[Rox]

Originally Posted by Only Ornamental

Interesting subject!
Not sure how good that strategy will pay off with cannabis, though. There might be simple protocols which 'accidentally' work on cannabis too but what do you do with a doubled haploid then? It will most likely be a fragile, sick, weak, crippled runt whose only sense in life is being a homozygous carrier of a valuable and/or new mutation which will only come into play once outcrossed. To me right now (I admit, it's been a long day for me) it seems less trouble (and certainly more fun) to create a doubled haploid just because you can than all the crossing with other doubled haploids needed to find the real goal, a 'perfect' F1. Without genetic markers, the value of a DH especially in outcrossing species seems rather low to me.

I was reading into that subject a while back and there's a bunch of feasible strategies for certain crops. Most often, it's a freak of nature or a coincidence which creates and/or rescues the haploids of a given plant species (for example wide crossing in barley or tobacco: doesn't work so far with cannabis x hops, or does it?). Colchicine and IIRC also caffeine are used in the second step where you double the chromosomes. You should probably focus on gyno- and especially androgenesis . If I can re-find those papers again, I'll let you know.

A freak like a Polyembryonic seed where one will be a normal offspring of mother and father and the other is an exact copy of the mother?


https://sensiseeds.com/en/blog/top-1...bis-mutations/

[Only Ornamental]

No, not like that... (besides, there won't ever be an exact copy of the mother but that famous doubled haploid, a 'perfect and instantaneously obtained 100% inbred' plant).
It's rather a funny turn in evolution/biology which makes it possible to easily obtain doubled haploids with certain plants; it's that exception to the rule which states that there's not a chance of a snowball in hell for such a DH to happen 'just like that'. Our world is still a place of awe and wonder (at least sometime)!

[Fuel]

idk if it can help in a way or another, 13 years old tests


But i'm sincerely skeptic about your theorical shortcut.
I've somes difficulties to translate "true breeding", can someone explain me it in this context ?

[Only Ornamental]

Dunno what your pic should show??? It's a plant and... ???

Suppose you first need to understand what a DH is:
A doubled haploid is a really and truly 100% inbred plant wherein both corresponding chromosomes of every chromosome pair are absolutely identical. Normal inbreeding like it's done by home growers and hobby gardeners never gives that (a dozen successive selfings might get close to it but still, not a full 100%); the chromosomes from father and mother (even if they're the same plant) are always slightly different. There are a few strategies that work on certain crop species which immediately i.e. within one generation lead to full inbreeding. That's the shortcut and it's only theoretical with regard to cannabis.
A DH is true breeding because it's offspring is 100% identical with the parental line, it's homozygous on every single gene, and hence the offspring inherits all the visible and invisible traits from it's parental generation. Standard 'inbred strains' like those advertised on seedbank HPs are at best true breeding regarding a handful of traits.

Hope that clears things up! Else, wikipedia is your friend .

[Illuminate]

Serbed

[Fuel]

The term "true breeding" simply don't exist in my native language, word for word it mean nothing for me. That's why. It was a good opportunity to decypher it one time for good, i don't have seen a single entry in wikipedia on this exact term. I thinked initially that "true breeding" mean just a good work. But this subject changed this point of view. Thanks for the explanation.

I'm losted in one point. If you consider that "true breeding" equal genetical clones with DH specimens, i don't understand the use of this term also for an (good) inbred line wich is not a genetical clones group.

[Tonygreen]

Supreme f1s would be the obvious use.

[Only Ornamental]

I'd say predictable F1s where every single plant is exactly the same. Very important for example in cereal crops: every ear the same hight .
It's rather laborious though without having genetic markers which help to decide DH to keep and which to trash cause most DHs especially in outbreeding species look like crappy runts and only show their value in F1 crosses.

[Elmer Bud]

Originally Posted by Fuel

The term "true breeding" simply don't exist in my native language, word for word it mean nothing for me. That's why. It was a good opportunity to decypher it one time for good, i don't have seen a single entry in wikipedia on this exact term. I thinked initially that "true breeding" mean just a good work. But this subject changed this point of view. Thanks for the explanation.

I'm losted in one point. If you consider that "true breeding" equal genetical clones with DH specimens, i don't understand the use of this term also for an (good) inbred line wich is not a genetical clones group.

G `day F

I take it to mean breads true for type .
Chemo type and pheno type . Doesn`t segregate successive in f ?

@ TG
You don`t think Rob and Sam might have already investigated this theory and found a dead end ?
I`d ask Sam re before investing .

Doubled Haploids: A simple method to improve efficiency of maize breeding

Thanks for sharin

EB .

[earthwyrms]

what do you think about recycling soil (no runoff, closed container) with realgar / orpiment (barely soluble arsenic sulfides) as soil amendments? the effect, with other treatments could possibly induce mutation. maybe adding some bismuth (which is also a pnictogen like N P As and Sb) could effect it. i looked at a google image search of "arsenic india topographical map" or something and it makes me wonder if that effected some changes in the forms of cannabis. i don't know if the plants would be so smokeable, unless solvent extracted, but could be composted with the soil. when i look at plant hormones, like ytokinens and auxins, i wonder what arsenic modidifications to those moleules would do to plant DNA or RNA (in plants, right?) transcription. i also wonder about the saliylate in the bismuth saliylate. i forgot to mention pepto bismol is a bismuth source, with bismuth salicylate. and salycilates, like aspirin i think stimulate plants to disease or like a hormone or psuedo hormone effect or something.

i dunno, looseknit concepts, but maybe something. like maybe it could mean something, even with modification, in situ / soil medium of the colchicine, caffiene, oryzalin (if this sort of thing is done in situ).

also, as i don't know much of anything about this, is this similar or not to apple trees, where apple trees have so much diversity, they have to be grafted, beause growing them from seed gives too many undesirable traits?