Methods for the Preservation of Edible Mushroom Spawn and Disease Prevention and Control

The degeneration of edible mushroom spawn is a common phenomenon. Adopting suitable preservation methods and minimizing the number of subculturing generations as much as possible is one of the effective measures to prevent spawn degeneration. The principle of spawn preservation is to reduce its metabolic activity. There are many preservation methods; two main ones are introduced here for the reference of mushroom growers throughout the city.

First, the slant low-temperature preservation method: This is the simplest preservation method, which involves placing vigorously growing, uncontaminated slant test tubes into a refrigerator and preserving them at a low temperature of 4—6°C. After that, they are subcultured onto fresh slant medium every 2—3 months, and after culturing, preservation continues (to replenish the nutrients and moisture for the mycelium and prevent mycelial aging).

Second, the liquid paraffin preservation method: In this method, sterilized liquid paraffin is injected under sterile conditions into the slant test tubes to be preserved, with the paraffin injected to a level 1 cm above the slant. Its purpose is to isolate the spawn from air and reduce its metabolic activity. Then a wooden stopper or rubber stopper is inserted, the opening is sealed with wax, and the tube is placed upright in a dry place indoors, where it can be preserved for more than one year. When

in use, simply use an inoculation needle to pick up a small amount of mycelium from the slant and transfer it onto fresh slant medium. Because the mycelium is contaminated with paraffin, it must be transferred once more to a test tube before it can grow well.