Common disinfection methods for substrates

Before preparation, the matrix should be processed to grind off the sharp surface so as not to damage the root. And then sterilized. The common methods of disinfection are: steam disinfection, drug disinfection, sun exposure and freezing.

1. Steam disinfection any device can be used, as long as let steam through the substrate for 1 hour, can kill weed seeds, insect eggs, germs, bacteria, viruses and so on. The substrate should be dried or dried before disinfection to make the steam more effective and effective.

2. Drug disinfection, fumigation or spraying can be used. Fumigation can be fumigated with methane bromide (CH3Br), disinfected in a closed fumigator for 24 hours, can completely remove a variety of bacteria and insect pests, is the most thorough way of disinfection. However, because the fumigation machine is more expensive, there is no such equipment in the orchid field, so it is commonly used to spray formalin (40% formaldehyde) plus 50 times water spraying, with 400mL per centimeter, sealed for 2 weeks after spraying, and placed for 10 to 20 days after opening.

3. Exposure will spread the matrix on the cement floor, let the scorching sun directly shine for 3-7 days, generally can kill fungal spores and eggs.

4. Weed seeds, fungal spores and eggs can be killed when frozen in a low temperature refrigerator and frozen at minus 20 ℃ for 24 hours for 48 hours.

Because of the high cost of large-scale disinfection, the tiles, broken bricks, gravel, pottery stone and charcoal in the matrix can be picked out before disinfection and washed with water, while the organic matter, especially the powdery matrix of concealed germ spores, worm eggs and grass seeds, can be disinfected effectively. But water moss is a living plant, which can only be cleaned but not sterilized. (Chen Xinqi, Ji Zhanhe)