1. Select the appropriate culture medium according to the characteristics of bacteria; 2. Take out as soon as possible after culture and put it into the refrigerator for storage, pay attention to the storage temperature of different bacteria, such as fungi, Vibrio cholerae, etc. need to be stored at room temperature; 3. Record the results of the identification of the strains, including growth, colony characteristics, staining reaction, etc. when preserving the strains; 4. The strain is divided into two sets of storage, one set is used for the preservation of the transmission, and one set is used for the experiments. Regular seed transfer, every 3 generations of identification.