What are the most commonly used mechanical disinfection methods in the process of industrial seedling raising?

1 dry heat sterilization method, principle: high temperature degrades or denatures macromolecules such as protein and kills bacteria; The advantage is good sterilization effect, but the disadvantage is long dry heat sterilization time; Applicable objects: Incineration is suitable for inoculation tools, contaminated articles, experimental animal carcasses, etc. ② High pressure steam sterilization. Principle: Under pressure, the boiling point of water exceeds 100℃, which can provide water vapor higher than 100℃. The advantages are good sterilization effect, wide application range and simple operation, while the disadvantages are that the articles must withstand high temperature and high pressure. Objects: high temperature resistant materials, common culture medium, physiological saline, buffer solution, glass, ceramics, etc. ③ Sterilization by steps. Principle: Use normal pressure steam (100℃) to kill vegetative cells, so that heat-resistant sporophytes such as residual spores can germinate after night culture, and then kill them by heat treatment. Repeated treatment for three times can achieve aseptic state. The advantage is that it can keep the nutrition of the culture medium, but the disadvantage is that it is troublesome to operate and takes a long time; Objective: The culture medium containing heat-labile nutrients or ordinary culture medium without autoclaving treatment. ④ Radiation sterilization. Principle: microwave, ultraviolet, G-ray and X-ray sterilization. Gamma rays have a very strong penetrating power, which can disinfect the sealed and packaged articles. Has the advantages that a certain space can be sterilized, and articles which are not heat-resistant or easy to deteriorate and taste when heated can be sterilized. The disadvantage is that it is generally only suitable for surface sterilization. Object: Articles that are not heat-resistant or easy to deteriorate and taste when heated. Pay attention to safe operation and prepare for radiation protection. ⑤ Chemical disinfectant for sterilization. Principle Chemical disinfectants can oxidize or react with macromolecules such as protein. The advantages are convenient use and low price, while the disadvantages are that some disinfectants are harmful to human body or have residues. It has a wide range of objects and can disinfect the surface of objects, laboratories and so on. ⑥ Pasteurization. Principle: maintain a high temperature for a certain time to kill; The advantage is that the original flavor of sterilized articles can be maintained, and the disadvantage is that sterilization is not thorough; Applicable object: it is suitable for low-temperature disinfection of liquid flavor foods or seasonings such as milk, beer, fruit wine or soy sauce, which are not suitable for high-temperature sterilization.