside the tubular leaf.
Description. The bugs are completely bright red, only the tip of the abdomen is black, 6 mm in length. The eggs are 1 mm long, orange, smooth. The larva is six-legged, has black dots on its sides, and is off-white in color. The paws, head and chest shield are black. A brown mass forms around the larva due to the fact that it covers itself with excrement.
How to treat onions against these pests:
To combat rattles, use drugs used in systems for integrated management of the number of phytophages - “Proclaim”, “Spintor” (use according to the instructions). 
Description. Bug up to 3 mm long. At the end of the head there is a “proboscis”, bent down. The antennae are club-shaped, thickened at the end, and geniculate. The body is black, but due to the white scales it appears gray. There is a white stripe along the suprawing suture. Paws are red-brown.
The eggs are white, round, small - up to 0.5 mm. The female lays them in April, and within two weeks the larvae appear, which can damage 100% of the onion leaves. One leaf can contain from 7 to 17 larvae. The larvae are yellow, with a brown head, without legs, up to 7 mm. Then the larva gnaws its way into the bulb through the leaves, and emerges from it into the ground and begins to pupate. The larval development stage lasts up to one month. The bug overwinters in lumps of soil and under dried grass. Wakes up in early spring. 
Damages initially diseased sprouted bulbs that were not removed from the site, then moves on to new crops. It pierces onion leaves with its nose and feeds on the pulp. Affected leaves develop whitish round spots that look like needle pricks. Then the leaves dry out and the plant dies. Onion crops planted with seeds suffer catastrophically.
The most effective protection from is regular loosening of the soil in order to break up the “earthen cradles” of the pupae and the wintering grounds of the bug itself.
Extremely dangerous for onions; in very contaminated areas, complete destruction of the crop was observed.
Description. The stem nematode is a thread-like small worm, its structure can be seen using a microscope, its length is up to 1.5 mm and its width is 0.04 mm. The ends of the body have narrowings, and in the mouth there is a needle-shaped stylet (hollow, passing into the esophagus), thanks to which it is able to suck juice from plants. At the base the stiletto has three swellings similar to a ball. Eggs are not visible to the naked eye and their sizes are measured in microns.
It can overwinter in the soil, in the onion itself and its seeds. In dried plants it remains viable for up to five years, and when placed in a humid environment it regains its vital activity.
Causing harm. It gets into the onion both through the leaves and through the bulb itself from the bottom. During the larval stage and in the adult worm phase, it feeds on plants. Egg deposition also occurs in onion tissues. Damage is caused to the plant as soon as it begins to grow.
Damaged Bow in the early growth phase it has a flaccid appearance, and the affected areas are distinguished by thinner areas. When infected later in the growing season, onions may have a healthy appearance, sometimes distinguished by the appearance of white spots. But inside it is loose, the scales do not fit tightly to each other, the grainy structure of the fleshy scales appears, in the affected areas it is more refined and pigmented with white and brown spots. The onion may crack and the inner scales may bulge outward. Such a plant rots at high humidity, or dries out quickly at low humidity. 
The nematode usually attacks in mid-summer. How to treat onions against pests such as nematode worms is a complex question, because fighting a nematode rarely leads to its complete destruction. Drugs that can destroy it are very toxic to the plant itself. The main principle of nematode removal is prevention:
- do not plant plants that are susceptible to nematode invasion in the same place for several years in a row;
- during harvesting, carefully select the seed onions and repeat it in the spring before planting;
- carry out deep loosening of the soil at the planting site;
- Before planting onions in the ground, add contact poisons in small doses.
The nematode does not tolerate temperatures above 40 °C, so an effective method of control before planting is to soak the onion sets in water up to 55 °C for 15–20 minutes. This method will not harm the crop, but will kill the nematode.
Did you know? Fresh onion juice is very nutritious and healthy, perhaps for these reasons it attracts various pests.
Most often, onions are intensively affected during storage. It often enters the bulb from the bottom, but it can also penetrate through damage caused by other pests. It settles between the scales of the onion, and it gradually begins to rot.
Description of the pest. The female is up to 0.2 mm long, has an elongated body, is white, has two pairs of legs, which are located in the front of the body. Shield without visor, semicircular. The skin has annular grooves: dorsal - up to 87, ventral - up to 76. The larvae are smaller in size and have fewer rings. They lay one egg per day, 1 female can lay up to 25 eggs. Ripening occurs in three days at temperatures above 10 °C. In cold conditions they slow down their vital activity, when favorable they multiply, and at temperatures above 18 °C they are spread to other bulbs.
Signs habitat in onions. Yellow or green pigmentation appears on the inner scales. When drying during storage, the pigments are more noticeable. During the growing season, the leaves turn yellow, curl, look as if they are affected by chlorosis, and are stunted in growth.
basis struggle is prevention:
Scoops
There are leaf-gnawers and gnawing ones. The first ones feed on the tops, and the second ones are in the ground and gnaw the bulb itself. Usually they are active at night, and during the day they are in a phase of immobility.
Description. The adult individual is represented by a butterfly with a wingspan of up to 5 cm. The front wings are brown with transverse white stripes, and the hind wings are light brown.
The eggs are dark gray. hemispherical. One butterfly can lay up to 40 eggs. The larva appears after 12 days. Larva: green caterpillar on the sides with yellow stripes, sometimes gray-green or yellow-green. In warm regions it produces two generations. 
Damage. The larvae crawl and gnaw leaves, and are able to bite into the bulb itself. Damaged onions emit an unpleasant odor and rot.
Struggle:
Onion pests cause great damage, and the fight against them lasts for many centuries, so there are many folk remedies. One of them is treatment with a solution of wormwood during its flowering period: 300 g of crushed wormwood per 1 cup of wood ash and a tablespoon of ground soap, pour 10 liters of boiling water, cover with a lid and leave for one week. Spray after the settling period has expired. shallot aphid
Description. The body is brown in color, ovoid in shape. Larvae are dark shades of yellow or green. The eyes are brownish-black. Developed antennal tubercles, converging in front and longer than the body. The Spitz has the sixth segment and segments 4–5 black, and the rest are the same color as the body. The tubes are light, cylindrical, tapering towards the apex, ending in a dark funnel. The tubes are 8 times thicker than their length.
Signs of damage. The leaves fade, bend, and the crop lags behind in growth. The leaf feather that goes to the greens becomes contaminated with aphid feces and skins that the larva sheds. It is located on the leaves, under the outer shell of the onion.
Main protective measures are agricultural techniques:
By following some tips, you can prevent onions from becoming infested with pests.
- Compliance with crop rotation (plant onions in their original place no earlier than after 5 years).
- Carrying out sowing on time with zoned varieties.
- Autumn and spring digging of the landing site.
- Disinfection with a solution of copper sulfate before planting.
- Maintain distance between crops during planting for good ventilation.
- Timely removal of weeds.
- Treatment with biological products during the germination and feather ejection phases.
- Checking and processing planting material before planting.
- Identification and destruction of infected plants.
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Onion diseases and treatment - how to fight quickly and effectively?
Particular attention should be paid to onion diseases, descriptions and their treatment, because it is not always possible to preserve the harvest until next spring. Downy mildew, rust, fusarium rot, neck rot of the bottom, wet bacterial and black, green mold rot, as well as mosaic are the ailments that are most often encountered and the main question is how to deal with the scourge, what folk remedies and chemicals to use, read more in article...
Onion disease - pictured
Downy mildew or powdery mildew
A common fungal disease of the plant is considered to be downy mildew, the causative agent of the infectious process is conidia. This is a spore that causes light green or yellow spots to appear on the stem during the vegetative growth of the plant. In sunlight in the morning, you can observe the presence of a grayish-purple fungal coating, which is why the plant appears dirty. Remember, the disease is spread by insects, humans, wind and rain. Causes of the disease:
- high air humidity (95%) at a temperature of +15° C
- abundance of weeds
- evening and frequent watering
- was not carried out
How to treat onion peronosporosis, how to fight it? There are quite a few ways, but the greatest positive effect is achieved if drugs against peronosporosis are used:
- suspension Polycarbacin
- 1% Bordeaux mixture
- Ridomil Gold
downy mildew of onion - in the photo
We prepare the first two like this - dilute 40 g of the drug per 10 liters of liquid and spray the stems two or three times at intervals of 10-12 days. Polycarbacin does not leave burns on the leaves of the plant and is low-toxic, but the last treatment should be carried out no later than 20 days before harvesting the onion. In addition, onions treated with Polycarbacin cannot be cut into feathers.
You can make 1% Bordeaux mixture by adding 100 grams of copper sulfate and 100-150 grams of slaked lime to 10 liters of water. Ridomil Gold should be used in several stages - when the first warm days of April appear, and in May, when powdery mildew is most likely to appear, for preparation, dilute 25 g in a bucket of water.
Downy mildew of onion, folk control measures:
- Chop any weeds growing in the garden and fill a bucket halfway with them, add hot water + 60 ° ... + 70 ° C, let it brew for 2 days, strain and spray onion
- Pour onion peel (250 g) into 10 liters of water, boil, let it brew for 2 days, and treat the plantings at intervals of 7-10 days
- Pollinate the beds with wood ash at the rate of 50 g per 1 m²
downy mildew - pictured
Follow safety precautions when using fungicides and remember to wash the product before use. Prevention of peronosporosis:
- process planting material
- remove weeds and plant debris
- remove fallen stems
- plant onions in a warm and ventilated area
Onion rust
The disease is caused by a fungus that spreads well in a humid environment and affects the stem and growth of turnips, so it is advisable to eradicate it immediately. The disease, onion rust, is expressed by bright orange-yellow swollen spots, round in shape, which then turn into black dots. The reasons for the appearance include early planting, densely planted beds, an abundance of weeds and excessive watering.
It is worth noting that the fungus only eats into a wet leaf; it will not penetrate into a dry feather. If onion plantings are exposed to rain for a long time, fungal spores quickly germinate and take root. If the onion is sick, most likely other shrubs will be affected by the disease. Due to the fact that diseased feathers do not work well, the yield is reduced.
rust using garlic as an example - in the photo
Prevention of the disease:
- treat planting material with bactericidal agents (for example, potassium permanganate solution)
- plant varieties resistant to the disease (Sprinter)
- fight weeds and remove plant debris from the beds
- cut off damaged stems and burn
- do not plant onions too thickly
During the period of massive growth, onions should be sprayed with copper oxychloride. To prepare the solution, take 30 grams of the substance, the same amount of liquid soap and dissolve it all in a bucket of water. The treatment must be repeated after 7-10 days. It is better to carry out processing during the day so that the feather has time to dry. Hom, Tilt and even furatsilin cope well with rust (10 tablets need to be diluted in a liter of water).
Onion rust appears at the end of April; if you notice the first signs of the disease, stop watering the plant and fertilizing it with nitrogen fertilizers, and get rid of damaged stems. Perennial onion species are most susceptible to the disease, and their treatment is also urgent.
Fusarium bottom rot
The disease is caused by a bacterium in the soil that affects the tops of the plant and leads to the death of the feather along the entire length, as well as to the rotting of the turnip, the bulb becomes softer and more watery, and characteristic rot of the bottom of the onion appears. The causes influencing the occurrence of the disease are:
- excess moisture in the soil
- late harvest
- the growing season takes place in hot weather
onion fusarium - in the photo
Carry out preventive measures while preparing the soil for planting. Use chemicals for soil treatment - 2% Iprodione (use according to instructions), TMTD fungicide will disinfect the soil and seeds, prepare a suspension in equal parts of water and the drug, not compatible with drugs containing copper. 0.5% disinfects the soil (dilute 50 g of the substance in 10 liters of water).
Follow the rules to prevent fusarium onion:
- disinfect planting material (potassium permanganate solution, Fitosporin)
- use early and early ripening onion varieties
- treat the soil before planting (the techniques are listed above)
- alternate onion planting sites
- loosen and weed the beds
- harvest in a timely manner
The disease may appear after harvesting and spread to healthy bulbs, observe storage conditions - place the onions in wooden boxes, the room must be ventilated, constant temperature +5 ° C, air humidity 60%.
Neck rot of onions
The disease is caused by a fungus that develops in unharvested, rotting plants in the garden, manifested by yellowing of the onion neck and subsequent spread to the plant’s bulb to the bottom. An unpleasant odor appears in the harvested crop, the head is loose, and when the bulb is cut, dark areas are visible at the base, sides or neck of the vegetable. Causes of the disease:
Neck rot of onions - pictured
- excessive moisture and lack of sun
- poor quality planting material
- insufficient disinfestation of soil and raw materials
- harvesting onions in rainy weather
- insufficient feeding of the plant
At the first suspicion of a disease, you can use 1% Bordeaux mixture (dilute 100 g of the mixture in 10 liters). The drug Quadris is used both in the treatment of planting material and for the treatment of fungal diseases in the garden. Preparation: dilute 8 ml of the drug in 10 liters of water. Prevention of the appearance of cervical rot:
- weed cutting
- loosening the soil
- harvesting ripe crops in dry weather
- drying the bulbs for 7 days at +35° C (after collection)
- storage in a disinfected room at +3° C and humidity not higher than 70%
Wet bacterial rot and black rot
Caused by bacteria that damage an already harvested crop, but sometimes the plant becomes infected in the soil. Externally, the onion peel looks wet, then the inside becomes loose, sticky to the touch when pressed, moisture with an unpleasant odor is released.
Reasons for appearance:
- increased soil moisture
- contaminated soil
- incorrect storage conditions
- crop damaged during harvest and by insects
black rot of onions - in the photo
Prevention:
- disinfection of planting material and soil
- fight against onion fly, the vector of the disease
- maintaining the integrity of the onion head
- harvesting in dry weather
- drying bulbs
- compliance with storage rules (listed above)
To save the harvest in a rainy summer, experienced summer residents and gardeners recommend trampling onions before harvesting. Why, you ask? To ensure that the bulbs do not become saturated with excess moisture and have the opportunity to ripen by that time,. If you pull out an onion, you will see that it is growing and is not going to ripen, while the feathers are green. So, two weeks before the expected harvest, walk along the bed and trample the onion in the neck area. Don't break it, just press it well to start the ripening process. After 14 days, your onion can be removed from the garden and not be afraid that it will rot.
Mosaic bow
The causative agent is a virus that infects the bulb and feather itself, expressed by the presence of light yellow spots, light green longitudinal lines on the stem, as well as curling and drying of the edge of the green part. The disease is serious, it affects and therefore treatment must be carried out. The main sign of the appearance of a mosaic is considered to be different lengths of onion leaves, in other words, crumpledness, while the turnip does not develop.
bow mosaic - pictured
The reasons for the appearance are considered to be late planting, densely planted beds, and lack of control of aphids. Use insecticides for onions to eliminate aphids - Aktara affects the plant itself from the inside - dilute 8 g of the drug in 10 liters of water, if you have liquid, then 2 ml per 10 liters and water the beds. If you don’t want to use insecticides, prepare a wood ash tincture - boil 10 liters of water with 300 grams of wood ash for 30 minutes, let it cool and add 40 grams of grated laundry soap. Now you can spray the beds.
Prevention of onion mosaic is as follows:
- maintain crop rotation
- fight weeds
- follow the watering schedule
- fight insects
Green moldy rot
The causative agent is a fungus that infects vegetables during storage, expressed by drying out of onion skins and the appearance of green (penicillium) mold on the bottom and side parts of turnips, most often appearing after the second or third month of storage. Causes of green moldy rot:
- mechanical damage during harvest
- high humidity in the room where onions are stored
Harvest carefully to avoid damaging the bulbs. You can use preparations against small pests (mice) to keep the vegetables intact. Maintain a temperature of +3° C and a humidity of 60% in the room where the onions are stored.
Now you know the most common onion diseases, descriptions and their treatment, good harvests to you!