Detailed Guide to Making Mother Culture Media for Edible Mushrooms

1. 800 g corn, 20 g glucose, 20 g agar, 1.5 L rice washing water. First cook the corn kernels in dilute rice washing water until a small number of kernels burst, then scoop them out and filter. Take the filtrate and continue heating (if the filtrate is less than 1 L, add clean water to make up the volume), add the agar and glucose, stir until the agar is completely dissolved, then dispense into test tubes, and after sterilization take them out and slant them to set.

2. 200 g fresh oyster mushroom or mushroom stipes, 20 g glucose, 20 g agar, 1 L water. The preparation method is the same as for potato dextrose agar medium.

3. Bran 2/3, cornmeal 1/3, plus an appropriate amount of lime. Moisten the bran, cornmeal and lime with water to a water content of 65%, then put into test tubes and press into a slant. This method is convenient in material selection and simple to prepare, and after inoculation the mycelium grows vigorously.

4. Cottonseed hulls 80%, bran 19%, lime 1%, mix well with water and dispense into test tubes (can be pressed into a slant). This method has the following advantages: first, it can be prepared at the same time as stock cultures and spawn cultures, without the need to obtain additional raw materials; second, the mycelium grows well and is not prone to aging.

5. Firmiana tree sawdust 90%, cornmeal 9%, lime powder 1%, mix well with water and dispense into test tubes. The sawdust is about 3 mm square. This method is good for preserving cultures.

6. Put 3 g rice and 4 mL water in each test tube, place in an autoclave and arrange into a slant, and sterilize at a pressure of 1.2 kg/sq cm for 40 minutes. Or place in a household pressure cooker, cover with the pressure limiting valve when steam sprays from the opening, and maintain for 50 minutes. This method is simpler and more convenient than the previous one, and after inoculation the spawn germinates well, grows vigorously, and it is easy to check whether it is contaminated by foreign microorganisms.

7. Some rice grains or wheat grains, boiled thoroughly but cooked yet not mushy. Scoop out and drain, add 1% lime powder, mix well and put into test tubes. This medium is rich in nutrients, and after transfer to stock culture the spawn germinates well, grows quickly, and is not easily contaminated by foreign microorganisms.

Experiments show that when a certain variety is transferred and expanded in the same formula medium, the superior qualities of the culture tend to degenerate, thereby affecting yield and quality. Selecting different media for transfer culture can better maintain the superior characteristics of the culture, play a role in rejuvenation to a certain extent, and lay a good foundation for high quality and high yield of edible mushrooms.