Leek and leek maggot are extremely harmful, what are the comprehensive control technologies of leek

Proper fertilization. The fertilization of leeks should be mainly organic fertilizer, supplemented by chemical fertilizer, and should be fertilized with nitrogen, phosphorus and potassium balance. Organic fertilizers, especially cake fertilizers, should be fully decomposed before being used to prevent the aggravation of leek maggots; Chemical fertilizer should be applied according to the soil fertility nitrogen, phosphorus and potassium, and trace element fertilizer should be appropriately supplemented to prevent excessive nitrogen fertilizer, so as not to cause plant growth.

Spring pesticide. In early spring, when the soil begins to thaw, the topsoil around the leek roots is removed with a bamboo skewer to expose the leek maggots to the ground and die naturally once they are exposed to low temperatures and dry air. Irrigation to kill insects.

When the larvae of leek maggots occur in spring and autumn, the root system of open-field leeks was continuously watered and flooded for 2 to 3 days. The arched leeks are irrigated in late November and early March of the following year. In the field where the leek maggot occurs severely, irrigation should flood the back of the furrow, which can significantly reduce the damage. Dig the soil and dry the roots.

During the growth period of leeks, the topsoil is removed, and the "leek core" is exposed to dry for 5 7 days, which can kill part of the leek maggots.

You can spray some insecticides, so that you can kill all the small insects, or you can move them to a wider place to keep enough sunlight, and you should also increase the distance between them, not too close, only in this way will not produce small insects.

First of all, when planting, we must choose the soil is more fertile and wide land, and use farmhouse fertilizer, do not use fertilizer bought outside, water the plants more, but also to prevent the occurrence of pests and diseases, if there is a situation of small insects, then we must spray insecticides in time.

First of all, it is necessary to ventilate in time, and it is necessary to prune off these rotten leaves in time, and to ensure the amount of watering and fertilization.

That is, when choosing seeds, it is necessary to choose good quality and strong disease resistance, and then in the process of planting, proper watering, proper fertilization, timely prevention of pests and diseases, timely spraying of pesticides.

<> leek maggot, scientific name leek late-eyed mushroom mosquito, is the main pest in leek production, generally occurs in 4 generations a year, which occur in early May, mid-June, early August and late September. Adults lay eggs in the soil crevices or clods around the leeks, after the larvae hatch and dissipate, the bulbs and tender stems that gather in the underground part of the leeks are harmful, causing the young stems to rot, making the leek leaves yellow, until rotting and dying, and in severe cases, the whole leek plant dies. In order to prevent and control leek maggots, some vegetable farmers use highly toxic pesticides to irrigate roots, use soil to sprinkle roots and other methods to treat the soil, although it can receive a certain control effect, but it will cause serious pollution to leeks and cause significant damage to the health of consumers.

In order to adapt to the new situation after joining the WTO and ensure the safety and hygiene of consumers, the following introduces some pollution-free prevention and control technologies for leeks and maggots.

1. Mulching after harvest to prevent adult insects: After the leeks are just harvested, a large number of adults are attracted to lay eggs because of the strong leek flavor floating over the leek furrows. Therefore, after the leek is harvested, it is necessary to immediately cover the leek furrow with plastic film for 3 5 days, and then remove the film after the leek wound heals and the smell disappears.

2. Drug spraying to kill adult insects: In the adult fewing period (mid-to-late April, early to mid-June, mid-to-late July and early to mid-September), spray the wine furrow surface with a low-toxicity pyrethroid pesticide 25oo-3ooo or 75 phosphine looo times, which can directly kill the adults, and the spraying effect is the best at 9 lo in the morning.

3. Irrigation with medicinal fertilizer to kill larvae: when larval damage occurs in the field, combined with watering, ammonium bicarbonate L5 2O kg per mu can be effectively killed by watering. In addition, l kg of copper sulfate per mu and 2oo kg of water are used to irrigate the roots of leeks, which can also receive good results.

1. Agricultural control methods: winter irrigation or spring irrigation can eliminate some larvae, and ammonia (8-10 kg mu) can be used. 2. Physical control methods for adult insects:

Make a solution of sugar, vinegar, wine, water, and trichlorfon in proportion, put it in a pot, and put 2-3 pots per mu. 3. Biological control method of leek maggot: apply leek maggot parasitic insect pathogenic nematode control.

First, the best way to control root maggots from leeks

1. Agricultural prevention and control methods.

1) You can use pesticides to irrigate vegetable fields in winter or spring, which can eliminate some larvae, and the pesticides can choose ammonia (8-10 kg mu).

2) You can dry the soil and dry the roots for 5-6 days, sprinkle 50% malathion powder or dimethoate powder (2 kg mu) or use emulsion to spray fine soil to make poisonous soil sprinkling.

2. Physical control methods for adult insects:

1) Sweet and sour can be used to attract adult worms.

2) How to use: Make a solution of sugar, vinegar, wine, water, and trichlorfon in proportion, put it in a pot, and put 2-3 pots per mu, so that it can trap and kill adults.

3. Biological control method of leek maggot: leek maggot parasitic insect pathogenic nematode can be used for control.

4. Chemical control.

1) In the peak period of adult emergence, you can use 10% chrysanthemum emulsifiable concentrate 3000 times, or deltamethrin 3000 times, or 20% fenvalerate 3000 times, or 50% phoxanthion emulsifiable concentrate 1000 times for spraying, spraying around 9-10 o'clock in the morning.

2) When the leaf tip is found to be yellowish and soft in the field and gradually lodging to the ground, it can be used to use 2000 times of 0% chlormona EC, or 5000 times of dichloride EC, or 2000-3000 times of 50% phoxanthion EC and other agents for root irrigation control.

2. Harmful symptoms of leek root maggots

1. Leek maggots are also called ground maggots and root maggots, and the maggots that harm leeks are mainly the larvae of the diptera late-eyed mushroom mosquito. Its larvae generally gather in the young shoots and bulbs in the underground part of the leek to eat, and in spring and autumn will eat the white stems in the soil, causing the rhizome to rot, and the leek leaves will begin to yellow and wilt and droop after being damaged until they are yellow and die. In summer, when the temperature is high, the larvae will move downward, mainly harming the bulbs, causing the entire bulb to rot, and in severe cases, large swaths of leeks will die.

2. Adult maggots are small flies with a body length of about millimeters and a gray to grayish-yellow body color. The larvae are maggot-shaped, milky white, the body length of the mature larvae is 9-10 mm, and the adult worms are small mosquitoes, about 3-5 mm long, and the body color is black-brown.

3. Adults prefer to be active in the damp and low-light environmental conditions, and their flight time is generally in the morning, afternoon and evening, and they mainly inhabit the soil crevices in the field. Adults have strong tropism to humus, yellow and sweet and sour taste, and females generally lay eggs in soil crevices, at the base of plants and in the crevices of leek leaf sheaths after mating.

The leeks that are harmful to leeks are mainly the larvae of the family Diptera, which gather underground to eat young shoots, bulbs, and false stems. Leek maggots can cause damage throughout the year. Spring, summer and autumn are harmful in open fields, and winter and spring are harmful in protected areas.

The temperature is suitable in spring and autumn, and the false stems and bulbs are mainly eaten in the shallow soil layer close to the surface. The leaves of the affected plant are yellow and wilted and drooping, which can be pulled out with a light lifting by hand, and a large number of larvae or pupae around the dead plant can be seen when the topsoil is peeled off. In summer, the larvae move downward, mainly harming rhizomes and roots.

Suitable soil moisture is conducive to the reproduction and survival of leek maggots. When the soil is dry, it will concentrate on the roots of leeks, and the damage will be significantly aggravated.

The larvae of leek maggots are thread-shaped, 6.9 mm long, with a black head, milky white carcass, smooth surface, pointed anterior end, slightly flat posterior. The adult is a small mosquito that is not good at flying and is afraid of bright light. They often gather in groups and lay eggs in place soon after mating, causing patches in the field, which is seriously harmful.

The eggs are mostly laid 3 4 cm below the ground of leek bushes, eating pseudostems and bulbs, and the larvae prefer to live in moist and juicy tissues. Generally, it is seriously harmful in wetlands and loam.

The control of leek maggots in greenhouses, greenhouses and other protected areas is generally based on irrigating roots to kill larvae. In winter, due to the increase in soil temperature, the larvae wake up, and the leeks that return to the roots are first picked up to remove the dry leaves, clear the ground, and the soil around the leek bushes is 3 4 cm deep after the head cutter of continuous cultivation in autumn and winter, and then irrigation. Commonly used agents are 50% phoxanthion 500 600 times solution or 90% crystalline trichlorfon 600 times solution.

Each hole planted in the hole needs 250 grams of liquid medicine, and the ridge planting is watered along the ridge after the ditch is opened next to the plant. Seal the ditch (acupoint) immediately after irrigation to give full play to the effect of the medicine.

In the production of protected areas, it is generally a combination of ditching irrigation and fertilization, after ditching (hole) every 667 meters 2 according to 300 kg of cake fertilizer or chicken manure plus 30 kg of urea, sprinkled in the ditch (hole), and then filled with medicine to seal the ditch (hole). This kills the eggs in the fertilizer.

4 5 days after sealing the ditch (hole) and then pick it up to check the larval death, if it is found that the ** is not complete, you can fill it again or choose another agent or increase the concentration. In short, the principle of thoroughness is the case. If no surviving larvae are found through inspection, they can be irrigated with water, hoeed and loosened after the ground is slightly dried, and the leeks will enter normal growth.

I'm going to answer the question of how long chlorpyrifos remains, first of all, chlorpyrifos is an organophosphate insecticide, which is effective for about a week when sprayed on the foliar surface, and is used in the soil, combined with fine soil, and has an expiration date of about three weeks.

In addition to chemical control of pesticides, agricultural, physical and biological control methods can also be used.

1. Agricultural prevention and control methods.

When the film is just beginning to grow in early spring or close to covering in autumn, choose warm weather, peel off the top soil of the leek pier, expose the "leek beard", and dry it for 5 7 days, which can kill part of the leek maggots.

2. Physical control methods for adult insects:

Using sweet and sour to trap adult insects, method: sugar, vinegar, wine, water, trichlorfon according to the ratio of 3:3:1:10: to make a solution, put it in a pot, put 2 3 pots per mu, can trap and kill adults.

Ordinary fluorescent lamps can also be set up in the greenhouse, and a basin of water can be placed under the lamp to trap and kill leek maggot adults.

3. Biological control method of leek maggot: the application of leek maggot parasitic insect pathogenic nematode control, the test proves that the effect of small curly moth nematode and heteromicrorod nematode control leek maggot can reach about 70.

You can use Zhongke Fengyun's products to treat leek maggots, and I have done a demonstration field, and none of the leeks can run, thank you.