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fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
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Re: Strain Thread-Strain Discussion Here Only Please [Re: newera]
#18263737 - 05/14/13 01:10 PM (10 years, 8 months ago) |
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Quote:
newera said: i got some spores from an old hippie who said he had been growing them for years and taking his own prints, after a sad performance he tells me that he might be over using his variety, meaning growing/printing/growing/printing/growing/printing and tells me that over time, the result of this can be weakened genetics and it might be time for a fresh start. is there any truth to this or am i hanging out with a man whos done too much acid?
Certainly there's truth to this. Whenever you grow in controlled conditions you are breeding a weakened strain that will only thrive in these conditions. They will gradually lose their natural ability to cope with variable conditions.
This problem happens with yeast fermentations all the time. Large scale ethanol production especially suffers from this problem. It even happens to beer and wine brewers...
Quote:
Degeneration of Yeast Yeast degeneration refers to the gradual deterioration in performance of the brewing yeast. Yeast degeneration has a harmful effect on the course of brewing fermentations. It is characterized by some of the following symptoms: sluggish fermentations, premature cessation of fermentation (resulting in high residual fermentable levels in beer), gradual lengthening of fermentation times, and poor foam or yeast head formation (50). Some brewers have noticed that the flavor of beer becomes increasingly "dry" as a result of yeast degeneration.
There seems to be a systemic misconception here about basic genetics. People have the idea that the original strain is somehow reconstituted every time you go from spores.
Our strains are highly inbred, since the nature of mushrooms is to inbreed through sibling crosses the majority of the time. But this doesn't mean the parental genetics are magically reconstituted every time you go from spores.
Since they're so inbred they're largely homozygous, so with very little starting variation you end up with offspring very similar to their parents.
In any case, when you have useless genes due to the selection conditions, they are gradually lost due to mutation and recombination. A gene for poo metabolism will eventually be lost if you grow only on BRF long enough. A gene for cold tolerance will be lost if you only grow at 70-72F for long enough. What you end up with is a weak strain that is barely capable of surviving in optimal conditions.
When you eliminate selective pressure almost entirely you end up with weak genetics. Grow a bacteria in sterile sugar-rich media long enough and it will lose all ability to deal with anything. Usually this will even get to the point that they don't even grow well in the sugar media. Since every offspring survives no matter how unfit, you end up with garbage genetics.
A little basic genetics knowledge goes a long way to dispelling the myths that circulate here as fact.
-FF
-------------------- It drinks the alcohol and abstains from the weed or else it gets the hose again. -Chemy The difference between the substances doesn't matter. This is a war on consciousness, on our right to the very essence of what we are. With no control over that, we have no need to speak of freedom or a free society. -fireseed "If we are going to have a war on marijuana, the least we can do is pull the sick and the dying off the battlefield." -Neal Levine (MPP) I find the whole "my drug should be legal but yours should be illegal" mindset disgusting and hypocritical. It's what George Bush and company do when they drink a cocktail and debate the best way to imprison marijuana users. -Diploid
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FrankHorrigan
The Inquisition



Registered: 01/04/11
Posts: 10,573
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Re: Strain Thread-Strain Discussion Here Only Please [Re: fastfred]
#18263758 - 05/14/13 01:17 PM (10 years, 8 months ago) |
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I understand what you are saying FF but what can be done about it?
Most people have no idea how many indoor generations the prints are the product of and there is really no way to tell.
Short of getting a wild cube specimen, printing it and cleaning it up on agar, I'm not sure there is a way to tell how much "better" or "worse" a new print will be by those standards 
So that is why I said that starting from spores is generally considered a fresh start.
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Baby_Hitler
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Re: Strain Thread-Strain Discussion Here Only Please [Re: fastfred]
#18263774 - 05/14/13 01:19 PM (10 years, 8 months ago) |
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If this is true, then why haven't all the popular strains that have been in circulation for 40+ years since they were originally taken from the wild degenerated to the point of being useless?
-------------------- Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ Ƹ̵̡Ӝ̵̨̄Ʒ (•_•) <) )~ ANTIFA / \ \(•_•) ( (> SUPER / \ (•_•) <) )> SOLDIERS / \
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Sillyputty67

Registered: 10/06/12
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Re: Strain Thread-Strain Discussion Here Only Please [Re: Baby_Hitler]
#18263791 - 05/14/13 01:22 PM (10 years, 8 months ago) |
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Because theory and practice often yield different results. NTM this genetic evolution/degradation that FF is talking about IME takes place over thousands of years.
Edited by Sillyputty67 (05/14/13 01:23 PM)
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Rose
Devil's Advocate



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Re: Strain Thread-Strain Discussion Here Only Please [Re: Baby_Hitler]
#18263877 - 05/14/13 01:43 PM (10 years, 8 months ago) |
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Quote:
Baby_Hitler said: If this is true, then why haven't all the popular strains that have been in circulation for 40+ years since they were originally taken from the wild degenerated to the point of being useless?
Tampanensis, for one, suffered from inbreeding.
-------------------- Fiddlesticks.
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fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
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Re: Strain Thread-Strain Discussion Here Only Please [Re: FrankHorrigan]
#18263884 - 05/14/13 01:46 PM (10 years, 8 months ago) |
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You can vary your media and conditions occasionally for a generation or two to maintain the desired hardiness, or outcross with other strains.
Mushrooms are naturally so highly inbred that it's hard to get any real variation out of a given strain. There's really no easy answer, but constant conditions allow degeneration of the strain. Once it's lost it's gone forever unless you outcross to another strain, which will probably suffer from the same problems to some extent.
Going back to wild type strains occasionally is one solution. But there's probably not much genetics worth salvaging.
Maintaining some sort of variation in the conditions helps. You could also back-cross with younger genetics, or just start over. It's very easy to keep some original spores or cultures and go back to them occasionally.
If you don't have a specific structured breeding program then you should just realize that your constant conditions will eventually cause the strain to degenerate. Any time you don't have an actual breeding program you should occasionally go back to the source. The thing to realise is that if you're not improving the genetics then they are slowly degenerating.
Alcohol and milk are good examples of this in humans. Selective pressure caused alcohol metabolism to evolve and lactose tolerance to extend past childhood. If that selective pressure was removed you'd end up with a bunch of lactose intolerant alcoholics. If you fed babies nothing but formula you'd probably eventually end up with a complete and total lack of lactase production.
There's always a slight selective pressure against unneeded enzymes, so it's important to vary conditions through the range of what you want your organisms to tolerate. There's no reason an alcoholic prone lactose intolerant individual can't do just as well in our society as long as they avoid milk and alcohol. Not to dis any of these individuals, but I wouldn't consider them the genetically fittest individuals in an evolutionary sense.
-FF
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fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
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Re: Strain Thread-Strain Discussion Here Only Please [Re: Baby_Hitler]
#18264022 - 05/14/13 02:22 PM (10 years, 8 months ago) |
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Quote:
Baby_Hitler said: If this is true, then why haven't all the popular strains that have been in circulation for 40+ years since they were originally taken from the wild degenerated to the point of being useless?
I would imagine that the "breeders" go back to earlier generations if/when they run into problems. If a generation were destroyed by contams or performed so poorly as to present a problem they would likely go back to earlier stocks. That's a pretty effective form of selection.
One would hope that unless a breeder saw improvement then they would try to preserve the greater variation of earlier stocks.
Quote:
Because theory and practice often yield different results. NTM this genetic evolution/degradation that FF is talking about IME takes place over thousands of years.
Evolution takes place between generations. There's no rule that it takes any given length of time.
Variation x selective pressure = rate of evolution.
Look at humans and our propensity for genocide. If we applied extreme selective pressure by wiping out asians/whites/blacks/etc. we would have caused an extreme form of evolution in one generation.
The same thing happened with peppered moths in England...
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The evolution of the peppered moth over the last two hundred years has been studied in detail. Originally, the vast majority of peppered moths had light colouration, which effectively camouflaged them against the light-coloured trees and lichens which they rested upon. However, because of widespread pollution during the Industrial Revolution in England, many of the lichens died out, and the trees that peppered moths rested on became blackened by soot, causing most of the light-coloured moths, or typica, to die off from predation. At the same time, the dark-coloured, or melanic, moths, carbonaria, flourished because of their ability to hide on the darkened trees
We spewed out a bunch of soot and within a handful of generations moths evolved from spotted to black.
This is how evolution works. It's not a geologic time scale, you can witness it with your own eyes, well within your lifespan. The geologic theory of evolution is dead. You can look at any species and see very slow evolution, frequently punctuated by rapid evolution.
Frequently a single base pair will change through mutation or natural recombination and cause a phenotypic variation, combined with selective pressure, and you'll get a major shift within a generation or two.
It all depends a lot on random factors, but it breaks down to variation x selective pressure. When you have a large number of individuals competing for the same resources you have a pretty high selective pressure. One genotype/phenotype quickly dominates, and then the selective pressure is quickly removed.
IMHO with inbred species like mushrooms you end up with the slight advantage of not possessing an enzyme quickly dominating the gene pool. Then the lack of selective pressure allows even the weakest individuals an equal chance of success and leads to degeneration.
-FF
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Sillyputty67

Registered: 10/06/12
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Re: Strain Thread-Strain Discussion Here Only Please [Re: fastfred]
#18264056 - 05/14/13 02:31 PM (10 years, 8 months ago) |
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Good Stuff FF!
-------------------- 1) Everything I ever posted or say is a lie.
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wildernessjunkie
Reshitivest



Registered: 06/13/10
Posts: 8,118
Loc: HTTP 404 Not Found
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Re: Strain Thread-Strain Discussion Here Only Please [Re: Sillyputty67]
#18264525 - 05/14/13 04:24 PM (10 years, 8 months ago) |
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Anyone know of a good write up for a mycological breeding program?
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Rose
Devil's Advocate



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Re: Strain Thread-Strain Discussion Here Only Please [Re: wildernessjunkie]
#18265860 - 05/14/13 09:15 PM (10 years, 8 months ago) |
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Yes.
The search engine.
-------------------- Fiddlesticks.
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FrankHorrigan
The Inquisition



Registered: 01/04/11
Posts: 10,573
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Re: Strain Thread-Strain Discussion Here Only Please [Re: Rose]
#18266180 - 05/14/13 10:06 PM (10 years, 8 months ago) |
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I'm so confused.
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k00laid
NEMO


Registered: 05/03/10
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Re: Strain Thread-Strain Discussion Here Only Please [Re: fastfred]
#18266195 - 05/14/13 10:10 PM (10 years, 8 months ago) |
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Quote:
fastfred said: Mushrooms are naturally so highly inbred that it's hard to get any real variation out of a given strain. -FF
i dont know about this.
my experience has been the exact opposite.
i've had spores from the same print (if thats what you mean by strain) that have given me WILDLY different results.
-------------------- AMU - AMU Q & A - MyVideo Teks!
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InTheBiggun
The Milk-Man



Registered: 06/01/09
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Re: Strain Thread-Strain Discussion Here Only Please [Re: FrankHorrigan]
#18266231 - 05/14/13 10:17 PM (10 years, 8 months ago) |
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If a person is making a thread in cultivation, is it okay to mention what "variety" or name of the Cubensis you are growing, say like APE, Redboy, A+ albino etc?
I wanted to make a thread but didn't want to get in trouble for breaking the rule of talking about strains...
Like say PE, can you make a thread and describe what your growing as PE?
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FrankHorrigan
The Inquisition



Registered: 01/04/11
Posts: 10,573
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Re: Strain Thread-Strain Discussion Here Only Please [Re: InTheBiggun]
#18266234 - 05/14/13 10:19 PM (10 years, 8 months ago) |
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Quote:
InTheBiggun said: If a person is making a thread in cultivation, is it okay to mention what "variety" or name of the Cubensis you are growing, say like APE, Redboy, A+ albino etc?
I wanted to make a thread but didn't want to get in trouble for breaking the rule of talking about strains...
Like say PE, can you make a thread and describe what your growing as PE?
Yep!
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Rose
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Re: Strain Thread-Strain Discussion Here Only Please [Re: FrankHorrigan]
#18266251 - 05/14/13 10:23 PM (10 years, 8 months ago) |
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Neither opinion is science.
Inbreeding IMO can harm natural selection.
But not always. It can also make special things happen... Like PE.
-------------------- Fiddlesticks.
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Javadog
Continuing along



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Posts: 7,385
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Re: Strain Thread-Strain Discussion Here Only Please [Re: wildernessjunkie]
#18266498 - 05/14/13 11:17 PM (10 years, 8 months ago) |
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Quote:
wildernessjunkie said: Anyone know of a good write up for a mycological breeding program?
You deserved some sort of answer WJ, you did not just fall off the turnip truck. :0)
I will throw this out as my best guess.
Take care,
JD
P.S. This looks even closer, but wow is it expensive!
-------------------- Boyd Rice told my brother that life is a corny pack of freesakes Myco-tek.org
Edited by Javadog (05/14/13 11:43 PM)
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wildernessjunkie
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Re: Strain Thread-Strain Discussion Here Only Please [Re: Rose]
#18267056 - 05/15/13 01:59 AM (10 years, 8 months ago) |
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Thanks JD.
Both of those are pretty spendy. Maybe soon though.
For anyone else curious about a better answer, I found these
http://www.shroomery.org/forums/showflat.php/Number/5194890/fpart/1/vc/1
http://www.shroomery.org/forums/showflat.php?Cat=0&Number=5713255&page=0&vc=1
Both of those are write ups by Workman regarding breeding.
This one I haven't read yet, its pretty long, but seems to fit the bill.
http://www.shroomery.org/forums/showflat.php/Number/2659086#2659086
From what I found, it seems like any serious and documented effort regarding breeding on the Shroomery happened 7-9 years ago. Maybe there's more recent documentation, but I didn't see any.
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Rose
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Re: Strain Thread-Strain Discussion Here Only Please [Re: wildernessjunkie]
#18267171 - 05/15/13 02:50 AM (10 years, 8 months ago) |
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Workman? Who is that?
-------------------- Fiddlesticks.
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fungitarian
oliver hart


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Re: Strain Thread-Strain Discussion Here Only Please [Re: Rose]
#18267194 - 05/15/13 03:00 AM (10 years, 8 months ago) |
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-------------------- have a look at my grow. "genius by day, junkie by night"
Edited by fungitarian (05/15/13 03:00 AM)
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wildernessjunkie
Reshitivest



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Re: Strain Thread-Strain Discussion Here Only Please [Re: Rose]
#18267219 - 05/15/13 03:10 AM (10 years, 8 months ago) |
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Quote:
Cervantes said: Workman? Who is that?
I bet he can be found with the search engine.
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