You can see the difference on some things, but not every gene has a visible expression. The leaves are incredibly obvious, the bud structure slightly less so, and cannabinoid/terpene profiles are pretty damn tough to tell without at least harvesting, curing and smoking - though that only gives you a rough idea, and doesn’t tell you the actual chemical content, just how your particular body chemistry reacts to it. I think you’re oversimplifying things here. You aren’t just going to have “ABC leaners” and “indica/sativa leaners,” you’re going to have a very wide range of expressions from ABC to your mother plant, most of them hybrids that are tough to judge.
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Yep that first f1 you’ll have plants that look like the dad but smoke like the mom and vice versa. Likely need to run at least a few packs to find one that has most of what you want in one plant.
Really good answer 
so many recombinant possibilities in the F1’s, oversimplifying is the perfect word. Not to say this method won’t work, but it’s going to be more difficult than anticipated. Likely very large hunts, and if you make the wrong crosses, you’re breeding into a dead end.
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For real what @Cormoran said.
No matter what phenos you chose, the original genetics are still inside.
The the potential to get plants that you don’t like is great… especially when you breed the plants who share those genetics together.
You will end up back where you started taking that route.
There is a better way.
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Are you describing cubing?
Thats a long disproved method
Was thinking about the idea of using a male as the original bx parent. Kind of a reverse back cross. But I don’t see why that would change the idea that you’re still isolating genes.
It would make things a lot easier in my opinion.
Instead of testing new males each bx you have your 1 original tested stud.
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What do you mean by disproven?
But no that is an explanation of backcrossing.
Edit: so apparently it’s the same thing.
For the past few years, i’ve been repeatedly backcrossing an abc to Pine Tar Kush with the hope of making a strain that smokes and tastes like PTK but has abc leaves and growth structure. I’m finishing up the second generation, which i hope to grow outside this summer and am starting the 3rd generation(2nd backcross). I suspect I understand what you hope to accomplish, but i question whether the abc makes an ideal male plant for your needs. You won’t get the abc leaf in the F1 generation, so the abc leaf becomes irrelevant. If you breed the F1 back to the mother plant, you won’t get any abc leaves in the resulting generation either. Without having more details, i would recommend using a male donor that has attributes you would like to pass on, even though you will be breeding away from the male.
As a side note, @Tonygreen did a 5 generation backcross with GG4 and sour bubble before making his RIL. He’s been very transparent with the process and his writings on the subject make for some great educational reading.
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Yes, for the most part. Cubing is repeating the backcross over and over. Chimera has commented that it doesn’t actually work that way though.
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Yeah it’s a very intricate process.
You can make a line that strongly resembles the original mom if done correctly along with some luck.
Could even find twins of the original mom.
Working with a stable mom in the first place helps a lot.
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I’d love to hear his explanation. Do you have a link?
I’m not sure how using the exact genes you want multiple times(original mom) would not atleast help isolate genes you want.
It’s not an exact thing obviously. But it’s a good method atleast. And has a lot of evidence that it works decently. In some cases very well. It all depends on the selections.
But hey 
I’m no scientist
I do think taking a specific mom to s2+ would be better. For me personally. Makes a lot more sense. But if you want males… obviously not an option.
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This all started with a question, what’s the easiest way to BX? Then it was presented as what if OP makes a cross and eliminates all of the Y chromosomes through a backcross process? The answer was never needed. The OP already knew it was a good idea… he just wanted acceptance and agreement.
OP clearly has the idea of how to backcross down, so the title is invalid. OP also seems to know exactly how the process will go if he crosses a Aussie Bastard Cannabis male with some random female. I suppose the idea within the OP’s head is that using ABC will be some sort of short cut to a final product. That kind of thinking is wrong unfortunately.
I’d like to add… you would be the first person I have ever heard of, ever, that has successfully eliminated Y chromosomes in Cannabis through backcross selective breeding, ending with the final result of something that is like making an S1 out of regular seeds. Nobody has done that yet. Ever. Not to any degree of success at least. If you pull it off and everyone agrees you pulled it off, you will be admired and revered by at least 12 people who care about what you did. Good luck brother, you will need it! 
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Probably in this 5 hour podcast, it was a brief, “you’ll never get there” comment. Sorry, I know it’s pretty long.
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Oh lord 
!
I appreciate that.
Well I’m guessing he means you’ll never get to the point of the seeds all being an exact replica of the original mom.
But we all understand that already.
Chimera is a bit of a high horse individual sometimes lol.
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The issue would come in if the traits you want only show themselves by Dominance/Co-Dominance. Repeated Backcrossing is going to double up on homozygous (AA or aa) traits, so if it’s a heterozygous (Aa or aA) trait, simply backcrossing is never going to make it show up. You’d have to F2 the bx line to hope to see it.
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Yeah I’d have to agree with you 
.
For heterozygous traits it might even be better to just consecutively breed the progeny for those traits. Like f2, f3, f4 etc …
Or like I said… selfing a few times. I wouldn’t feel comfortable taking this too far though.
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Cubing…a myth.
Here’s breeder chimera’s take on the subject:
"you’ve just discovered the biggest myth (IMNSHO) of marijuana breeding- it is a mistake that almost EVERYONE makes (including many of the most respected breeders!).
Backcrossing will not stabilize a strain at all- it is a technique that SHOULD be used to reinforce or stabilize a particular trait, but not all of them.
For e.g.- G13 is a clone, which I would bet my life on is not true breeding for every, or even most traits- this means that it is heterozygous for these traits- it has two alleles (different versions of a gene). No matter how many times you backcross to it, it will always donate either of the two alleles to the offspring. This problem can be compounded by the fact that the original male used in the cross (in this case hashplant) may have donated a third allele to the pool- kinda makes things even more difficult!
So what does backcrossing do?
It creates a population that has a great deal of the same genes as the mother clone. From this population, if enough plants are grown, individuals can be chosen that have all the same traits as the mother, for use in creating offspring that are similar (the same maybe) as the original clone.
Another problem that can arise is this- there are three possibilities for the expression of a monogenic (controlled by one gene pair) trait.
We have dominant, recessive, and co-dominant conditions.
In the dominant condition, genotypically AA or Aa, the plants of these genotypes will look the same (will have the same phenotype, for that trait).
Recessive- aa will have a phenotype
Co-dominant- Aa- these plants will look different from the AA and the aa.
A perfect example of this is the AB blood types in humans:
Type A blood is either AA or AO
Type B blood is either BB or BO
Type AB blood is ONLY AB
Type O blood is OO.
In this case there are three alleles (notated A, B, and O respectively).
If the clone has a trait controlled by a co-dominant relationship- i.e. the clone is Aa (AB in the blood example) we will never have ALL plants showing the trait- here is why:
Suppose the clone mother is Aa- the simplest possibility is that the dad used contributes one of his alleles,
let us say A. That mean the boy being use for the first backcross is either AA or Aa. We therefore have two possibilities:
- If he is AA- we have AA X Aa- 50% of the offspring are AA, 50% are Aa. (you can do the punnett square to prove this to yourself).
In this case only 50% of the offspring show the desired phenotype (Aa genotype)!
- If the boy being used is Aa- we have Aa X Aa (again do the punnett square) this gives a typical F2 type segregation- 25% AA, 50% Aa, and 25% aa.
This shows that a co-dominant trait can ONLY have 50% of the offspring showing the desired trait (Aa genotype) in a backcross.
If the phenotype is controlled by a dominant condition- see example #1- all 100% show the desired phenotype, but only 50% will breed true for it.
If the phenotype is controlled by a recessive condition- see example #2- only 25% will show the desired phenotype, however if used for breeding these will all breed true if mated to another aa individual.
Now- if the original dad (hashplant) donates an ‘a’ allele, we only have the possibilities that the offspring, from which the backcross boy will be chosen, will be either Aa or aa.
For the Aa boy, see #2.
For the aa boy (an example of a test cross, aa X Aa) we will have:
50% aa offspring (desired phenotype), and 50% Aa offspring.
Do you see what is happening here? Using this method of crossing to an Aa clone mother, we can NEVER have ALL the offspring showing the desired phenotype! Never! Never ever ever! Never!! LOL
The ONLY WAY to have all the offspring show a Aa phenotype is to cross an AA individual with an aa individual- all of the offspring from this union will be the desired phenotype, with an Aa genotype.
Now, all of that was for a Aa genotype for the desired phenotype. It isn’t this complicated if the trait is AA or aa. I hope this causes every one to re-evaluate the importance of multiple backcrosses- it just doesn’t work to stabilize the trait!
Also- that was all for a monogenic trait! What if the trait is controlled by a polygenic interaction or an epistatic interaction- it gets EVEN MORE complicated? AARRGH!!!
Really, there is no need to do more than 1 backcross. From this one single backcross, as long as we know what we are doing, and grow out enough plants to find the right genotypes, we can succeed at the goal of eventually stabilizing most, if not all of the desired traits.
The confusion arises because we don’t think about the underlying biological causes of these situations- to really understand this; we all need to understand meiosis.
We think of math-e.g. 50% G13, 50% hashplant
Next generation 50% G13 x 50% g13hp or (25% G13, 25%HP)
We interpret this as an additive property:
50% G13 + 25% G13 +25% HP = 75% G13 and 25% hashplant
This is unfortunately completely false- the same theory will apply for the so called 87.%% G13 12.5% HP next generation, and the following 93.25% G13, 6.25% HP generation; we’d like it to be true as it would make stabilizing traits fairly simple, but it JUST DOESN’T work that way. The above is based on a mathematical model, which seems to make sense- but it doesn’t- we ignore the biological foundation that is really at play.
I hope this was clear, I know it can get confusing, and I may not have explained it well enough- sorry if that is the case, I’ll try to clear up any questions or mistakes I may have made.
Have fun everyone while making your truebreeding varieties, but just remember that cubing (successive backcrosses) is not the way to do it!
-Chimera"
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Well he sure does make a solid point.
Man knows his science.
Thank you 
.
At the same time there aren’t many better options to be fair lol.
I’m guessing he just goes down the filial line after that?
I like this thank you.
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Haha, true on both counts. I personally like his no BS personality, especially since he has the experience to back it up.
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The guys very informative. He has been on the potcast, future cannabis project and a few other programs and he breaks things down nicely and is pretty down to earth
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