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bakedbeings
orbiter of truth


Registered: 09/01/20
Posts: 4,218
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sorry...another senescence question
#27540500 - 11/12/21 12:32 PM (2 years, 6 months ago) |
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forgive me if this isnt "advanced"...im posting here because i want to avoid dumb answers if possible. ive been researching slants a lot and its making me question some stuff that ive always taken for granted
at some point i read an explanation of senescence and the sentence that stuck in my head was "a cell can only divide so many times" which got me thinking that senescense simply limits the volume of myc that can grow from x amount, but what ive been reading about slants makes me think that the only limit on growth is time, which refridgeration mitigates
so to put my question in practical terms, if i was doing g2g transfers, is senescense the limit on how many jars the myc can colonize before it cant physically stretch any further? or on how many it can colonize before it runs out of time?
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CreonAntigone
Stranger

Registered: 05/30/21
Posts: 2,971
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Re: sorry...another senescence question [Re: bakedbeings]
#27540590 - 11/12/21 01:33 PM (2 years, 6 months ago) |
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Quote:
Bakedbeings said:
at some point i read an explanation of senescence and the sentence that stuck in my head was "a cell can only divide so many times" which got me thinking that senescense simply limits the volume of myc that can grow from x amount, but what ive been reading about slants makes me think that the only limit on growth is time, which refridgeration mitigates
There is a limit to how much myc can grow and live in a limited resource like a slant, yes. But the problem is that things change entirely if you're introducing that myc to a new resource. So let us say you have an old slant but now you drop it into a fresh jar of LC. It has a whole new batch of resources to eat and can start again. The same principle with grain to grain transfers.
Think of this from a biological perspective. Do you think mushrooms would survive very long if their mycelium could only grow a little bit and no further? In the wild mushrooms benefit greatly from being introduced to new places. It helps them when, for example, animals trample them and then their hooves might smear it on an entirely new place it hasn't colonized yet.
Basically there is senescence, but there's the opposite phenomenon of cultural expansion where essentially mushrooms in a new environment will start all over again and make a lot of new mycelium, eliminating the threat of senescence. The ability of mushrooms to expand merely from mycelium varies greatly with species and probably with 'strain' too. But a good cultivator can manage it with any species. It's my opinion that a culture could live indefinitely if you keep transferring it to appropriate new slants. The original culture and slants will degrade though so you may need to essentially 're-isolate' the myc by doing agar transfers all over again.
Quote:
so to put my question in practical terms, if i was doing g2g transfers, is senescense the limit on how many jars the myc can colonize before it cant physically stretch any further? or on how many it can colonize before it runs out of time?
I think your attitude is slightly off. A better way to think of it: senescence is the degradation of one culture in particular. If a slant has been colonized for a long time, senescence is when the myc has stretched so far it doesn't have the energy or resources to stretch further, nor does it really have a need to.
However, even if a culture is degrading that doesn't necessarily mean it cannot find new life in a grain to grain transfer. So you really are asking two questions: one is, how long can a culture live (and how refrigeration impacts this); second, how much can an old culture be expanded with grain to grain? As to the second question, people on this forum often find that with the right practices they can revive even long-dormant cultures. You'll be interested to read the thread on this forum about expanding mycelium from dehydrated pieces of grain spawn.
Seriously, read that thread and it will probably answer you questions. You can then attempt a similar experiment yourself with your oldest cultures.
Edited by CreonAntigone (11/12/21 01:34 PM)
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bakedbeings
orbiter of truth


Registered: 09/01/20
Posts: 4,218
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Re: sorry...another senescence question [Re: CreonAntigone]
#27541351 - 11/13/21 05:42 AM (2 years, 6 months ago) |
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anybody else?
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QM33
(NOT A PUPPET!) β€β€β€β€β€



Registered: 04/09/20
Posts: 4,739
Loc: Oregon
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Re: sorry...another senescence question [Re: bakedbeings]
#27541752 - 11/13/21 12:03 PM (2 years, 6 months ago) |
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bakedbeings
orbiter of truth


Registered: 09/01/20
Posts: 4,218
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Re: sorry...another senescence question [Re: QM33]
#27543111 - 11/14/21 01:57 PM (2 years, 6 months ago) |
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Quote:
QM33 said: https://www.shroomery.org/forums/showflat.php/Number/24625937/fpart/all
awesome thread thank you. i still dont understand it but now at least i know i never will
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PTreeDish


Registered: 04/22/18
Posts: 353
Last seen: 1 month, 3 days
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Re: sorry...another senescence question [Re: bakedbeings]
#27546301 - 11/16/21 08:33 PM (2 years, 5 months ago) |
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Senescence is a gradual breaking down of biological function. It can happen for many reasons, but generally, the longer you keep the same cell-line going and replicating, the more genetic mutations will accumulate and ultimately cease one or more biological processes necessary for the fungi to function.
There's a good paper on this that uses Neurospora to talk about senescence in fungi: https://academic.oup.com/femsle/article/280/2/135/545808
> if i was doing g2g transfers, is senescense the limit on how many jars the myc can colonize before it cant physically stretch any further? or on how many it can colonize before it runs out of time? There is no universal hard limit given the variable nature of senescence, but it would eventually happen. You should run an experiment and share it with us all. That would be really interesting.
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el gordo
not the youtube one



Registered: 09/05/20
Posts: 108
Last seen: 2 months, 1 day
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Re: sorry...another senescence question [Re: PTreeDish]
#27546542 - 11/17/21 01:41 AM (2 years, 5 months ago) |
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dont worry too much about that... i had cloned all kind of mushrooms from the supermarket and always got nice stuff, did grain to grain with bought shitake spawn that the seller told me specifically that were 4th transfer and will no work...still working with the same strain and inoculated hundreds and hundreds of bags giving impressive flushes always. Also ask yourself how its possible that vendors sells the same living tissue strain for many years, how is that they not suffer from senescense? i believe that we're calling senescense to things that theyre not. some years ago was alot of talk in the cannabis world about clones and senescence degeneration, this claim came mostly from seed sellers wanting to make the people get rid of the cuts they hoarded and buy new seeds from them.the fact is that theres cuts that have 30-40 years and are exatly the same as day 1, mushroom cultures stored since the 50's, theres rosebush cuttings that are circulating since the 16th century, same or longer with fruit trees, wine vines, etc...
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MycoWeek
Elementary Student




Registered: 07/05/21
Posts: 674
Loc: USA
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Re: sorry...another senescence question [Re: CreonAntigone]
#27551643 - 11/20/21 08:03 PM (2 years, 5 months ago) |
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Quote:
CreonAntigone said: Basically there is senescence, but there's the opposite phenomenon of cultural expansion where essentially mushrooms in a new environment will start all over again and make a lot of new mycelium, eliminating the threat of senescence. The ability of mushrooms to expand merely from mycelium varies greatly with species and probably with 'strain' too. But a good cultivator can manage it with any species. It's my opinion that a culture could live indefinitely if you keep transferring it to appropriate new slants. The original culture and slants will degrade though so you may need to essentially 're-isolate' the myc by doing agar transfers all over again.
When you say new environment, does it mean new substrate? or it needs to be nutrient sources like grains?
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dyel



Registered: 10/15/21
Posts: 920
Last seen: 2 months, 2 days
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Re: sorry...another senescence question [Re: MycoWeek]
#27585882 - 12/18/21 08:28 AM (2 years, 4 months ago) |
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total noob here but... It's the world biggest living organism a honey mushroom that is probably thousands of years old?
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PTFer
All Around Dumb Fuck


Registered: 10/18/21
Posts: 104
Last seen: 1 day, 3 hours
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Re: sorry...another senescence question [Re: bakedbeings]
#27588649 - 12/20/21 06:23 PM (2 years, 4 months ago) |
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Some info from Stamets, "Growing Gourmet and Medicina Mushrooms"
definition - senescence: the state whereby a living organism declines in vigor due to age, a consequence of limitation of cell divisions due to errors in replicating DNA.
since g2g is basically cloning myc -
Many people ask, βWhat is wrong with just cloning a nice-looking specimen from each crop of cultivated mushrooms to get a new strain?β Although morphological traits can be partially selected for, senescence factors are soon encountered with each subsequent clone, a condition known as replicate fading. Generating cultures in this fashion is a fast track to genetic demise, quickly leading to loss of vigor and yield. By not returning to stock cultures, to young cell lines, one goes further downstream one linear chain of cells. Mushrooms, like every sexually reproducing organism on this planet, can generate a limited number of cell divisions before vitality falters. Sectoring, slow growth, anemic mushroom formation, malformation, or no mushroom formations at all, are all classic symptoms of senescence. Although senescence is a frequently encountered phenomenon with cultivators, the mechanism is poorly understood. (See Kuck et al. 1985.)
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