At present, it is at the late stage of planting and medium-term planting of vegetable crops in winter and spring in Beijing. In the prevention and control of pests and diseases during the nursery period to ensure that the seedlings do not carry pests and diseases, further efforts should be made to disinfect the planting sheds, in particular to disinfect the sheds, to prevent germs and small pests on the surfaces of the sheds. Damage seedlings. Having said that, we have to mention that the plant-sourced pesticide horseradish is used in the surface disinfection of the greenhouses of organic production parks. Today we will come to understand all aspects of horseradish. What is horseradish Horseradish is a class of secondary metabolites extracted from horseradish, mustard and other cruciferous plants and belongs to plant-derived pesticides. Its main components are isothiocyanate compounds, of which the content is allyl isothiocyanate, which has good biological activity against harmful microorganisms and pests and is a high-quality biological fumigant. In general, horseradish is the main ingredient of mustard that we usually eat, but the content of active ingredients is not the same. For mustard we eat, the effective content of horseradish in general is 0.2%, and the horseradishin water emulsion currently used for soil disinfection has an active ingredient content of 20%, which is 100 times that of mustard oil. It can be said that in the prevention of pests and diseases with horseradish, they are alive and “spicy†to death, “rushing†to death. What can horseradish do? Currently, horseradish is mainly used in the following areas: medical field, prevention of postpartum diseases, fumigation of storage pests, and soil disinfection. ◆The application of horseradish in medicine In the past 30 years, the anti-tumor activity of horseradish has been a research hotspot. The related compounds in horseradish have shown good preventive effects in the clinical research of cancer and malignant tumors, which laid the foundation for the development of clinical drugs. As early as 1989, there were studies abroad, and horseradish can inhibit the occurrence of gastric cancer and lung cancer induced by carcinogens such as benzopyrene and dimethylhydrazine. ◆ Application of horseradish in the fumigation of storage pests Horseradish is first used for fumigation treatment of stored pests. In the past 50 years, methyl bromide and phosphine have been the most widely used for the prevention and control of warehousing insect pests. Since October 1, 2015, the scope of registration and application of methyl bromide has been changed to soil fumigation. Other registrations except for soil fumigation have been implemented. It is revoked. At the same time, warehouse pests are widely resistant to phosphine. Plant-based fumigant horseradish is the plant material that is selected and purified from plants in this context. Application of horseradish in soil disinfection U.S. Jordan Agricultural Corporation has registered allyl isothiocyanate as a soil disinfectant under the trade name of Dazitol, which is extracted from red pepper and mustard. Its active ingredient is allyl isothiocyanate 3.7%, capsaicin and related substances 0.42. %. According to the company, Dazitol is used for soil treatment and can effectively kill or inhibit nematodes, pathogens, and weeds in the soil. The study found that under the same active ingredient, Dazitol has similar activity to Weibaimu in terms of bactericidal, nematicidal, and weed removal, and is a potential soil disinfectant. ◆The application of horseradish in domestic production Beijing Plant Protection Station found that 20% horseradish water emulsion had a significant killing effect on soil fungi and bacteria, had no significant effect on the killing of soil actinomycetes, and had a killing effect on soil fungi. 100%, the killing effect on Pythium, Aspergillus, Penicillium and other fungi in the soil is remarkable. After several years of trials and optimization, the station initially proposed a technical specification for the use of horseradishrin to disinfect the soil and disinfect the surface of the greenhouse. Horseradishine soil disinfection technology ◆ Prevention and Control Objectives The use of horseradishrin in soil disinfecting treatment will prevent various diseases such as wilt disease, verticillium wilt, epidemic disease, and root-knot nematode disease. ◆ Tools and materials 20% horseradish water emulsion, drip irrigation system, plastic film. ◆Operation method Pastoral cleanliness, clean up the crops inside the shed, and completely remove the sick and waste. According to different crops applied suitable organic fertilizer, deep plowing the soil 30-40 centimeters, before processing should ensure that no large clods. Do trickling, laying drip irrigation systems, drip tests, and checking drip irrigation tubes for clogging. 2-3 days before application, drip irrigation with drip irrigation equipment every day to soak the earthworms. Covering the plastic film, covering the whole or single ridge, the plastic film with more than 4 wires has the best effect and is compacted at four weeks. Try to make the plastic film close to the ground and check whether the plastic film is damaged and repair it in time. Before application, first rinse with water for 15-30 minutes to allow the water to expand near the drip point. With the blending agent, it is now ready to use, with a dose of 4-8 liters/acre. Disperse 20% horseradish water emulsion 5-10 times and use drip irrigation with Venturi system. Drip irrigation time is about 30-40 minutes (short sand time, long clay time; short root system time, deep root system time) Ensure uniform application. After the drug is dispensed, continue rinsing with water for 15-30 minutes. Close the air inlet of the booth, close the booth and increase the temperature of the booth. Application of fumigation after 3-5 days can be opened plastic film, in order to ensure the disinfection effect, can increase the fumigation time. After dismantling the plastic film, it should be diffused for more than 3 days to completely volatilize the gas and avoid phytotoxicity. After dredging, the drip-irrigation systems drip-inoculated anti-microbial microbial agents and microbial microbial fertilizers, which can not only improve the soil disinfection, but also promote the growth of crops. Horseradish surface disinfection technology ◆ Prevention and control facilities There are about 70% of airborne diseases and small pests on vegetables from inside the greenhouse. The surface disinfection of the greenhouse before nursery seedlings cultivation and before the production sheds are planted can effectively reduce or delay the occurrence of pests and diseases. Before the disinfection, we must remove the discarded plant residues and weeds in the shed and seal the shed film. If the shed film is damaged, repair it in time. ◆ tools and materials at room temperature smoke sprayer or sprayer, 20% horseradish water emulsion, protective equipment, plastic film, film. ◆Operation method Choose 20% horseradish water emulsion 1 liter/mu, spray evenly inside the shed using room temperature aerosol sprayer or sprayer. Or add 2 liters of horseradish water emulsion 1 liter/mu to the fertilizing tank and drip on the soil surface evenly with the drip irrigation system. Because horseradish is extremely irritating to the human body, professional protective equipment such as eye masks, masks, gloves, and protective clothing must be worn when applying the drug. Closed room for 3-5 hours after application. Gently planted in one day. The fertilization device is a pressure difference type or a Venturi type. Before the application, dilute the mixture with water and then pour the diluted solution into the fertilizing tank. After application, flush the pipes with water to prevent equipment corrosion. What potential does horseradish have to tap In addition to the above applications in the field of crop pest prevention and control, horseradish is also having great potential for application in the following areas: During the crop growing period, low-dose horseradish is treated in the greenhouse to prevent airborne diseases and small pests. According to the current preliminary results for small pests, 80% of horseradish biofumigants at low concentrations have strong smoke-killing effects against B. tabaci, aphids, thrips, and spider mites. Within a certain range, with the prolongation of the fumigation time, the effect of fumigation on the four kinds of small pests is continuously improved, and the fumigation effect is proportional to the fumigation time within a certain range. However, because young plants are very sensitive to the fumigant, if the fumigation concentration is not well controlled, phytotoxicity is likely to occur. During the growing season, horseradish is applied at low dose to prevent root-transmission diseases and pests. As the tolerance of different types of crops to horseradish is not the same, poor control of irrigation roots is also prone to phytotoxicity. In the previous trial, it was found that six root vegetables including pepper, lettuce, eggplant, tomato, Chinese cabbage, and kidney bean were treated with 500, 1000, 2000, and 3000 times the concentrations of horseradish. The results showed that only when the cowpea was treated with 500 times horseradish, there was a phytotoxicity such as stem base shriveling, and the crop had no effect at other concentrations. After the vegetables are harvested, they are treated with horseradish and extend the shelf life. Studies have shown that when the horseradish concentration is 200 ng/L, the growth of Penicillium, Aspergillus flavus, and Botrytis cinerea can be inhibited and the spores can be killed. At present, experiments are being conducted to optimize the concentration and time of postharvest treatment (sprinkling or instantaneous soaking) using horseradish per plant for different vegetable crops. Http:// Anesthesia Medical Co., Ltd. , https://www.honestymed.com