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jesuisravi
The Old Noob



Registered: 06/24/15
Posts: 260
Loc: Midwest USA
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senescence.
#22030579 - 08/01/15 09:02 PM (8 years, 5 months ago) |
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Taking the fruit of a particular union of 2 mate-able monokryotic strands of mycelium--because you like the way it looks, for instance, or tastes--and then inoculating spawn with a liquid culture made up of the atomized body of said fruit, i.e., cloning it, then mixing that spawn to bulk and growing thousands of fruits each having the clone-worthy characteristics--this process can only be repeated so often before the clones developed from it cease manifesting the traits of the master specimen.
If I have this right so far, then let me ask this: How many times can the process be carried out with satisfactory results. Say with cubes or with reishis? Is this decline (?) species specific. Maybe cubes are quicker to fall away from type, than reishis? Or, maybe reishis are not subject to this kind of decadence at all?
Is there anyway to beat this degradation?
-------------------- Most of my beliefs I acquired from my father and from John Wayne, and anything that wasn't ultra tough and ultra cool was to me ultra embarrassing. In fact, I lived in a state of near continuous embarrassment, never measuring up to the ridiculous standards I had accepted without question, applied to a framework of expectations neither I nor anyone else could meet.--J C Amberchele almost nothing important that ever happens to you happens because you engineer it. Destiny has no beeper; destiny always leans trenchcoated out of an alley with some sort of 'psst' that you usually can't even hear because you're in such a rush to or from something important you've tried to engineer. ” ― David Foster Wallace, Infinite Jest
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Kizzle
Misanthrope


Registered: 08/30/11
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There's no specific time or number of transfers that will lead to senescence. It's predictable only in the sense that it will always eventually happen.
However senescence is usually indicated by a drop in yield. Loss of other traits like colonization speed and appearance can occur from a different phenomenon (although they can eventually happen from senescence as well) called strain instability which tends to be a trait of the particular strain.
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jesuisravi
The Old Noob



Registered: 06/24/15
Posts: 260
Loc: Midwest USA
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Re: senescence. [Re: Kizzle]
#22033191 - 08/02/15 12:09 PM (8 years, 5 months ago) |
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So, eventually there will be a necessity to go back to multispore generated fruits to get another candiate for cloning? I wonder if this would ever be a problem for a home cultivator--someone who is not putting commercial stress on his fruiting system.
-------------------- Most of my beliefs I acquired from my father and from John Wayne, and anything that wasn't ultra tough and ultra cool was to me ultra embarrassing. In fact, I lived in a state of near continuous embarrassment, never measuring up to the ridiculous standards I had accepted without question, applied to a framework of expectations neither I nor anyone else could meet.--J C Amberchele almost nothing important that ever happens to you happens because you engineer it. Destiny has no beeper; destiny always leans trenchcoated out of an alley with some sort of 'psst' that you usually can't even hear because you're in such a rush to or from something important you've tried to engineer. ” ― David Foster Wallace, Infinite Jest
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Kizzle
Misanthrope


Registered: 08/30/11
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If you only clone once and keep that culture to use as a master culture it's not really an issue. You can just go back to the master culture. Of course you'll have to keep the master refrigerated if you want to keep using it for long periods of time without degradation.
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matsc
Stranger



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Re: senescence. [Re: Kizzle]
#22034145 - 08/02/15 04:04 PM (8 years, 5 months ago) |
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Senescence is an odd thing, and very very difficult to pin down with any specificity. Even if you had two batches cloned from the same fruit, treated identically, they may fade at differing rates.
Eventually, over time, genes that become "useless" to the organism will become lost. Sometimes they're mutated and there is no longer a selective pressure to keep them around. Some times recombination will scramble a locus or two. Basically you've taken a wild organism and planted it in a very artificial environment with a very different set of conditions that are "optimal". As the organism adapts to this new local, it may well lose the traits that made you desire it in the first place.
I run into this pretty often in lab, studying plant pathology. We take a wild plant pathogen fungus, and after several serial platings, it loses its pathogenicity. Basically because rather than having to optimize itself for living in/on a plant and deriving nutrients from there, its now growing on agar plates with a strange mix of salts and supplements. Why keep the genes for plant life if they are no longer useful?
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Rictus
Stranger

Registered: 06/08/15
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Re: senescence. [Re: matsc]
#22035035 - 08/02/15 07:44 PM (8 years, 5 months ago) |
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What they said ^
I have read senescence is more likely to occur if the substrate or medium that you are transferring your isolate to is invariable e.g. agar to agar to agar transfers ect.
semi-off topic, has anyone capture the horse manure draining water from their pasteurization projects and used it for the water in their agar mix to reduce the odds of senescence occurring?
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champinhom
Lord Justhappensness


Registered: 03/06/09
Posts: 987
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Re: senescence. [Re: Rictus]
#22036006 - 08/03/15 12:03 AM (8 years, 5 months ago) |
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Quote:
matsc said: Senescence is an odd thing, and very very difficult to pin down with any specificity. Even if you had two batches cloned from the same fruit, treated identically, they may fade at differing rates.
Eventually, over time, genes that become "useless" to the organism will become lost. Sometimes they're mutated and there is no longer a selective pressure to keep them around. Some times recombination will scramble a locus or two. Basically you've taken a wild organism and planted it in a very artificial environment with a very different set of conditions that are "optimal". As the organism adapts to this new local, it may well lose the traits that made you desire it in the first place.
I run into this pretty often in lab, studying plant pathology. We take a wild plant pathogen fungus, and after several serial platings, it loses its pathogenicity. Basically because rather than having to optimize itself for living in/on a plant and deriving nutrients from there, its now growing on agar plates with a strange mix of salts and supplements. Why keep the genes for plant life if they are no longer useful?
All of this is new to me. How wonderful it is the way life operates. It is intelligent, intelligent on every level and in all its modalities.
-------------------- My father used to say: I don't care what else you do in life, just don't be an asshole. People, forgive me when I forget what my daddy said. Cut back the proliferating list of people whose opinions can hurt you. Unless they have done or want to do you some good, their views are just not worth tracking. Saul Bellow “People are just cannibals unless they leave each other alone.” Doris Lessing Those whom the gods would save, they dower with compassion. Mr. P. Silocybin
Edited by champinhom (08/03/15 12:04 AM)
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Rictus
Stranger

Registered: 06/08/15
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matsc is talking less about senescence and more about adaptation it seems.
Here is a definition from dictionary.com 1.growing old; aging. 2.Cell Biology. (of a cell) no longer capable of dividing but still alive and metabolically active. Anything that does not follow these guidelines IMO is not senescence.
Has anyone capture the horse manure water from their pasteurization projects and used it for the water in their agar mix to reduce the odds of senescence occurring?
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matsc
Stranger



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Re: senescence. [Re: Rictus]
#22050289 - 08/05/15 09:12 PM (8 years, 5 months ago) |
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The definition of senescence gets a little fuzzy when dealing with microorganisms. Since you are looking at things at cell-scale resolution, you don't really track the age of any single cell, since each division technically results in two new cells...
However, you are partially correct. True cellular senescence is more related to things like telomere shortening and reactive oxygen species build up. However, at least on this forum, 90% of the time what people are talking about is the deterioration of behavior over time (IE a culture failing to fruit after serial subculturing). So, points for pointing out the vocabulary!
https://en.wikipedia.org/wiki/Senescence#Cellular_senescence
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Kizzle
Misanthrope


Registered: 08/30/11
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Re: senescence. [Re: matsc]
#22051155 - 08/06/15 12:00 AM (8 years, 5 months ago) |
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In a nut shell:
The unique coenocytic anatomy of the mycelia of the filamentous fungi and the formation of anastomoses between hyphae from different mycelia enable the intracellular accumulation and infectious transmission of plasmids and mutant mitochondrial DNAs (mtDNAs) that cause senescence. For reasons that are not fully apparent, mitochondria that are rendered dysfunctional by so-called "suppressive" mtDNA mutations proliferate rapidly in growing cells and gradually displace organelles that contain wild-type mtDNA molecules and are functional. The consequence of this process is senescence and death if the suppressive mtDNA contains a lethal mutation.
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matsc
Stranger



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Re: senescence. [Re: Kizzle]
#22051699 - 08/06/15 02:57 AM (8 years, 5 months ago) |
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I hadn't heard the mutant mitochondria theory before, very interesting. Wonder if its a bigger issue in mixed cultures (IE multispore) or monocultures. Time to dig up some literature!
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champinhom
Lord Justhappensness


Registered: 03/06/09
Posts: 987
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So, nature doesn't favor clones. She tolerates them for a time and then tears them down.
-------------------- My father used to say: I don't care what else you do in life, just don't be an asshole. People, forgive me when I forget what my daddy said. Cut back the proliferating list of people whose opinions can hurt you. Unless they have done or want to do you some good, their views are just not worth tracking. Saul Bellow “People are just cannibals unless they leave each other alone.” Doris Lessing Those whom the gods would save, they dower with compassion. Mr. P. Silocybin
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