ABC’S OF MYCOLOGY PART 6

Quiescent

Todays first term is quiescent. Quiescent mycelium represents a vital survival strategy in
the fungal kingdom, functioning as a state of temporary dormancy or metabolic
suspension. When environmental conditions become hostile, such as during periods of
extreme drought, freezing temperatures, competing organisms being present, or
nutrient scarcity, the vegetative fungal network (mycelium) ceases its expansive growth
to conserve energy. Rather than dying off, the cells enter a “standby mode,” slowing
their biological processes down to the bare minimum required to maintain life. This
adaptive pause allows the organism to withstand stresses that would otherwise be fatal,
preserving its genetic material until the environment becomes hospitable again.
Quiescence comes into play with home growers typically when contaminants or poor
environmental controls come into play. A lot of the time when growers are beginning a
project, sometimes contaminants will get into their projects alongside the spores or
mycelium they’ve inoculated their bags with. The mycelium will grow fine, then suddenly
stop, for no apparent reason. If contaminants are present, the mycelium may have
detected the invader and rather than using energy to try to outcompete the invader, the
mycelium will ‘shut down’ in an attempt to outlast the invading life. This can also happen
when bags go through a ‘break and shake’ then never recover, if there was a
contaminant present and the mycelium was broken up and now becomes aware of the
contamination spread throughout the bag or jar, the mycelium will go dormant and stop
growing. This can also happen if temperature or humidity is not adequate for the
mycelium, when the temperature is too hot or cold rather than putting energy into trying
to grow into the inhospitable environment the mycelium will instead go dormant and try
to wait for the environment to adjust. Both of these scenarios are important when
growing, understanding what can lead to mycelium growing well then suddenly stopping
or sometimes disappearing can help growers avoid issues on future projects.

Rhizomorphic

Our next term is rhizomorphic, which is a type of mycelium growth which most growers
think is ideal when working on indoor cultivation. Rhizomorphic growth is very easy to
identify, it presents as ropelike tendrils of growth, spreading quickly over agar or grain. A
lot of growers prefer this type of growth over ‘tomentose’ growth, which presents as a
fuzzy growth, moving in a radial pattern along the available nutrients. Rhizomorphic
growth has its benefits, namely being able to sequester it easily on agar, the tendrils of
growth give an obvious speed indication, allowing the grower to sample the farthest
reaching sections of growth and continue growing these sections out, hoping for a fast
growing mycelium based on the speed of the tendrils. Rhizomorphic growth also allows
contaminants to be easily identified, the ropes of growth appear strong and any
contamination will be easy to see compared to the thin ropes of growth present.

Rhizomorphic growth does have its downsides however. As rhizomorphic favors growth
that is narrow in its expansion, growing outwards and outwards, this growth leaves
behind areas of available nutrients, favoring expansion over consumption. This growth
also has less genetic variation in the tendrils, which if working in a controlled
environment increases the probability that the environment that is being given may not
favor the few genetic lines that are present in the small area of mycelium being
transferred. Rhizomorphic growth is something that can indicate strong growth of a
genetic lineage, however it is not always necessary for a lineage to be strong, and it can
actually cause more issues compared to growth that is more spread and varied. If
you’re looking to get rhizomorphic growth with your projects, certain blends of nutrition
can favor this growth. These nutrients are what we use for our AGAR PRODUCTS,
giving a better chance of finding fast, rhizomorphic growth when using our agar!

Senescence

Senescence is our last term for this article. Senescence is a term associated with
genetic and breeding work, it is an irreversible decline and degradation of a genetic line
due to age or dilution. Typically this will not effect any home growers or small genetics
vendors who are not repeatedly transferring their genetic material without going back to
spore or clone material. For larger sellers or breeders, senescence can be a killer of
genetic material, if a grower takes a sample from agar and puts it to liquid culture, then
uses that liquid culture to make more liquid culture, then that subsequent liquid culture
is used to make more liquid culture, and so on, eventually the genetic material will begin
to degrade. This can lead to slow growth, mycelium dying off, mycelium being weak, or
mycelium being unable to produce fruits.
Avoiding senescence is extremely easy luckily! All that a grower needs to do is grow out
fruits from their cultures, then take clones of that material, or spores and restart their
culture process. Even with the ease of avoiding senescence, larger vendors sometimes
do not take the time to verify their cultures or grow them out, making senescence
something to look out for when purchasing from large liquid culture vendors. We have a
list of RECOMMENDED VENDORS all of which take steps to avoid this happening
with their products!