diminishing potency

[swayambunath]

Hi, this is possibly a stupid "newbie" question, but I have often read that potent drug strains will revert (for want of a better word) to non-potent forms when grown for several generations in shitty climates like mine (British Isles, 52n).
Is there any truth to this? It sounds like "received wisdom" to me, as presumably once a drug strain has been stabilised as such, there is no reason I can see why it would somehow quickly mutate or "devolve" to an undesirable form. It sounds like nonsense.
However, I've heard it enough times to be curious if anyone has first hand experience of this.
Thanks,
Swayambhu

 

[swayambunath]

After seeing my post, I would like to say that the italicized, underlined and emboldened "first hand" wasn't meant to look quite as fascist as it does, but I can't edit it.
Anyway, your thoughts are appreciated!

 

[Sinkyone]

Over time strains that are inbred will suffer from what is called 'inbreeding depression' which causes a loss of vigor, yield and potency and an increased change of recessive deleterious mutation manifesting. It's not so much that they mutate or devolve it's more due to the fact the fitness of a given population declines when related individuals reproduce.

 

[Sat X RB]

Now this is an interesting question for me because I grew aussieweed (sativa) for 12 -14 grows (can't recall exactly ... don't keep records) fertilised each season with the best looking female that sex-altered and then carefully selected seedlings for the next grow. so no 'new blood', right?

it seems to me and my friends that this variety became more potent as the years went by. would be growing it now as my preferred strain but lost my seeds thru heat. (the strain ended up greater than 80% female germination.)

so that's one first hand experience over a given period of time.

but I have great respect for a well known australian breeder who says that plants acclimatise to their environment and will not increase in potency unless they are introduced to an area of increased sunlight hours.

so that's a trustworthy second hand opinion which tends to support the proposal within yr post.

the breeder says my strain continued to improve due to the number of sunlight hours available to me ... but my strain would only continue to improve to the extent local sunlight hours would allow ... and then their potency would plateau ...

what do y'all make of that?

cheers from Oz!

 

[Kcar]

Why not make a mother, and just use clones off of her? Not sure if I buy into the whole
'Strain degradation' through whatever means. Phenotypes will exhibit different traits
depending on environment, but I don't get how hours of daylight would play a part in potency.
Yield, certainly. But potency is more of a genetic trait, with environment playing it's part.

 

[swayambunath]

Kcar, I'm with you on this, but I have heard it enough times to make me wonder.

Sat x RB; I have heard/read that resin production has been linked, hypothetically, to sunlight exposure. By which I mean these plants started producing resin to protect themselves from UV or whatever. This also doesn't ring true, and even if it did, if we can presume that yield and potency are the same thing in respect to being environmentally predicated, this would not be any indication of genetic selection. If you see what I mean?

Sinkyone; I understand what you mean. I am beginning to believe that this theory must, necessarily, be a load of bunk, if we can make the basic and, to me self-evident assumption that potency is, or rather potential potency is genetically based.

However, there might still be something to it, as life forms are complex and can be temperamental?

 

[spiralofeyes]

See,I'm on the same level as you,Swayambunath,but the opposite end of the spectrum as it were...i.e, I have no first hand experience but the theory makes perfect sense to me.

I'll try to explain why:
Phenotypical expression= 50% genetics + 50% environment,right? Basic fact of biology. A fact that has only been strengthened by the discovery/formulation of epi-genetics(i.e the mechanisms through which the expression of an organisms genome can change rapidly to cope with changing environmental parameters during the individual's lifespan). The real trip is that these patterns of expression can be inherited. A good example in human biology is the effects reduced nutrient intake had on the DNA of people who were in the womb during the Dutch hunger winter of 44-45.


So environment not only ''selects'' for certain traits through the generations,it actually leads to genes being turned on/off within a given generation.
It is my contention then,that if we leave any drug cultivar to be shaped by it's environment at a northern latitude for long enough,what do we end up with? Ruderalis.
Which is the species' answer to the challenges posed by the northern european climate. The emphasis here is on leaving selection to the environment.

It's not that a cultivar bred at northern latitudes will become hemp,no matter what. You,as the grower/breeder just have to be veeeeeeery careful about keeping drug traits in the mix as you go down the generations .

Hell,even indoors you gotta be careful of hemp-type phenos creeping in. A bunch of breeders have warned against using only the biggest, earliest individuals(a selection criteria that makes sense in short,cold,wet summers),because selecting for hemp traits will give you....HEMP.

 

[swayambunath]

Thank you for your reply, spiralofeyes, and first of all, could you point me in the direction of more information on the Dutch 44-45 generation thing, I'd not heard of it before.

My reposte to your excellent points is to question why a drug strain would "turn off" it's drug making capacities? Why would this not happen in the first generation of being grown in an unfavourable climate? This might sound stupid, but people with dark skin do not become light-skinned over generations. Sure, they will go a lot darker when they go on holiday, but I think that in order for something to be really "turned off", let alone selected out, it needs to be a hindrance to life and reproduction.
Also, I am not saying that you believe this, but I think there is often an assumption that the hemp type, or at least non-psychoactive plant is the "normal" type, and that the drug type is more highly selected for. In my experience of wild plants on the Indian subcontinent, that is not true.

 

[spiralofeyes]

Gladly,bro: this is an easy to read run-down of the findings of the study. More in depth stuff should be sited here too. http://www.dutchfamine.nl/index_files/results.htm


My simple answer to psychoactivity in particular would be that cannabinoids are complex molecules and therefore biologically ''expensive'' to produce. In a pressed environment,without human selection to maintain the trait it'll be one of the first things to go,IMO. I don't really know though. That is just what fits in with my worldview and general knowledge.

Well...cannabis is a slippery one for sure. I don't think or current taxonomy can really account for all the grey areas here...
But if we take it for granted that all the different cultivars/varieties have a common ancestor,a proto-cannabis if you will,being fiberous,tall and strong would help this plant far more then chemicals that get bald,pink monkies to like it. If hemp already was psychoactive before we started growing it and we just increased it. Or that it actually evolved this trait through its interaction/symbiosis with us...well that's way outside of my competence.
Fringe-biological theory like Sheldrake's whole morphic resonance-deal cold be the answer...

 

[swayambunath]

Thanks for the link, and for your reply.
As you say, cannabis seems to be a slippery one.
It seems people are not sure why they produce resin in the first place (I may be wrong).
In my internet "research" I have found many posts in online forums that state, pat, that drug cultivars will revert to hemp if bred in cold/dark environments.
I don't want it to be true, obviously, but it also has the ring of stoner "wisdom" based in a garbled article in "High Times", from the 1980's.
I suppose it comes down to the hand of man, in the end.

 

[Ajunta Pall]

It's not that slippery, it's simple genetics really. High potency is a trait like any other, color, height, whatever... Cross two parents with similar traits the resulting offspring will have said trait. Okay, the majority will express it, that is. As long as you don't introduce any inferior genetics into the gene pool, you should be able to isolate the traits you want in your plants.

Other non genetic factors tend to be human in their cause. Harvesting too early or growing plants that won't fully finish at your latitude, all it takes is for someone to keep repeating the same mistakes over and over. Not that uncommon really.

But no it won't lose potency just by being bred over and over on its own. Assuming its acclimated to its environment.

 

[Sat X RB]

now, y'all asked for first hand experience ... and you got mine.

all else here is theory.

I think that a strain will NOT lose its vigour thru inbreeding. the genes will always be there. otherwise strain hunters would have nothing to do.

cheers!

 

[Wendull C.]

I run a very old clone of og. I thought that it was having a problem with genetic drift. Though it is yieilding better than ever if it is stressed in any way or left to flower to long it will pop a few beans. Never in the first ten years could I even find a seed. Maybe the more scientific minded could tell me it's not drift?
One more thing about the same strain, when the cut was given I gave it to a trusted friend who doesn't grow for anyone but his own medical needs. Now after a decade his cut has gotten more of a diesel smell while mine has a sweet hashy finish for an og and we both use the same techniques and nutes.
Neither cut is as skunky as when we got it.
That is the only experience I have with genetic drift.
Would have kept quiet but the knowledge in this forum is amazing and I'm hoping one of the many biologists and botanists could shed more light on this subject.
I think this is off topic, if so I sincerely apologize for not reading the thread close enough. Thank you guys for your knowledge and opinions.

 

[Nunsacred]

Hi, this is possibly a stupid "newbie" question, but I have often read that potent drug strains will revert (for want of a better word) to non-potent forms when grown for several generations in shitty climates like mine (British Isles, 52n).
Is there any truth to this? It sounds like "received wisdom" to me, as presumably once a drug strain has been stabilised as such, there is no reason I can see why it would somehow quickly mutate or "devolve" to an undesirable form. It sounds like nonsense.

There's some truth to it because there's a tendency for this to happen.
However it doesn't have to be like that.

I almost agree entirely(90%) with the answer from spiralofeyes.
Particularly the warning about using only biggest fastest plants for parentals.

A Nepalese strain has been grown in far North Europe for over 30 generations, look up Dyr or Tanska, that Nepal is still potent and good.
I don't think a grower has to be "veeeeeeery careful" to maintain potency I think it's simply a matter of including the slower growing, more potent ones in the parental stock.

Most people are careless and don't do this.

Epigenetic drift does affect gene expression but there's no easy rules for that. Each hybrid will be different in the way it's affected. I think there are random elements to it, which is why Wendull sees differences to his mate in the same clone line.
Apparently tissue culture can help but clearly it's easier to just breed the line and use what works for your set up.

 

[swayambunath]

Thanks to all for the excellent answers, they make a lot of sense!

 

[Wendull C.]

Thank you Nunsacred. They won't let me rep you.

 

[Nunsacred]

I've probably got a problem with at least one member of staff here by now.