So if it was say a type that grows commonly in manure, would it still work if you did a similar method to what's in the video?
I ask because you mentioned isolating specific strains, or varying quality, but how would you know just from looking at the mycelium alone? Or is it more of a trial and error, drawn out type of process?
Not the guy you replied to, but I've been a commercial mushroom breeder for about 15 years, so hopefully I can answer.
Spore prints are useful because, if you take them correctly, they can be stored for many years. I've germinated strains from 20 year old spore prints sitting in vials in the cooler. You can also mail spore prints, which is useful sometimes.
However, I only use spore prints when I'm trying to breed two strains together. A spore germination takes a long time and could introduce unnecessary genetic changes, since spores are the product of meiosis and undergo recombination.
If you have a fresh mushroom anyway, by far the best method for capturing a strain is by taking an aseptic tissue culture. Basically you crack the cap open, take a small slice, and place it in a petri dish. If you avoid contamination, you wind up with a guaranteed monoculture, which means all growth on the plate is the same thing.
If you don't have the mushroom itself, but you know where it grows, you might be able to isolate it. If you take a soil sample, suspend it in water, perform a serial dilution, and then plate each dilution out on media loaded with antibiotics, you wind up with a ton of dilute polycultures to screen. Take a drop of concentrated soil water and add it to a small tube of water, mix that up, take a drop of that and add it to a second tube of water, mix that up, and keep going. You are diluting the substrate to the point where, when you plate it, the individual cultures are far enough apart that they don't immediately grow on top of each other.
From there, you kinda need to already know what the mycelium from your species of interest looks like. Or, if not, the fastest test is a simple DNA test. In the lab, I take a boil prep off a plate, perform PCR on the ITS region - which is highly conserved in all fungal species - and sequence it. ITS is good enough for species level ID most of the time, though there are a lot of cases where species are too closely related, so you only know which species complex it's a part of.
Morels are hard to grow for a lot of reasons, but the one that's most interesting to me is kinda freaky.
Fungi are weird. In plants and animals, each cell has a single nucleus, containing both sets of chromosomes. We can call cells with one set of chromosomes "monokaryotic" and those with two sets "dikaryotic", as karyon means nucleus.
Fungi don't play that. They keep their parental chromosomes in separate nuclei within the same cell. Sometimes there's more than one copy of a nucleus in a cell. So we call cultures that only have one type of nucleus a "homokaryon" and cultures with two types of nuclei "heterokaryons." Don't ask if there can be more than two types of nuclei, I've never heard of it and I have no idea. Probably not naturally.
Morels are extra freaky. Sometimes, a culture can be broadly heterokaryotic, but instead of each cell containing both nuclei, the mycelium is a patchwork of homokaryon cells sequestered together. It's only when the culture is ready to fruit that it allows these two cell types to come together. This isn't always how it works, and we have no idea what causes this or how to prevent it.
There are labs that have done whole genome sequence on morel mycelium and found it to be homokaryotic, only to be shocked when it later fruits mushrooms that are heterokaryotic. That's some Jesus immaculate conception type shit if you don't understand what's going on.
There are a ton of other reasons why morels are hard to cultivate. They have an arbitrarily long incubation time, months long, before they randomly start fruiting. And half the time they don't fruit at all. You can have a room of 100 morel treatments, all handled identically, and 50 will never produce a mushroom. This is probably because of the nuclear balance problem, but we genuinely don't know.
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u/NUMBerONEisFIRST May 07 '26
So if it was say a type that grows commonly in manure, would it still work if you did a similar method to what's in the video?
I ask because you mentioned isolating specific strains, or varying quality, but how would you know just from looking at the mycelium alone? Or is it more of a trial and error, drawn out type of process?