Now that agricultural planting nematodes are rampant, what are the good control methods and drugs?

There are many nematode species in the soil, and there are as many as seven species of nematodes infected in the planting process of many crops, such as bud nematodes, stem nematodes, root rot nematodes, and root-knot nematodes. Nematode damage in crop production has seriously affected yield and quality. From nematodes ** and control methods to this question.

One, nematodes**

Nematodes are a member of the soil microbial flora, and the changes in the soil environment have led to a sharp increase in the number of different species of nematodes, occupying a dominant position in the soil microbial flora.

Soil acidification, reduction of organic matter, reduction of the number of beneficial microorganisms, and application of unrotted farm manure provide opportunities for soil nematodes to reproduce and aggravate the damage of nematodes.

Soil nematodes in protected areas are mainly found in different plots of soil nematodes to carry and spread artificially, soil fertilizer application, soil acid-base imbalance, soil continuous cropping and heavy cropping obstacles, chemical nematicide resistance, plant disease residues, and incomplete soil disinfection. <>

Second, nematode prevention:

1. Soil disinfection treatment to reduce the harm of nematodes.

Chemical pesticides nematicides include avermectin, thiazolphos, fluopyramide, etc.; Chemical fumigants nematicides include Mianlong, chloropicrin, Wei Baimu, etc.; Biological nematicide preparations include Penicillium lavender, Verticillium pachyspora, some Bacillus thuringiensis, etc.; Physical methods of nematicides include flame disinfection, steam disinfection, solar high-temperature disinfection, etc.

2. Farming and irrigation methods.

When cultivating soil with serious nematode damage, agricultural operations should be carried out separately from the soil without nematode infection to avoid cross-infection. Irrigation water for soils with severe nematodes to avoid contamination of healthy soil irrigation water. The selection of high-quality substrate for seedling breeding or crop cultivation can significantly reduce the damage of nematodes.

Using coir substrate or soilless cultivation techniques, nematodes are very harmless. <

3. Nematode management

Control methods of root-knot nematodes:

Method. 1. Use the contact nematicide benzenophosphine: 3000 5000 grams of 10% granules per mu are applied to the soil with crop sowing, or applied to the soil near the rhizosphere during the crop growth period.

Method. 2. Use the contact type light insecticide to kill the line phosphorus: apply 20% granules per mu with kilograms of water or spray it in the soil, (note that the line of phosphorus can not be in direct contact with crop seeds, and it is easy to produce pesticide damage).

Method. 3. Use fumigation of nematicide Wei Baimu: 3 kg of 35% aqueous solution per mu, 300 kg of water, half a month before sowing, open a ditch to pour the potion into it, cover the soil, and sow it after 15 days.

Method. Fourth, with fumigation nematicide Mianlong: 11 kg per mu or furrow, immediately after the application of the soil covering, can effectively kill nematodes.

Summary: Root-knot nematodes mainly damage the roots of various vegetables, after the root is damaged, the plant is underdeveloped, the fibrous roots and lateral roots increase, and the formation of spherical or conical nodules of different sizes in the roots, the nodules are white at first, the texture is soft, and then turn brown to brown. The aboveground growth of the damaged plant was dwarf, slow, and the leaf color was abnormal, resulting in few fruits, low yield, and even the whole plant wilted and died.

The first is the drug**, such as the use of dichlorvos, and secondly, clean up some debris in the field, and in the last three days, go to the field to check the situation.

The inundation of planting nematodes will generally take two measures of pesticide control and biological control, pesticide control will take the form of aircraft spraying pesticides, manual spraying of pesticides, etc., and biological control will generally take the introduction of natural enemies to protect crops.

Don't choose the kind of seedlings with larvae, improve the microbial structure in the soil, and you can also use avermectin, thiazolphosphine and other drugs to kill insects, which can prevent pests from invading crops.

The first best way to prevent and control is to take a special agent, spray twice a day, so that the plant nematodes can be well eliminated, and the second way is to carry out the sun's drying, so that the plant nematodes slowly disappear.

Nematodes are subterranean worms that are common in potted flowers. It is a white thread-like mollusk insect that is not easy to see with the naked eye, and is very harmful to the callus of the young roots, young stems, bulbs, bulbs and cuttings of potted flowers. When the damage is severe, the aboveground part of the potted flower withers and dies.

The following methods can be taken to prevent and control:

When nematodes are found, if possible, they should be repotted, all the old soil should be removed, or the roots of the flowers and trees should be washed before repotting and planting. Nematodes can be fumigated with solutions such as methyl bromide and formaldehyde. After the potted flowers are watered thoroughly, cover the potting soil with a layer of 2 cm thick fine sand mixed with pesticides, the nematodes because the potting soil has been watered thoroughly, the air in the soil is insufficient, and soon burrow into the sand from the wet potting soil to breathe, and then remove the sand.

Do this 2 3 times can**.

Plant a few calendula plants next to the crop, the roots of the calendula release chemicals that kill nematodes without harming the crop. Specifically in the sixth chapter of the book Silent Spring can be seen.

(1) Strict seed selection; Select healthy and resistant tubers (2) to implement crop rotation for more than 2 years, and it is best to implement water-upland rotation crops to avoid rhizomes.

3) Immediately after harvesting, remove the diseased and remnants, and bury them deeply or burn them in a concentrated manner. Clean farm tools before and after entering the field to prevent spread with soil.

4) Apply 150-500kg of dry chicken manure per mu before planting, which has a high control effect.

5) before sowing ditch application of soil modification or 20 dibromochlorohydrin granules; It can also be used to modify the soil wireless 1 kg mu to irrigate the roots, 30 kg of special emulsion in addition to the line.

Root-knot nematodes mainly damage the root system of crops, and a lot of nodules grow on the root system when infected. When the damage is more serious, the plants on the ground will slowly become very slow to develop, and the leaves will become dull and yellow, which will directly affect the yield of the later fruits. There are also some roots that will rot, causing the plant to die, which is really very harmful.

The prevention and control has high temperature prevention and control, and the high temperature stuffy shed will kill all the bacteria and harmful bacteria in the soil.

Chemical control of avermectin has a fast effect, but there are pesticide residues, and it is easy to produce resistance, and the effect is becoming less and less obvious.

Although the effect of biological control and control line is not as fast as chemical control, there is no pesticide residue.

Prevention and control methods.

1. Agricultural measures.

Use insect-free soil for seedlings to raise. When transplanting, remove the insect-bearing seedlings or remove the "root nodules". Remove the carcass of the insect, reduce the density of the insect population, and burn the roots of the insect after drying.

Turn the soil deeply. Turning the topsoil below 25 cm can reduce the occurrence of insect infestations. Crop rotation for insect control.

In fields where nematodes occur a lot, changing to insect resistant (tolerant) crops such as grasses, onions, garlic, leeks, peppers, cabbage, cauliflower, etc., or planting aquatic vegetables can reduce the occurrence of nematodes. High (low) temperature inhibition insects. Take advantage of the high temperature in summer and the leisure season, ridge irrigation and mulching, and seal the shed for two weeks.

The occurrence of nematodes can be inhibited by using low-temperature freeze in winter.

2. Pharmaceutical prevention and control.

Soil treatment before planting: 10% gram phosphorus, 3% milel, 5% Yishubao and other granules can be selected, and 3 5 kg per mu can be evenly sprinkled and turned into the soil. You can also use one of the above-mentioned agents, 2 4 kg per mu in the ditch application on both sides of the planting line, or with the planting hole application, the amount of medicine per mu is 1 2 kg, and the soil mix after application prevents the root system from being in direct contact with the agent.

<> crops suffering from root-knot nematode disease, drugs such as gram phosphorus can generally be used for prevention and control. Root-knot nematodes mainly harm the roots of various vegetables, which are manifested as more lateral roots and fibrous roots than in normal periods, take plum and form spherical or conical white root nodules of different sizes on the fibrous roots of young roots, some are in the shape of rosary, and crops will grow slowly, low yield, abnormal leaf color and other phenomena after being infected, and even late in severe cases will cause early death of crops.

It can be controlled with pesticides, or to understand the symptoms of nematodes, or to carry out comprehensive **, or to strengthen management to prevent this symptom in advance. Nematodes are more difficult, and will affect crop yields, and there will be a lot of diseases, and will spread in a large area, the impact on crops is very large.

You can spray some medicines, you can also sprinkle some pesticides, you can also sprinkle some insect repellents, you can also sprinkle some insecticides. My understanding is that when this pest occurs, it should be carried out immediately, so as to prevent crops from being harmed and ensure the yield of crops.

At this time, pesticides should be replaced in time, and then insecticides should be used in time, and at the same time, the temperature of planting should be paid attention to, and watering should be done in time, fertilization should be applied in time, and weeding should be done in time.

To choose excellent varieties in progress, as long as the pesticide is sprayed in advance, the soil should also be sun-dried at high temperatures, the soil should be turned over regularly, and the rain should be prevented, and the drainage system should be improved.

Soil disinfection before planting is the most important, generally use quicklime! About 30 catties per mu!

1. It is necessary to stuff the greenhouse and use the natural high temperature to kill the nematodes in the shed. When stuffy shed, sprinkle a layer of 4-5 cm thick crushed straw on the ground, evenly sprinkle 25 kg of quicklime, a bag of biological fertilizer, turn it evenly, water it again, and buckle the shed to heat up. Nematodes over 15 cm can kill about 90%.

2. When planting vegetables, if the growth period is long, the rhizosphere soil can be treated with phosphine. Low-toxicity pesticides such as avermectin and chlorpyrifos are used for short growth periods. During the growth period, the roots are irrigated 1-2 times.

nematode occurrence can be controlled.

You can find this concentration of nematode drugs on the Internet: root-knot nematodes.

It's full of good information.

You can use a bio-fertilizer, one per plant, which works well and leaves no residue.

At present, there are a variety of nematicides in China's pesticide market, because most of them are highly toxic, the state only allows a few nematicides to be used in vegetable fields. Among them, nematicides include root-knot scattered slow-applied granules, avermectin emulsifiable concentrate, 10% thiazolphosphine granules, 35% Weibaimu water agent, 98% must-kill microparticles, etc. In order to ensure the food safety of consumers and effectively prevent and control vegetable nematode diseases, vegetable farmers first strictly select the above-mentioned types of high-efficiency and pollution-free series of nematicides.

Method of application. a) Nematicides are generally used for soil treatment before vegetable planting. Non-fumigant agents are commonly used in two ways: comprehensive treatment and centralized treatment, in which emulsifiable concentrate is sprayed or watered by adding water, and granules are sprinkled with fine soil or fine sand. The comprehensive treatment method, that is, the surface soil of the whole vegetable field is evenly applied, that is, the surface application, and then the control effect is good after rotary tillage of 15-20cm, but the disadvantage is that the dosage is large.

Centralized treatment method, that is, the sowing row or transplanting row adopts the drug method of furrow application and hole application, because the agent is concentrated in the nematode and root system, the activity range of the root-knot nematode is small, so the effect of controlling the root-knot nematode of local vegetables is ideal, and the drug is more economical, and the disadvantage is that the soil that does not kill the nematode between the rows can be cultivated in the roots, resulting in a shorter effective period.

2) After the nematicide is applied on the surface, the agent can be evenly distributed in the tillage layer through tillage, furrow application or hole.

The application of the pesticide is limited to a certain range at the bottom of the ditch or the bottom of the hole, and it is difficult to ensure that the larger tillage layer is also uniformly medicated, so.

The control effect of surface application can be higher than that of furrow application or hole application. Regardless of the method of application, it must be spun immediately after application.

Plough or cover the soil to reduce the exposure time of the agent, so as not to reduce the efficacy of the drug.

3) Fumigation agents are used to treat the soil nationwide with the help of diffusion and permeability. The fumigation is different, the specific requirements are different, and it should be operated strictly. After the application of fumigant, it must be immediately spun (surface application of granules) or cover soil (furrow application), and then cover the film (Mianlong needs to be watered first and then covered with film), which lasts for 15-20 days and then the film is removed, and vegetables can be planted only after full ventilation.

Note] It is forbidden to use highly toxic and high-residue pesticides in vegetable production. Including methamidophos, hydroamidophosate, dimethoate, dicophosphine, carbofuran (carbofuran) synergistic methamidophos, methyl parathion (methyl 1605) methylisosulfonate, quithion, monocrotophos, phosphine. Difenphosphine (strong wind and thunder), rapid culling, methocarb (Wanling), aldicarb, putterdam, insecticide, ferridine, insecticide, ulcer net and other highly toxic and high-residue pesticides.

It also requires that commercial vegetable plots implement rotation of vegetables with other crops, and must not use highly toxic and high-residue pesticides in other crop production seasons.

The simplest and most effective methods of nematode control are: crop rotation, soil improvement, sun exposure, flooding, grafting, etc.

1. Crop rotation: Crop rotation of cruciferous and Asteraceae and other root-knot nematode-resistant crops can secrete secondary metabolites that inhibit root-knot nematodes in the soil. Trap crops are crops with short growth periods, low economic value, and susceptibility to root-knot nematodes, which can be used to "trap" root-knot nematodes and harvest them before the females mature and lay eggs.

2. Soil improvement

The guest soil method is used to remove the infected soil and move it into clean soil, which is simple, effective and relatively low-cost. Add organic fertilizer to reduce the density of root-knot nematodes in the soil, improve soil texture, enhance water retention capacity and organic matter content.

3. Sunlight exposure

The solar exposure method is to cover the soil with a transparent polyethylene film in an area with sufficient sunlight, and increase the temperature of the upper soil by intense sunlight. This method works better when combined with nitrogen-rich composting or lime nitrogen treatment.

4. Flooding method:

The flooding method is to use the method of flood irrigation to saturate the soil water content, and after adding wheat bran or ethanol to cover the film, the effect will be significantly improved.

5. Grafting: It is an economical and effective method to use rootstocks selected from commercial high-root-knot resistance nematode crops and wild high-root-knot resistance nematode plants to graft with root-knot nematode-susceptible crops such as tomatoes, cucumbers, and watermelons.