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The cultivation process is divided into two Parts. Each Part consists of "Units", and each Unit is broken down into steps.
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Part 2 : Unit 1 : Germinating Mushroom Spores in Agar
Your mushroom cultivation journey starts with mushroom sporesmushroom spores in one form or another. Spores are usually obtained in one of three ways – Spore PrintsA spore print is a powdery deposit of spores which were released from the gills of a mushroom. Spore prints are usually taken on Aluminium foil., Spore SyringesSyringes which hold mushroom spores suspended in sterile water. and Spore SwabsThese are sterile swabs which have been dabbed in mushroom spores and placed back in a sterile case.
Regardless of how these spores are obtained, they need to be germinated and allowed to grow into mycelium. The germination medium used in this course is nutrient agarAgar mixed with nutrients such as honey or light malt extract powder. The nutrients provide food for the mycelium., stored in sterile petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes.. You will prepare the agar and pour it into the petri dishes in our Still Air Box, in order to reduce the exposure to contaminants in the air. Once the agar has set, you will put the spores on top of the nutrient agar inside the sterile petri dish, and allow them to grow.
Germinating these spores in agar first (as opposed to germinating them directly in Liquid Culture) allows us to identify whether our spores were not contaminated. If they were not contaminated, we should have clean, white mycelium growing in the petri dish…sections of which we will use in the next step, to inoculate Liquid Culture.
The video markers above 👆🏼correspond to the the various Steps in this Unit. Click on them to skip to a Step.
Weigh out the agar and LMELME is an acronym for Light Malt Extract – used as a nutrient source in mushroom cultivation. powders and mix with 1 liter of non chlorinatedWater with no chlorine in it. This can be mineral water, distilled water, or boiled water which has cooled off. water. Pour the liquid nutrient agarAgar mixed with nutrients such as honey or light malt extract powder. The nutrients provide food for the mycelium. mix into the heat resistant flask. If you plan to use a magnetic stirrer, this is the time to place it in the flask. Loosely tighten the cap of the flask, and cover the cap and neck of the bottle with aluminium foil. Fill the PCAn acronym for Pressure Cooker. with 1.5 inches of water, insert the rack and then place the agar bottle on the rack so that it doesn’t touch the sides of the pot. Sterilize the liquid by Pressure cooking it for 30 minutes. Allow the PC to cool off to no less than 42 °C or 108 °F , otherwise the agar will solidify. If it does solidify, simply warm up the bottle in a hot water bath (inside a pot) until the agar liquifies again.
While waiting for the PCAn acronym for Pressure Cooker. to cool off, you can start cleaning up your workspace and SAB in anticipation for the Agar work ahead. Once the PC has cooled off to no less than 42 °C or 108 °F and is safe to open, remove the bottle of Agar, give it a gentle mix in the bottle (don’t shake). Sanitize and place the bottle in the SAB and wait for it to cool off some more. You want the Agar to be warm enough so that it stays liquid and doesn’t set in the bottle, but not too hot to hold for an extended period of time.
Next, sanitize the petri dish sleeve and place it inside the SAB so that the petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes. are standing the right way up. Proceed to sanitize and place everything else you will need (scalpel, paper towels, etc) in the SAB and spray the air in the SAB with alcohol a few times to bring down particulates.
Slice open the petri dish sleeve and stack the petri dishes in stacks of 5 or 10. With small movements, open each petri dish and pour in just enough liquid to cover the bottom of the dish. Try to keep the petri dish cover close to the base as you pour in the agar, so that the base is less exposed to falling contaminants in the air. Cover the dish quickly and proceed to open and pour the next petri dish. Complete all dishes in batches of 5 or 10, and allow them to cool off in the SAB for about 30 minutes. You can loosely cover the holes of the SAB with some paper towels, and keep the airflow low in the room as you wait for the agar in the petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes. to solidify.
While you wait for the poured agar to harden, you can cut parafilm strips which you will use to wrap and seal your petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes.. I usually cut 6-8 inches of single strip per dish. Once you are ready to start wrapping your petri dishes, grab a parafilm strip and separate it from the paper. If you’re having trouble separating them, pinch off the corner of the parafilm strip to help remove its paper cover. Wrap each dish so that the whole circumference of the dish is covered in wrap. You can stretch the wrap as you pull it around the dish. Practice this a few times to get a feel for the elasticity of the parafilm. Once you have completed wrapping all the dishes, mark the date on each dish and store in a place where they won’t be disturbed for a few days. If any contamination entered the dishes during the pouring process, it will hopefully reveal itself in the next few days.
While you wait for the poured agar to harden, you can cut parafilm strips which you will use to wrap and seal your petri dishes. I usually cut 6-8 inches of single strip per dish. Once you are ready to start wrapping your petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes., grab a parafilm strip and separate it from the paper. If you’re having trouble separating them, pinch off the corner of the parafilm strip to help remove its paper cover. Wrap each dish so that the whole circumference of the dish is covered in wrap. You can stretch the wrap as you pull it around the dish. Practice this a few times to get a feel for the elasticity of the parafilm. Once you have completed wrapping all the dishes, mark the date on each dish and store in a place where they won’t be disturbed for a few days. If any contamination entered the dishes during the pouring process, it will hopefully reveal itself in the next few days.
Clean and disinfect your workspace and SAB if needed. Disinfect all required items including spore prints or syringes, agar plates, sterile knife or scraper and paper towels, and put them into the SAB. Spray down the air in the SAB a few times to bring down particulates. Unwrap the parafilm from the nutrient agarAgar mixed with nutrients such as honey or light malt extract powder. The nutrients provide food for the mycelium. petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes. and give them a light sanitization by wiping them down with an alcohol soaked paper towel. Obviously, you don’t want any alcohol getting into the dishes, because alcohol kills the mycelium.
If you’re starting off with a spore syringe, this is your Step 2. Inside the SAB, spray down the air a few times to bring down particulates. Sanitize your hands and and give the spore syringe a good shake – you want to try to even them out in the spore syringe. Remove a new sterile needle from a wrapper and attached to the spore syringe. Open the agar plate and drip a drop or two around the center of the plate. Cover up the plate, and place the spore syringe in a clean ziplock bag.
Wrap the petri dish in parafilm and place it in incubation at around 22-27 °C or 70-80 °F. Check them every couple of days for growth of mycelium or contamination. If any dishes show signs of contamination, discard them, or carefully attempt to cut out the healthy parts inside a SAB, and place the healthy piece in a new agar dish.
Next Unit: Going from colonized agar to liquid culture. Learn how to choose clean, healthy mycelium from your colonizing petri dishesDishes made out of plastic or glass which allow for sterilization and storage of nutrient agar. Mycelium is then grown in these dishes. in order to inoculate Liquid Culture, create endless amounts of liquid mycelium.
2 Responses
Hi there, I just want to send this note to tell you how much I appreciate all your hard work and generosity in providing this tutorial. I am very grateful for people like you who dedicate their valuable time and resources to provide this type of education free of charge. Not to mention the cleanliness and details you put to your work and descriptions on teaching is amazing. As an broadcast engineer myself I understand how much time and effort it goes to getting this on paper and video as suppose you just doing it for your daily production.
Keep up the good work and hopefully one day I will be able to meet you in person to thank you. I been using your method to learn on how to grow as a beginner so that I can open my business in oregon next year and hopefully I will do it as half good as yours. 🙂
Cheers…
Tammie
Thank you so much for your kind words. It’s very gratifying, and definitely made my day. I wish you the best of luck on your journey – and don’t hesitate to reach out for assistance.