u/Scrybal commented on a comment I made, quoting my: “dice roll of spore germination”
Their comment: “ I've read a lot of posts and comments on the sub and have literally never come across this phrase. I have no idea what to make of it. I didn't even know that it was possible to have a stagnant strain. What is a stagnant strain? “
Spore germination is absolutely a dice roll, and a huge one with multi-variant possibilities, at that. Not just genetically when two spores do actually mate... but also related to the sterility of the water that multi-spore syringes have spores suspended in... and then there is the fact that you can have a clump of spores and none of the spores touching each other (without aid of zig-zag inoculation loop across petri dish) that just simply dont germinate with each other and just stay a clump of spores.
When I say stagnant strains I literally mean spore germination that leads to growth characteristics and/or genetic issues that cause its metabolism to cease, or slow to the point of competitor contaminants taking over uncolonized nutrients before the slowed or stalled or ametabolic mycelium)
The Mushroom Cultivator, Stamets and Chilton explains (page 5-14) the following related to lifecycle of basidiomycetes:
In the life cycle of the mushroom plant, the fruitbody occurs briefly. The mycelial network can sit dormant for months, sometimes years and may only produce a single flush of mushrooms. During those few weeks of fruiting, the mycelium is in a frenzied state of growth, amassing nutrients and forming dense ball-like masses called primorida that eventually enlarge into the towering mushroom structure. The gills first develop from the tissue on the underside of the cap, appearing as folds, then becoming blunt ridges and eventually extending into flat, vertically aligned plates. These efficiently arranged symmetrical gills are populated with spore producing cells called basidia.
From a structural point of view, the mushroom is an efficient reproductive body. The cap acts as a domed shield protecting the underlying gills from the damaging effects of rain, wind and sun. Covering the gills in many species is a well developed layer of tissue called the partial veil which extends from the cap margin to the stem. Spores start falling from the gills just before the partial veil tears. After the partial veil has fallen, spores are projected from the gills in ever increasing numbers.
The cap is supported by a pillar-like stem That elevates the gills above ground where the spores can be carried off by the slightest wind currents. Clearly, every part of the mushroom fruitbody is designed to give the spores the best opportunity to mature and spread in an external environment that is often harsh and drastically fluctuating. As the mushroom matures, spore production slows and eventually stops. At this time mushrooms are in their last hours of life. Soon decay from bacteria and other fungi sets in, reducing the once majestic mushroom into a soggy mass of fetid tissue that melts into the ground from which it sprung.
Most mushrooms produce spores that are uninucleate and genetically haploid (1N). This means each spore contains one nucleus and has half the complement of chromosomes for the species. Thus spores have a "sex" in that each has to mate with mycelia from another spore type to be fertile [thus to germinate] for producing offspring. When spores are first released they are fully inflated "moist" cells that can easily germinate. Soon they dehydrate, collapsing at their centers and in this phase they can sit dormant Through long periods of dry weaTher or severe drought. When weather conditions provide a sufficiently moist environment, the spores rehydrate and fully inflate. Only then is germination possible.
Spores within an individual species are fairly constant in their shape and structure. However, many mushroom species differ remarkably in their spore types. Some are smooth and lemon shaped (in the genus Copelandia, for instance); many are ellipsoid (as in the genus Psilocybe); while others are highly ornamented and irregularly shaped (such as (hose in Lactarius or Entoloma}. A feature common to the spores of many mushrooms, particularly the psilocybian species, is the formation of an apical germ pore.
The germ pore, a circular depression at one end of the spore, is the site of germination from which a haploid strand of mycelium called a hypha emanates. This hypha continues to grow, branches and becomes a mycelial network. When two sexually complementary hyphal networks intercept one another and make contact, cell walls separating the two hyphal systems dissolve and cytoplasmic and genetic materials are exchanged. Erotic or not, this is "mushroom sex". Henceforth, all resulting mycelium is binucleate and dikaryotic. This means each cell has two nuclei and a full complement of chromosomes. With few exceptions, only mated (dikaryotic) mycelia is fertile and capable of producing fruitbodies. Typically, dikaryotic mycelia is faster running and more vigorous than unmated, monokaryotic mycelia. Once a mycelium has entered into the dikaryophase, fruiting can occur shortly thereafter. In Psilocybe cubensis, the time between spore germination and fruitbody initials can be as brief as two weeks; in some Panaeolus species only a week transpires before mushrooms appear. Most mushroom species, however, take several weeks or months before mushrooms can be generated from the time of spore germination.
Cultivators interested in developing new strains by crossing single spore isolates take advantage of the occurrence of clamp connections to tell whether or not mating has taken place. Clamp connections are microscopic bridges that protrude from one adjoining cell to another and are only found in dikaryotic mycelia. Clamps can be readily seen with a light microscope at 100-400X magnification. Not all species form clamp connections. (Agaricus brunnescens does not; most all Psilocybe and Panaeolus species do). In contrast, mycelia resulting from haploid spores lack clamps. This feature is an invaluable tool for the researcher developing new strains.
Two dikaryotic mycelial networks can also grow together, exchange genetic material and form a new strain. Such an encounter, where two hyphal systems fuse, is known as anastomosis. When two incompatible colonies of mycelia meet, a zone of inhibited growth frequently forms. On agar media, this zone of incompatibility is visible to the unaided eye.
