Grain Spawn Inoculation

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Grain Spawn Inoculation

Mushroom Spawn: Definition:
The mycelium, or primary filamentous growth, of the mushroom; also cakes of earth and compost/manure containing this growth, which are used for propagation of the mushroom.

The Life Cycle of a Cultivated Mushroom:

First, one must grow the spawn of the mycelium. Grain such as rye is often used for this task. While the spawn is starting to grow, composting of the manure takes place. Components such as manure, straw, chicken droppings, and/or turkey droppings can all be added to the mixture (but not acidic pine needles). Once this compost reaches the proper temperature, mushrooms growers will add the spawn to the nutrient-rich compost.

In turn, the mycelium will run all throughout the compost eagerly digesting the organic material. In order to coerce the fungus into creating mushrooms, a low-nutrient casing is placed on top of the compost. Thinking it is about to run out of food, the fungus will produce fruiting bodies (mushrooms) to disperse spores. When just the right time has come, harvesters will come along and cut the mushrooms away from the mycelium.

What you need:

Jars of prepared substrate
Spore syringe(s)
Bottle of rubbing alcohol
Paper towel
Pen marker
A very hot flame! (alcohol lamp, de-natured alcohol and a shotglass, a torch lighter, etc...)

You will need to create a hot enough flame to sterilize the needle tip between inoculations or jars. For this application, an alcohol lamp is considered ideal, but a torch lighter is also usable. However, if you don't have one handy then you can compromise by using a shotglass, glass lid belonging to a cooking pot, or similar heat-resistant glass object.

The procedure for inoculating a jar is as follows:

1) Shake the syringe very well to agitate the spore solution within the cylinder. Check to make sure that any air bubbles are worked out of the cylinder.

2) Flame or sterilize the tip of the needle.

3) Remove the tape covering the hole in the lid and carefully insert the tip of the needle into the hole. Steps 2 and 3 are done at the same time so the needle is still sterile when it reaches the inside of the jar.

4) Aiming for the sides of the glass (directly above the grain), squeeze the spore solution into the jar while rotating the syringe needle around the inner jar in a circular fashion making sure to spread the solution out around the whole circumference of the jar. You will need to pay close attention not to go over 2-3 cc's per jar. You can position the syringe in your hand so that you are able to read the markings better. It may help to draw markings on the cylinder with a pen to help serve as a guide. Eventually, you should be able to just go by "feel" and come suprisingly close to the mark every time

5) pull the syringe out of the jar and recover with the tape as rapidly as possible.

6) wipe the syringe clean with an alcohol-saturated towel and set aside.

7) Mark the jar with a pen to indicate the necessary information for your reference:

Strain/Variety: GT
How many in the batch: 1 of 5
date of inoculation: 12/02
transfer or syringe: SS (spore syringe)

Now, just repeat the process for each jar until you are done. That's it! The jars are now ready for the Incubation Chamber

Conditions for Successful Mushroom Cultivation

Phase/Cycle Substrate Temperature Relative Humidity Fresh Air Exchanges Light Duration
Spawn Run 84-86 ' F 90% + 0 per Hour Darkness/ Incubation 10-14 days
Primordia Formation 74-78 ' F 95-100% 1-3 per Hour 12-16 Hrs 6-10 days
Cropping 74-78 ' F 85-92%(CTC*) 92-96% (uncased) 1-3 per Hour 12-16 Hrs Every 5-8 days

Selecting a Good Spore Match
Some of those seven jars will show signs of very slow mycelia growth while others, showing signs of early mycelia growth, will appear to colonize at a much faster rate. It is also very possible that some jars will not show any signs of growth whatsoever.

The jars that show signs of early growth and appear to colonize at a much faster rate will be the ones to produce the best potential yields and fruit bodies (mushrooms).
The jars that show the slower signs of mycelia growth, and appear to be weaker in their mycelia structure, will produce less potential yields with fruit bodies that are likely to be less than ideal.

In fact, there is a chance that these jars may not even make it to the fruiting stage where mushrooms are produced.

For this reason, the jars that show the signs of lesser performance should be removed from the batch, leaving only the best jars to work with in order to obtain the best possible performing strain. Selecting the best jar to work from will ensure that the end result will be worth the cultivator’s effort by producing the best possible crops.

Spawn Transfer
Once you have obtained a master spawn jar, this can now be transferred to fresh new jars for further generation of mushroom substrate that can then be used as a final fruiting medium.

By doing this, the total amount of substrate mass can be built up to the desired amount by using the initial master jar to spawn other prepared jars.

Once the transfer is made, the newly prepared jars of fresh substrate will colonize quite rapidly, in most cases, the new jars of prepared substrate will reach full colonization within a week. After this point, they can all be combined together to provide a sufficient substrate mass and mycelia network that will produce better than usual yields in much less time than usual.

This process is best carried out when using rye grain as the prepared substrate since it offers many advantages that make this overall method easier to work with. The ability to transfer grain is more ideal than a concentrated substrate like brown rice flour, in that it is easily shaken and easily poured or transferred into new jars. The ability to shake a grain jar also helps to speed up the colonization time since the initial growths of mycelium that first appear can be shaken and spread around for better distribution throughout the substrate.

A guide for preparing jars of grain substrate, as well as the items needed to carry out the procedure, is listed below. It is a very simple and uncomplicated procedure that is worth considering, even for the first-timer.

Grain to Grain Transfer:
How to create multiple jars from a single jar of selected grain spawn that will all share identical and compatible strain characteristics.

Step #1
After the jars have fully colonized and a good match or master jar is chosen, you will want to shake the jar very well to break up the colonized grain into individual kernels that can be poured out into the newly prepared jars of fresh substrate.

Step #2
Heat oven up to 400’ and then open door and pull out heated rack to work over. With both the master and a freshly prepared jar of grain handy, unscrew the lids and pour a small amount of colonized grain into the fresh jar as quickly as possible and as closely as possible to the rack and cover with the lids. Repeat this until all of the freshly prepared jars have been spawned by the master jar of colonized spawn.

That’s it!!
Place the jars back into incubation and you should see signs of growth by the next day and full colonization should be reached within a week. All of the jars will perform identically and should be ready for use at the same time.

Large Grain Cake Preparation
To prepare a single large cake made of grain, you will need to first follow the procedure above for creating mass jars of the same grain spawn. Once you have created the jars of substrate needed that can be combined together to work as a single compatible strain, then you are ready to prepare a single large grain cake.

A container such as a 1-3 Qt bowl works best for this procedure. It can be made of plastic, foil, glass, or a similar type of material.

Items needed:
1 large bowl (1-3 Qt.) plastic, foil, glass, etc.
12" x 12" of aluminum foil, saran wrap or similar
Bleach or rubbing alcohol

Step by Step Procedure
Step #1

Once you have the bowl selected, you will need to clean it with either a mild bleach solution (10%) or a paper towel soaked with rubbing alcohol. Now, clean the area that you will be working in, such as the kitchen counter top with Lysol or bleach, etc.

Step #2
Shake jars of colonized grain into individual kernels.

Step #3
Clean hands thoroughly with anti-bacterial soap and saturated alcohol towel.

Step #4
Open jar of grain and pour all of it into the clean bowl. Repeat this for each jar until the bowl is filled with grain.

Step #5
Using your clean hands, compress the grain into the bowl so that it compacts in the bowl. Add more grain if needed until bowl is packed and filled with grain.

Step #6
Cover with foil and place in incubation. Grain cake should be ready to “birth” after the 3rd day or so. Usually, by the 5th day the cake is ready to move into the pod. That’s it!

Shroom Glossary