Analysis on the causes of pollution in Ganoderma lucidum seed production

1. Damage and pollution

(1) the broken container is sub-packed, sterilized and inoculated; in the process of transportation and cultivation, it is not handled lightly and causes mechanical damage.

(2) sudden heating, pressure rise or sudden cooling during gas damage and sterilization; exhaust speed is too fast, so that the bag gas is damaged.

two。 Cotton stopper contamination

(1) the mouth of the test tube contaminated by the cotton plug is stained with the culture medium or the mouth of the bottle (bag) is not clean or the medium is in contact with the cotton plug.

(2) improper stacking of cotton plugs when sterilized by moisture, excessive addition of water, unreasonable masonry of sterilized stoves or too high humidity of culture materials, and cotton plugs are contaminated by moisture absorption.

3. Inoculation pollution

(1) the environment is not clean, the inoculation room is too large and not sealed, the environment of the inoculation room is not clean and the disinfection is not strict.

(2) the disinfection is not strict, the inoculation box is not airtight, the disinfection is not thorough or the super clean table is not turned on in advance before inoculation, and the inoculation tools and operators' hands are not sterilized or not strictly disinfected.

(3) the poor aseptic consciousness is not done according to the aseptic operation standard, and the requirement is not strict.

4. No species to carry bacteria

The main results are as follows: (1) in the process of checking the mother species and original seed culture, the impurity is not checked regularly, and the miscellaneous bacteria are covered by hyphae and are not found.

(2) if the work is not strict enough to transfer the tube or expand the mother seed, the contaminated bacteria are misused without careful examination.

5. Mixing pollution

The main results are as follows: (1) when the material is mixed unevenly, the culture material is not fully mixed, the cottonseed shell is not fully pre-wet, and the entrainment is granular or insufficient, resulting in partial dryness and forming a sterilization dead corner.

(2) when the raw materials are mixed with bacteria, moldy and stale raw materials are used, resulting in a large number of miscellaneous bacteria in the raw materials themselves.

6. Sterilization pollution

The main results are as follows: (1) the time or humidity of atmospheric pressure sterilization is not enough; high pressure sterilization does not rule out false pressure or pressure gauge failure caused by cold air.

(2) when stacking the tightening pot, it is too tight, which affects the penetration of steam and produces a dead angle.

(3) the serious air leakage is due to the fact that the air leakage in the sterilizer can not reach the required temperature.

7. Culture pollution

(1) the relative humidity of the humid culture room is too high, more than 70%, which is beneficial to the growth of miscellaneous bacteria and the pollution caused by moisture absorption of cotton plugs.

(2) the cotton plug is too loose and the miscellaneous bacteria in the air take advantage of the deficiency.

(3) the dirty culture room of the site is not clean, the density of miscellaneous bacteria in the air is high, and the site is not often sterilized.

(4) pests and rodents are harmful to rats to bite cotton plugs or bacteria bags and bring in miscellaneous bacteria. Or breeding mites, grain thieves and other insect pests in the culture medium.