How to deal with onion fly folk and chemical means?
When an onion fly appears, the appearance of the plant changes in order not to lose the crop, you need to know how to deal with it. It will not hurt every gardener to get acquainted with the description of the pest and the main reasons for its appearance in the garden.
Biological portrait
The onion fly is a common vegetable pest. The larvae of these insects penetrate into the bulb from the inside or from the bottom side. The larvae of the first generation are especially dangerous. Damaged onions begin to wither and rot.
Appearance
An onion fly can be easily confused with a common fly, house fly, or cabbage fly. It is important for vegetable growers to know what a fly looks like in order to start fighting in the early stages of its appearance. The onion fly is gray-yellow in color, with an average length of 7–8 mm. Vertical stripes can be seen on the wings.
The eggs laid by the insect are white, oval in shape, 1 mm long with a longitudinal stripe in the middle. Under favorable conditions, the larvae begin to appear already on the 4th day.
The transparent white larvae are small in size, about 1 mm. The back of the body is thicker than the front. After three weeks, the larva turns into an adult.
The flies themselves do not harm the plants, but they constantly lay new eggs. You need to be afraid of the larvae that hatch from them. Control methods should be aimed at both the adult insect and their larvae.
Reproduction
The onion fly starts flying at the end of April with the onset of warmth. At the same time, it begins to actively reproduce. Years take quite a long period of time, about 50 days. Lays eggs directly in the soil or remnants of dry husks in the beds where onions or garlic grow. Less often it lays eggs in the axils of the leaves and on the leaves themselves.
One adult insect can lay up to 60 eggs in its entire life. To lay eggs, an adult needs additional nutrition in the form of nectar and pollen from flowering plants.
Onion fly larvae that emerge from eggs are kept in groups and are capable of destroying the entire interior of the bulb. Easily gnawing through the peel of the turnip, they penetrate inside. After 3 weeks, the larvae burrow into the soil and pupate. And after another 2-3 weeks, a new, young generation of pests appears.
A trail of rot on the bulb should be the reason for the start of the fight against the pest. Carry out preventive treatment of healthy plants and treatment of bulbs already infected with pests.
Signs of the presence of a pest
The larvae of adult insects suck all the juices from the bulb and devour the pulp. After three weeks, the flies completely destroy the plant, burrow into the soil and pupate. She spends the whole winter in this state.
In spring, the onion fly emerges from its cocoon, weak but capable of life. For a week she will feed on the nectar of dandelions or lilacs, and in another week the sexually mature period will come. At this time, insects move to the onion beds.
The following signs will help to notice pests on the vegetable garden in time:
- The bulbs begin to rot and give off an unpleasant odor. In the section, you can see the moves made by the larvae.
- The plant slows down in growth, the feathers begin to turn yellow, wither, the tips curl inward.
- The bulb is easily pulled out of the soil from the root; near the bottom you can see small worms, these are the fly larvae.
After harvesting, you need to dig deep into the ground (to a depth of 20 cm). How can pest infested soil be treated? The onion fly dies in a salty environment, so it is recommended to water the beds with a saline solution before planting the bulbs. The larvae die immediately.
How to get rid of an onion fly?
If preventive methods did not help, and the fly still appeared, you need to take decisive measures to combat. Folk remedies and chemicals can be used to combat the pest.
Folk recipes will help answer the question of how to effectively deal with an onion fly. The composition contains components that are available in every home and are absolutely safe for cultivated plants.
In the case when individuals have multiplied to a large number, chemicals must be used against the parasite. They should not be used too often, as pesticides accumulate in the head and cause harm to human health when eaten.
Folk remedies
Since onion turnip quickly absorbs insecticides, experts recommend using folk remedies for onion flies.
One of the proven and effective methods of dealing with onion fly is a solution that contains kerosene. Before processing with kerosene, the soil is thoroughly watered with plain water. Then water the bed with a solution. For 10 liters of water, take 30 ml of the substance.
Tobacco dust is used against pests. The solution is easy to prepare. You need to take 200 g of tobacco dust, which is diluted in 10 liters of hot water. To increase efficiency, add 30 g of soap (liquid or dry) to the composition. After that, the solution is left to infuse for 2-3 days. You can simply sprinkle tobacco dust on the garden bed. You can pre-mix it with lime.
If pests are found on onion beds, gardeners recommend watering them with saline. Dissolve 300 g of salt in a bucket of water. When watering, make sure that the solution does not get on the feathers. After two weeks, watering is repeated, but with a more concentrated solution.
A mixture of ash with dry mustard, ground pepper or tobacco dust helps to cope with the problem. Treatment of beds with a similar composition should be carried out 3-4 times with an interval of 7-10 days.
Deep digging of soil also helps to cope with the problem. The larvae that hit the surface of the earth quickly die.
Chemical fight
You can process onions with ammonia... Three drops of iodine, a drop of potassium permanganate, 2.5 ml of boric acid and 30 ml of technical ammonia are dissolved in a bucket of water. The water needs to smell slightly like ammonia. It is recommended to water each affected bush with the resulting solution (about 250 ml of solution is consumed for each root).
It is advisable to carry out the treatment with ammonia in the evening so that the soil retains moisture longer. It is better to water between rows, avoiding direct contact with the root.
After processing, it is recommended to loosen the soil so that the smell further scares off pests.
In critical situations, chemical agents such as Aktara, Intavir, Metronidazole, Fitoverm, Creolin, Zemlin will help to save the crop.
More recently, a solution based on Metronidazole has become popular among gardeners. For 10 liters of water, take 5-6 tablets, which must first be crushed to powder. It is allowed to water with a similar solution 1-2 times for the entire period of plant development. During watering, avoid getting the drug on the leaves.
Prevention
The first signs of the presence of a pest in the garden can be seen in the spring, when dandelions, cherries and lilacs begin to bloom. Flowers are essential for the development of insects. The fly feeds on the nectar of these plants.
The appearance of a pest is easier to prevent than to look for ways to fight it later.
Preventive protection against an onion fly can include a number of the following:
- it is better to plant onions next to a carrot or tomato bed (the fly cannot stand the smell of carrots and tries not to lay eggs next to this vegetable);
- onions should be planted as early as possible;
- it is impossible to plant onions in the same place for several years in a row (pests successfully winter in the soil, burrowing into the remains of plants);
- it is recommended to mulch the soil (you can use rotted manure, hay, peat as mulch);
- planting material must be placed in a disinfecting solution (a weak solution of potassium permanganate is suitable);
- before planting, it is necessary to fertilize the soil with peat or manure;
- the ground can be pretreated with saline, and after 5 hours it can be well shed with clean water;
- after emergence, it is useful to carry out preventive treatment with a bitter solution based on, for example, wormwood, pepper, tansy;
- after harvesting, you need to dig up the ground, the larvae on the soil surface do not tolerate cold weather and die.
It should be remembered that before using any solution, the soil must be watered! This will allow all components to operate safely and effectively. Some solutions require watering with clean water several hours after the procedure.
For the entire growing season, the onion bed must be properly and carefully looked after: weed on time, avoiding the growth of weeds, observe the correct watering regime and be sure to loosen the soil.
