What are the benefits of fumigation? How to choose smoke agent?

The fuming agent consists of raw materials, combustion improvers, oxidants, etc. After being ignited, smoke is generated, and particles are generated to form aerosol in the air, which spreads in the protected area and finally uniformly deposits on various parts and organs of plants. The smoke agent does not need any machinery, as long as it is placed and ignited. After the smoke agent burns, it usually takes only 3-5 minutes for the smoke to spread in the greenhouse. The pesticide has high dispersibility and small particles, can float and slowly settle for a long time, including the front and back of walls, roofs, soil surfaces and plant leaves, and even penetrates into soil gaps, with high efficacy. Smoking method does not use water, will not improve the relative humidity of the air in the protected area, is not limited by weather conditions, and can be used in rainy and snowy days.

The selection of smoke generating agent should be based on the following principles:

One is to choose according to the purpose of medication. The right medicine is the most basic principle in selecting pesticides, and we can't blindly choose or arbitrarily increase the variety of pesticides. For example, before vegetables are planted in greenhouses, chlorothalonil smoke agent, sulfur and dichlorvos smoke agent can be selected for greenhouse disinfection; When controlling gray mold and leaf mold, you can choose quick-kill smoke agent, wolf or Lide smoke bomb. Phytophthora blight and chlorothalonil aerosol can be used to control epidemic diseases and downy mildew; If a variety of diseases occur at the same time, compound smoke can be used for prevention and treatment; Pests such as aphids and whiteflies can be controlled by chlorpyrifos and dichlorvos.

The second is to choose according to the size of the greenhouse space. If the greenhouse space is large, smoke agents with high content of active ingredients (25% ~ 45%) or low content (10% ~ 15%) can be selected. If the greenhouse is short, smoke agents with low content of effective components should be selected; Smoke agent should not be used in the shed below 12 meters, otherwise it will easily cause phytotoxicity.

Third, choose products according to the quality of cigarettes. Try to buy well-known manufacturers and products with good reputation, and beware of fake and shoddy pesticides. Attention should also be paid to the shelf life and storage of the smoke agent to ensure the normal efficacy.