Who is the onion crypto-hunter, pest control measures

Onion is an undemanding vegetable, it grows in any weather conditions and soil composition. The only things that threaten the crop are diseases and pests. Various insects feed on green shoots, and their offspring penetrates the bulbs. Sensible damage to the crop is inflicted by the onion crypto. The beetle proboscis punctures a hole in the stems, and its larvae eat out the flesh of the ground part. The pest settles in any onion crops - batun, shallots, chives.

Appearance of a secretive hunter

Weevils or elephants, which include the onion cryptocephalus, have about 50 thousand species, 7 thousand are found in Russia. A representative of the weevil genus has an oval convex body of black or gray color. The size of the pest is 2-2.7 mm, the organ of food is the proboscis or the rostrum. Most of the time, the bug bends it down. Cranked antennae terminate with maces, they are located at the base of the rostrum. Rigid elytra tightly fit to the body, outside they are covered with grooves. Thin black limbs are covered with white hairs. Having studied the photo of the onion crypto-venom, it is easy to identify the pest.

Insects show sexual dimorphism - males are smaller than females, they have a shorter proboscis, and antennae are located closer to the head. Insects differ in the structure of the genital organs.

The female lays round white eggs in green shoots of onions. Their size does not exceed 0.5 mm. One egg is laid at a time, 50-60 pieces per season. After one to two weeks, a legless larva appears. Its length is 6 mm, in one leaf there can be 5-10 insects. The larvae are yellowish, the body is curved, and the head is brown. They gnaw passages inside the pulp of leaves. From the outside, these lesions look like light strokes.
Under the influence of pests, green shoots turn yellow and deteriorate. After 14-20 days, the larvae gnaw through the leaf and go into the soil. In the earth they turn into a chrysalis. At this stage, the offspring resembles an adult weevil. The pupa has the rudiments of legs, wings, and proboscis. At the end of June, a new generation of beetles appears.

Attention. The crypto-scavenger is distributed throughout the European part of Russia and is found in Siberia, Kazakhstan and North America.

Onion Crypto-Hunter Life Cycle

Beetles hibernate at the adult stage. Colds survive under the turf, old grass, hide in the soil. Favorite places are slopes of ditches, ravines, roadsides. They appear early on the surface - in April-May. The diapause period ends when the earth warms up to 10⁰. At first, they eat last year's sprouted onions, which remain in the fields and in the gardens. Then they move to young shoots. A large number of insects can bring larvae to 80-90% of planted onions. Beetles are active in the evening, she prefer a hidden lifestyle. If the weevil is disturbed, it immediately runs away and hides.

Attention. At the end of June, the larvae of the crypto-angler leave onion leaves for pupation in the soil.After this, new leaves grow in the crop, although the initial damage negatively affects yield.

Stealthy hunters reach puberty in the second decade of May. After mating, the female lays eggs on the inside of the onion leaves. The ovipositor lasts 2-3 weeks, up to 10 larvae can appear inside one green feather. The development of offspring from an egg to an adult larva takes about 1 month. Then the insect leaves the ground part of the onion and burrows itself into the soil. In the ground at a depth of 3-4 cm, the larva sets up a cradle, where it turns into a chrysalis. After 2 weeks, young weevils appear.

In July, the second generation of beetles appears. They also eat onion leaves. By this time, the plant begins to bloom. Secretive-minded people climb on inflorescences, gnaw pedicels. Pests provoke the death of onion seeds. In the autumn, after collecting the vegetable crop, the beetles fly away for wintering. In search of convenient and safe places, they fly 200-300 m. The lifespan of an onion crypto-hunter is 1 year.

Information. Adult stealthworms sometimes feed on garlic leaves, but the larvae live only onions.

How to deal with a pest

Comprehensive measures to combat the invasion of the onion crypto-hunter include:

• mechanical removal of damaged leaves;
• agricultural activities;
• the use of insecticides;
• safe folk recipes.

The main harm to onion crops is caused by larvae; the nutrition of adults has less noticeable consequences. With a regular inspection of onion beds, it is easy to notice the specific damage caused by the pest. These are white spots in places of puncture with a proboscis and light lines on the leaves. They are left by larvae crawling from the inside of the green feather. Insects inflict the most harm on a batu-onion grown for the sake of lush greens. Having found leaves with traces of pest infection, they must be removed and burned.

Agrotechnical methods

It is extremely undesirable to use chemicals to exterminate pests onions. This method is resorted to in exceptional cases. The main front of the fight against the weevil beetle is agrotechnical measures. The following actions are recommended for the destruction of the crypto-hunter and the prevention of its appearance on onion beds:

1. Alternate planting of vegetables in one bed. Proper crop rotation will deprive the pest of habitual food.
2. After harvesting, carefully destroy the remains of plants. Harvesting old bulbs and husks will deprive the crypto-venom of food sources in early spring.
3. In June, when the larvae of the crypto-angler pupate in the soil, it is necessary to carry out cultivation more often. This procedure helps to destroy insects by destroying their earthen cradles.
4. In late autumn, it is worth digging up the supposed places of beetles wintering - slopes, roadsides. Hidden insects will be on the surface and die from frost.

Folk recipes

Do not rush to the store for chemicals to destroy the onion secretive hunter. You can find safe products in the kitchen or pharmacy. Weevils, like other insects, have their own taste preferences and antipathies. They do not like hot spices - pepper and mustard. A mixture of red pepper and dry mustard scattered along the aisle helps to scare away the beetles from the beds.

Another recipe that pests will not like is ash and tobacco dust. The ingredients are mixed in a 2: 1 ratio. Ash is collected after burning branches, boards and other wooden trash. Dry tobacco leaves are crushed into dust. After mixing the two components, sprinkle the aisles.

Tip. So that the mixtures repelling insects are not blown away by the wind, they are scattered on moist ground. A good moment for making the composition is loosening the soil. In this case, the components penetrate into the ground, where pupae and young beetles are located.

Dry herbs also help in the fight against the onion crypto-hunter.If tansy and celandine are growing on the site, then they can be dried and prepared for future use independently. Otherwise, these plants are bought at the pharmacy. The products are sold dry, so they are immediately ready for use. Two herbs are taken in equal amounts and chopped. The resulting dust scatters in the area where pests are noticed.

An equally effective method is spraying with infusion of potato or tomato tops. These compounds scare away many insects, while absolutely safe for humans. To prepare a substitute for chemical insecticides, 1-2 kg of plants per 10 liters of water will be required. Finely cut the tops and pour boiling water, insist 4 hours. Filter. The infusion is ready.

Tip. Experienced gardeners set up a peculiar trap in the middle of the garden for secretive hunters. Insects prefer to settle on the variety of onion-batun. Among onions, a row of this variety is specially planted. Pests are moving on him. The main thing is to cut off leaves with larvae in time, preventing their distribution.

Chemicals

Treatment with the insecticidal agent “Karbofos”, “Karate” and “Decis” is possible during the growing season. It is carried out in two stages, so that the action of the drug captures pests after changing the stage of development.

Attention. If the green leaves of onions are eaten, then they absolutely can not be sprayed with insecticides.

An onion crypto-hunter can be destroyed without chemical treatments. It is enough to follow the recommended agrotechnical measures.