Mushroom Cloning: Advanced Guide for Mycological Cultivators

Mushroom cloning is an essential technique for mycologists, whether amateur or expert. It allows for faithful reproduction of the characteristics of a specific specimen and maximizes yields in cultivation. This detailed guide explains the benefits, methods, and practical steps to successfully clone your favorite mushrooms.

Introduction to Mushroom Cloning

Cloning, in mycological terms, involves taking a piece of tissue from an existing mushroom and cultivating it to create a genetically identical copy. This method is especially useful when you want to preserve the specific characteristics of an exceptional mushroom. Unlike cultivation from spores, cloning allows for consistent and reproducible results.

Why Clone Mushrooms?

1. Preservation of Unique Strains

By cloning mushrooms found in nature, it is possible to cultivate rare or uncommon strains. This contributes to the preservation of fungal biodiversity and can even lead to the discovery of new varieties. Passionate cultivators use this method to protect local, threatened, or medicinal species.

2. Reproduction of Specific Traits

Cloning allows reproducing mushrooms with particular characteristics, such as fast growth, large size, or enhanced medicinal properties. By doing so, it is possible to stabilize a lineage that will consistently offer exceptional qualities during harvests.

3. Time and Money Savings

By cloning a mushroom, you reduce your dependence on spores, which can be costly and sometimes have a low germination rate. Starting from a clone, it is easier to produce mycelium and start new cultures.

4. Preparation for Outdoor Cultivation

Some wild species can adapt to cultivated environments by first cloning them under controlled conditions, then gradually acclimating them outdoors. This allows reproducing mushrooms with strong resilience to varied environmental conditions.

Selection of the Mushroom to Clone

Choosing the mushroom to clone is crucial for the success of the operation. Here are the criteria to consider:

• Mushroom Health: Avoid mushrooms showing signs of disease or contamination, as these issues can persist in the cloned mycelium.
• Specimen Freshness: Favor a freshly picked mushroom to maximize the chances of success. Fresh tissues have more vitality and are less likely to harbor contaminants.
• Desirable Characteristics: Identify the traits you want to reproduce: size, growth rate, mycelium density, etc. Specimens with these qualities will be the best candidates for cloning.

Necessary Equipment

To clone mushrooms, you will need:

1. Agar Plates : A basic malt agar recipe works well to start. It is possible to use pre-poured plates or prepare them yourself. We particularly recommend our Sabouraud media with chloramphenicol. The addition of this antibiotic will limit bacterial growth, which is often problematic for beginners and professionals working with mushrooms collected from the wild.
2. Fresh Mushroom : The mushroom must be of the same species as the one you want to cultivate. We recommend cleaning it well with a brush, then rinsing it with water. If possible, immerse it for 30 seconds in oxygenated water; this will deactivate most potential contaminant spores with minimal impact on the mycelium.
3. Sterile Environment : A laminar flow hood, a still air box (glove boxes), or a Bunsen burner to limit contaminants. In your kitchen, you can work as close as possible to your gas stove.
4. Sterile Scalpel : Sterilize it with a flame before each use.
5. Sterilization Products : Use 70% isopropyl alcohol or a diluted bleach solution to clean equipment and work surfaces.
6. Adhesive Tape or Parafilm : To seal petri dishes and prevent contamination.

Cloning Methods

Traditional Method with Agar

1. Preparation of Petri Dishes
   Prepare your petri dishes according to our user guide, or order our pre-poured petri dishes. Clean the work surface, tools, and disinfect the mushroom to be cloned.

2. Tissue Sampling
   Tear the mushroom to access the sterile internal tissues. Take a small piece of flesh and place it on the agar. Use a sterilized scalpel by passing it through a flame beforehand to avoid introducing contaminants. The piece must be small; the larger it is, the more likely you are to bring contaminants. Cut a triangle: in 3 movements you can take a small piece of 2-3 mm².

3. Incubation and Monitoring
   Seal the boxes with adhesive tape and place them in a temperature-controlled environment (between 21 and 24 °C). Monitor mycelium growth and transfer healthy parts to new media for purification.

4. Isolation and Pure Culture
   If the mycelium grows without contamination, you have a pure culture ready to be transferred to a grain or sawdust substrate to continue growth.

Alternative Method: Cloning with Moist Cardboard

This technique is useful for outdoor situations or when laboratory equipment is not available.

1. Cardboard Preparation
   Soak the cardboard in boiling water to sterilize it, then let it cool.

2. Placement of Mushroom Tissue
   Place a piece of mushroom tissue between two layers of damp cardboard, then roll it up and place it in a plastic bag.

3. Growth and Transfer
   Let the mycelium develop inside the cardboard. Once it has fully colonized, you can transfer the mycelium to a more nutritious substrate.

Frequently Asked Questions about Mushroom Cloning

• How many times can a mushroom be cloned?
  Although cloning can be done over several generations, it is best to periodically use new genetic sources to avoid loss of vigor due to senescence.

• Can mushrooms bought in stores be cloned?
  Yes, as long as they are fresh. However, some species are easier to clone than others. Button mushrooms have particular nitrogen needs and are not the easiest to start with. We recommend starting with oyster mushrooms.

Maintenance and Preservation Techniques

It is recommended to store cultures at low temperature and regularly renew strains using spores or new strains to reintroduce genetic diversity.

Conclusion

Mushroom cloning is a fascinating and versatile technique, ideal for growers seeking consistent results while exploring mycology in greater depth. With proper sterile practices and good culture management, it is possible to master this technique and gain significant benefits for mushroom cultivation projects.