Iuval Clejan

Is the talk available for free? What is the link, please?

Is it free to watch this talk? Or does it cost? What is the link, please?

More from my mycologist friend:
"There is increased susceptibility for a couple reasons, one of which you mentioned. When the mycelium is actively established and has a good amount of substrate colonized, it acts as a large nutrient source, as well as occupied territory. This larger established mycelium has extra resources to spend defending itself, and it has also partially depleted the nutrients where it is growing, reducing the aggressiveness of possible competitors.

When you slurry or chip that mycelium, it introduces a lot of wounds, releases cell contents which Trichoderma finds delicious, and creates a substantial lag period where that mycelium will have to take time to recover from the trauma, and eventually reconnect. You have taken that large colony and split it into many smaller ones which aren't going to be as durable until they actually reconnect.

Trichoderma is a mycoparasite, and will specifically wait for moments like that when mycelia is weak to take hold. Once it consumes enough mycelium, it will often gain enough momentum to take over the whole substrate.
A similar depletion also happens during fruiting, when the mycelium exhausts itself and its nutrient stores to produce fruitbodies, which is often why Trichoderma shows up during or after fruiting"

John Weiland wrote:

Iuval Clejan wrote:    

1)   I suppose you can put them on agar plates and keep transferring away from the damage. But that is a pain, and then you need to expand again with substrates I don't have.

2)   Also using what is available locally as much as possible?.

3)  .... I worked in a C.elegans lab for 4 years studying senescence...
 

For #1, yes....and one can really never tell if the "fresher" looking growth of the mycelium has the least amount of damage.  Senescence is a strange and enigmatic phenomenon....we all senesce and die at some point.  The C. elegans (#3) "dauer larvae" are a stage of that nematode that can be somewhat thought of as a metabolically active spore stage....not taking in food, but using internal reserves for movement until proper environmental cues allow for reversal of this state and they become not only active feeders again, but almost "age-reversed".  [You can see why some investigation into this phenomenon is being pursued as a veritable 'fountain of youth'!]  Most senescent programs of change, once initiated, tend to progress towards death of the cells, the tissue or the organism as a whole.  How this happens in fungi is likely as complicated as in other systems.

As for #2, agreed....in an ever-changing ecosphere, even if needing to relinquish some 'control' over timing and purity of what you are hoping to cultivate, by constantly selecting from that local biome, you are retrieving isolates of the desired species that may have changed, but hopefully in a manner more adapted to the changes within that biome.  At the risk of doubling the work-load, perhaps some version of both lab-style cultivation followed by spore/mycelium dispersal outside to a most-favored earth-based substrate would be worth trying....

Ian Påf wrote:

The chapter is unclear on whether hardwood logs are ephemeral... they're somewhere between entire forests (which support the non-senescing Armillaria) and dung piles (which support senescing Ascomycetes). But there isn't any research as far as I can tell that indicates that fungi living on hardwood logs senesce. I don't have a great understanding of the molecular biology of senescence but it seems that the molecular aspects of senescence are accumulated with age rather than running out of food.

Accumulated with age, yes, but also due to not dividing or growing. If cells continue to divide or grow, as they do when the mycelium runs, the damage dilutes. The exception is certain germ cells like spores, which either have very good repair mechanisms, or a very slow metabolism, which produces little or no oxidative damage, or else get selected against by natural selection if they have damage. I worked in a C.elegans lab for 4 years studying senescence...

Anyways, of course I believe academic publishers provide valuable services to society and that it's okay to restrict access to knowledge for people with less money, and would never ever suggest that you access this chapter for free by searching for "Why do some fungi senesce and others do not" on a website like libgen.........

Thanks, but the search turned out empty. Interesting website/project. I wish I could pay just for that chapter, instead of buying the whole book.

I think it's just that you pull (or spray) plant weeds, but there's nothing you can really do to remove competitor fungi.

I suppose you can put them on agar plates and keep transferring away from the damage. But that is a pain, and then you need to expand again with substrates I don't have.

Permaculturists try to use methods for growing plants that don't require manual or chemical control of competitors, and I think this concept needs to be applied to mushrooms as well. How, I don't know.

Also using what is available locally as much as possible?

I'll respond to the rest of your reply later, but for now, what do you think of this reply from my mycologist friend?:
I don't recommend chipping logs. Typically, if they've spent time outdoors as is standard, they have the mycophagic mold Trichoderma. It will ruin a grow space.
Logs are not a reliable or sustainable source of mushrooms without regular labwork to inoculate them, sort of a one-session thing. This is because of contaminants"
I asked him what he thought of chipping logs while the mycelium is running, as innocuant for new logs. A variation on putting the mushrooms in a blender

I think it's just that you pull (or spray) plant weeds, but there's nothing you can really do to remove competitor fungi. Permaculturists try to use methods for growing plants that don't require manual or chemical control of competitors, and I think this concept needs to be applied to mushrooms as well. How, I don't know.

Ian Påf wrote:Plenty of natural methods generate new mycelia from spores rather than expanding old ones. The Japanese used to stack Shiitake logs in a 'log cabin' style, with fruiting logs on top and new logs on bottom, so that spores fall onto and inoculate the lower logs. Slurries can be made with just spores by letting mushrooms soak in water and then removing the mushrooms. Another of Stamet's books, Mycelium Running, goes into depth on 'natural' growing methods, whereas Growing Gourmet and Medicinal Mushrooms mostly focuses on lab methods.

That sounds like a good idea too, except for the labor of adding new logs on the bottom.

Methods that do simply propagate old mycelia have been frequently used with success also. The French would inoculate compost/manure with Agaricus by mixing in spent substrate.

But then came Louis Pasteur and they decided to depend on labs... I wonder if I can do the same with logs.

I've also had some success with taking stem butts of mushrooms and laying them on moist cardboard, which is soon colonized by mycelium. This cardboard can then be used to make spawn plugs for logs (see again Mycelium Running). This requires an intermediate substrate, but it can be produced sustainably.

Do you sterilize the cardboard first?

I do wonder whether senescence is really a concern - after all, one genetically-individual Honey Fungus (Armillaria ostoyae) covering over 2,000 acres has been identified in Oregon (http://botit.botany.wisc.edu/toms_fungi/apr2002.html). Some fungi senesce while others are potentially immortal, and as far as I can find, most fungi known to senesce belong to the Ascomycete division, with the only Basidiomycete known to senesce being Heterobasidion parviporum, a non-edible plant parasite (Basidiomycota, as John noted, contains most cultivated species). Fungus species are more likely to senesce if they are adapted to ephemeral substrates, such as dung or insects (https://www.cambridge.org/core/books/abs/evolution-of-senescence-in-the-tree-of-life/why-some-fungi-senesce-and-others-do-not/FA8ED9EF1098C62C7225CF67D364E4CA). I can't find any information either way about whether commonly cultivated Basidiomycetes senesce. The idea of senescence justifies Stamet's company charging large sums for 'young' cultures, but at the same time, Stamets is a leading expert on cultivation.

Money corrupts in a dose-dependent manner... Are hardwood logs considered ephemeral? Is the idea of that book (which I won't buy yet because I might be able to get it for free from a friend or library) that running out of food sends out a molecular signal for both senescence and sporulation, because it's adaptive to focus energy on running the mycelium or sporulation, and starvation favors sporulation as a survival strategy, rather than investment in the mycelium? Is the molecular signal reversible for the mycelium upon introduction of new substrate? Or only for the spores?

Either way, the biggest challenge to 'natural' cultivation methods is wild competitor fungi. Therefore, you'll have best success using natural methods with fungi like Wine Caps and Oysters, which are strong competitors. Using fresh substrate will help reduce competitors.

I plan on oysters. I wonder why competitor fungi are more of a problem for cultivating edible fungi than competitor weeds are for cultivating edible plants. Is it because of the microscopic scale, so that by the time you know you have a problem with competitor fungi, it is already late in the game, whereas with weeds you can tell early on?

It is also possible to grow mushrooms using sterile methods without having access to all of the fancy things that commercial labs have, but you will lose more spawn to contamination. Glass petri dishes, mason jars, and a pressure cooker could get you started. For agar, I use agar-agar powder from a local Asian grocer with dried malt extract from a local brewing supply store (see Growing Gourmet and Medicinal Mushrooms for the proportions, I can't recall off the top of my head), though I realize these stores are harder to find in more rural areas.

Yes, I still have my petri dishes, and will look for a source of agar (I had some from my colleague before I moved).

I have also heard of people making glove boxes from plastic totes, etc.. You will still likely do best with species that are strong competitors without having expensive, synthetic filters. Personally, I've had some, but limited, success with sterile cultivation as I can't afford HEPA filters.

Thanks for your help!

That sounds like a great idea! I assume you have had good success with it? I would worry that the mycelium from the spores would still need to find the correct mating type, so maybe not as good of a yield from that. I'm hoping there will be no stagnation of the clones as long as the fruit is harvested in a timely manner. The whole telomere shortening thing (for other organisms) was supposedly not directly because of telomere shortening , but because cultures ran out of nutrients and stressed the organisms (sometimes also causing shortened telomeres).

Joseph Lofthouse wrote:My favorite inoculation method is to put this year's fruits into a blender with water to make a slurry. The slurry is then dumped on to suitable habitats. That is both cloning the original fruit, and distributing new spores to keep the culture from stagnating.

Thanks for that. I had built a lab and a positive pressure hood (with hepa filter) in the place I used to live at, and I don't know if I have it within me to build it again, but this is perhaps a good intermediate. I'm still wanting to pursue the option of propagation without sporulation or freezing of cultures, if possible. Supposedly the Rhizopus species (Oligosporus and Oriziae) can persist in some places like Indonesia, without needing to be frozen, but maybe they do sporulate before they are propagated. There was some speculation by the tempeh dude (forgot his name) that those environments are just so full of Rhizopus spores and they are so suited to the local environment that nothing else can compete. Perhaps this can be done with other species in other environments?

John Weiland wrote:Log culture sounds pretty cool and likely needing a fair amount of deep knowledge on such culture that you may or may not have access to.  I guess in the interest of being a curator of sorts, I would approach this using a bit of modern (but not too modern) technology, with a general plan not too different from seed saving.  Just guessing, but I think many basidiomycetes, which would encompass many if not most edible fungi (?) form sclerotia or a dormant resting stage when dried in agar.  If you could initially purchase glass (Kimax/Pyrex) petri plates, these are autoclavable/sterilizable and can be re-used many times before they crack or require discarding.  Make sure to purchase with a glass lid. Find agar from numerous sources, Carolina Biological Supply being one, but I suspect food-grade agar would do.  There will be methods out there for making essentially "wood tea" using the wood that normally hosts the fungus of interest.  After removing the wood pieces, melt agar into the liquid to about 15% concentration (15 grams agar per litre of wood tea -You may find recipes that vary from this or use adjuvants that assist fungal growth in this  medium).  Pour enough of the molten agar mixture into a sterile glass petri dish to generously cover the bottom surface, replace the sterile lid on the plate, and then let cool to harden the agar.

When cool and ready (usually the next day), open the lid on a plate rather briefly and transfer a clean-as-possible piece of the fungus in question to the middle of the plate and return the lid to the plate as soon as possible, preferably without setting the lid down on a surface in the process.  The plate can now be stored at room temperature in a similar dark room to where you might grow a mushroom kit.  If your fungus likes this substrate, it will start to grow hyphae outward from the piece and running along the surface of the agar.  If really fortunate, it will cover the entire plate in a few days to a few weeks.  Once this occurs, you could use some sort of food dehydrator to dry down the entire culture....fungal mat + agar....until it is like a crispy wafer.  Dry at room temperature...no heat!....to retain viability of the mycelium as it is drying.  Remember, the lid on the Petri dish simply sits atop the plate and therefore allows some air transfer between the culture and the outside air without permitting wholesale contamination of the culture....this advantage allows you to leave the lid on when desiccating the fungal/agar mat so it remains as free from contaminants as possible.  The 'wafer' can now be chopped up with a scissors or cutting tool into small pieces which can be stored in a separate, clean petri dish + lid (no agar) which is sealed with tape and stored in a freezer.

To test success of the procedure if you obtain a fungal mat and follow through to dried pieces, simply pour a new petri plate with "wood tea agar", let it harden as before, then transfer a small piece of your dried wafer to this agar surface and see if the same growth occurs.  If it does grow, then you know that your fungus/mushroom survived the procedure.  You can take pieces out of the freezer at different times throughout the year to test again for 'viability' of your stored culture.  If it starts to decline (i.e. too many "dead" pieces), then it may be worth dumping several pieces out on one plate.....and if something grows, then take this new fungus back to culture on wood/log pieces.  It's well known that culturing too long on agar can cause a fungus to lose certain characteristics, so it's best to use it only as one method and have parallel stocks in other substrates (i.e., log culture, soil culture, etc.).

Anyway, just one possibility....Good luck!

Doesn't defeat your purpose. You would be doing the work, not a commercial lab.

Probably lots of factors such as yield, available space, using up the logs, effort/hours that favor newer logs/mushrooms over older ones, if it's just for you personally, versus a business enterprise....

It defeats my purpose in the sense of all the tools and materials that I don't have on the land and that are ultimately dependent on an unsustainable industrial system, not in terms of the work (which the industrial system minimizes and trades off for all those unsustainable materials and practices). I have lots of trees, I already have a chainsaw (and eventually I could get a pull saw, but for now I am making that tradeoff), I don't have straw or enough sawdust.

So I don't have to have huge yields, although it would be nice to sell some mushrooms to neighbors and perhaps at the farmer's market. I am not 100% opposed to a lab either, though I'd prefer if I could build it on the land. It's a question for now: how much can be done without the lab (except perhaps initials spawn)? What is the best way to do it?

With plants, people can save seeds for annuals, or grow perennials, not having to depend on seed producing companies year after year. What about mushrooms? How long can they be grown and what are the best species and methods for keeping them going for the longest possible time in a outdoor log culture in mid TN? I know people used to grow mushrooms without labs, in Japan, in France, and probably other places. My question is more specific to outdoor log culture (which existed in Japan and maybe still does).

So is it possible to save some of the harvest once the logs are spent, and just transplant to other logs? Or do I need to save spores, and then do I have to expand them in intermediate (non log) substrates, which defeats my purpose? Or can I cut out clonal tissue from mushroom caps and use that as innoculant for the next batch? Or maybe get it while it's still running mycelium and transplant that as pieces of a log?

I have read Stammet's book (Growing Gourmet and Medicinal Mushrooms), where he does mentions some natural techniques that don't rely on labs, but I wonder if this can keep a culture going indefinitely. He claims senescence will set in eventually without sporulation, but maybe that's only the case if the log substrate is spent or if the growth is stunted in some way (a FB friend of mine who is a mycologist dared challenge Stammets on this).