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Dumb question about auto flower
- Thread starter John LOQUE
- Start date
Maybe I misunderstood your query. Crossing Female auto with regular auto, yes, auto.
Fem auto w/ photoperiod male (regular)....you'll get approx. 25% first run auto x photoperiod.
Is that what you are asking?
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socioecologist
Member
Theoretically, as this has not been confirmed with genomics data yet, but the normal experience for auto x photo lines:
F1 = 100% photo
F2 = 25% auto (aa), 50% photo dominant, carrying recessive auto allele (Aa), 25% photo only (AA)
Robert Clarke , from marijuana botany
Occasionally hybrid offspring will prove inferior to both parents, but the first generation may still contain recessive genes for a favorable characteristic seen in a parent if the parent was homozygous for that trait. First generation (F1) hybrids are therefore inbred to allow recessive genes to recombine and express the desired parental trait. Many breeders stop with the first cross and never realize the genetic potential of their strain. They fail to produce an F2 generation by crossing or self-pollinating F1 offspring. Since most domestic Cannabis strains are F1 hybrids for many characteristics, great diversity and recessive recombination can result from inbreeding domestic hybrid strains. In this way the breeding of the F1 hybrids has already been accomplished, and a year is saved by going directly to F2 hybrids. These F2 hybrids are more likely to express recessive parental traits. From the F2 hybrid generation selections can be made for parents which are used to start new true-breeding strains. Indeed, F2 hybrids might appear with more extreme characteristics than either of the P~ parents. (For example, P1 high-THC X P1 low-THC yields F1 hybrids
of intermediate THC content. Selfing the F1 yields F2 hybrids, of both P1 [high and low THC] phenotypes, intermediate F1 phenotypes, and extra-high THC as well as extra-low THC phenotypes.)
Below: substitute auto/ photo for pineapple/pine. Viola`!
http://www.marijuanagrowing.eu/grow-faq/creating-true-breeding-strains-vic-high-t24986.html
The F1 cross (won't be 100% photo as described above). Mendel/Punnett Squares show different)
Now most will find it tough to pick males with the gene for pineapple flavour since males don't produce female flowers. Therefore, they will select males randomly and blindly with respect to this trait. The ratio of* P to p genes of the male F1 generation to be used in the first backcross will be 2:6. Another way to look at it is to say that the P gene fequency is 25%. This means that one out of four pollen grains will contain the gene for pineapple flavour.
Here is how this plays out in the first backcross.
The B1 cross
Now it's this first backcross that first creates an individual that is homozygous (PP) for the pineapple flavour. However, again because of our limited selection abilities, we choose males randomly. From the random males we should expect* three out of eight pollen grains to to contain the gene for pineapple flavour. The P1 female will still contribute one P gene for every p gene.
The second backcross (Squaring) will produce the following:
Therefore, 68.75% will have pineapple flavour and 31.25% will have pine flavour. The frequency of the P gene has risen to 7/16 or* 43.75%.
And finally, the third backcross (Cubing) will net the following genotypic ratios:
Therefore, 71.875% will have pineapple flavour after cubing has been completed. Roughly 22% (7/32*100) of the cubed progeny will be true breeding for the pineapple flavour. The frequency of the P gene has risen to roughly 47% (30/64).
In conclusion, if the backcrossing continued indefinately with random selection of males and with large enough of a population size, the frequency of the P gene would max out at 50%. This means that the best that can be expected from cubing is 25% true breeding for pineapple flavour and 75% that will display the pineapple flavour. You would never be rid of the 25% that would maintain the pine flavour. This model would hold true when trying to cube any heterozygous trait.
Occasionally hybrid offspring will prove inferior to both parents, but the first generation may still contain recessive genes for a favorable characteristic seen in a parent if the parent was homozygous for that trait. First generation (F1) hybrids are therefore inbred to allow recessive genes to recombine and express the desired parental trait. Many breeders stop with the first cross and never realize the genetic potential of their strain. They fail to produce an F2 generation by crossing or self-pollinating F1 offspring. Since most domestic Cannabis strains are F1 hybrids for many characteristics, great diversity and recessive recombination can result from inbreeding domestic hybrid strains. In this way the breeding of the F1 hybrids has already been accomplished, and a year is saved by going directly to F2 hybrids. These F2 hybrids are more likely to express recessive parental traits. From the F2 hybrid generation selections can be made for parents which are used to start new true-breeding strains. Indeed, F2 hybrids might appear with more extreme characteristics than either of the P~ parents. (For example, P1 high-THC X P1 low-THC yields F1 hybrids
of intermediate THC content. Selfing the F1 yields F2 hybrids, of both P1 [high and low THC] phenotypes, intermediate F1 phenotypes, and extra-high THC as well as extra-low THC phenotypes.)
Below: substitute auto/ photo for pineapple/pine. Viola`!
http://www.marijuanagrowing.eu/grow-faq/creating-true-breeding-strains-vic-high-t24986.html
The F1 cross (won't be 100% photo as described above). Mendel/Punnett Squares show different)
Now most will find it tough to pick males with the gene for pineapple flavour since males don't produce female flowers. Therefore, they will select males randomly and blindly with respect to this trait. The ratio of* P to p genes of the male F1 generation to be used in the first backcross will be 2:6. Another way to look at it is to say that the P gene fequency is 25%. This means that one out of four pollen grains will contain the gene for pineapple flavour.
Here is how this plays out in the first backcross.
The B1 cross
Now it's this first backcross that first creates an individual that is homozygous (PP) for the pineapple flavour. However, again because of our limited selection abilities, we choose males randomly. From the random males we should expect* three out of eight pollen grains to to contain the gene for pineapple flavour. The P1 female will still contribute one P gene for every p gene.
The second backcross (Squaring) will produce the following:
Therefore, 68.75% will have pineapple flavour and 31.25% will have pine flavour. The frequency of the P gene has risen to 7/16 or* 43.75%.
And finally, the third backcross (Cubing) will net the following genotypic ratios:
Therefore, 71.875% will have pineapple flavour after cubing has been completed. Roughly 22% (7/32*100) of the cubed progeny will be true breeding for the pineapple flavour. The frequency of the P gene has risen to roughly 47% (30/64).
In conclusion, if the backcrossing continued indefinately with random selection of males and with large enough of a population size, the frequency of the P gene would max out at 50%. This means that the best that can be expected from cubing is 25% true breeding for pineapple flavour and 75% that will display the pineapple flavour. You would never be rid of the 25% that would maintain the pine flavour. This model would hold true when trying to cube any heterozygous trait.
socioecologist
Member
I'm truly intrigued by this arid. Can you expand on a bit on your experience? How often do you run across auto progeny in the F1? Is it more likely to happen when crossing to early photoperiod plants?
Been growing for 40+ years, the last 9 w/ autos, creating strains (auto x auto). We've successfully crossed several auto x photos. When that is done, crossing auto with photo we automatically know F1's of a x ph will be approx. 25% auto, the remaining mixed traits Punnett's square. So, Punnett square is a diagram that is used to predict an outcome of a particular cross or breeding experiment.
Grow those out to select auto dominant strains, then back cross.
Back cross grows create more auto traits, then cross again with auto dominant. We take 5-6 generations of grows to create a stable auto.
Some do it differently....that's how we roll.
Good luck with your experiments. Time to get your hands in the dirt and try it for yourself! GROW ON!
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socioecologist
Member
That's awesome, very cool that you are here to share that wealth of experience.
The OP wants to know if an auto (aa) x photo (AA) will yield any autos in the F1 generation. The short answer should be: NO (all F1s will be Aa). The ratios you describe above would be present in the F2 generation (25% aa, 50% Aa, 25% AA), not the F1--that's why I've been confused / intrigued by your responses to inquiries re: auto x photo crosses. Autoflowering appears to be a monogenic trait (again, we are awaiting genomic confirmation of this), so the only way autos could appear in the F1 is if your photo parent plant recessively carries the auto allele (Aa). If that was the case, 50% of F1 progeny would be auto and 50% photo.
Not trying to troll here, just making sure that the information is accurate.
Not trying to troll here, just making sure that the information is accurate.
Grow and see/experience for yourself.
Or if you want purely academics (not doing it yourself), READ, Google info, contact Oregon State Univ ....they have a great colleges of Forestry, Agriculture, Science. Ask them!!!
Grow and see/experience for yourself.
Or if you want purely academics (not doing it yourself), READ, Google info, contact Oregon State Univ ....they have a great colleges of Forestry, Agriculture, Science. Ask them!!!
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socioecologist
Member
I do. I've asked the previous questions purposefully and in a respectful way because what you posted was incorrect--I assume that it was an unintentional oversight on your part? The OP asked if they will see AF traits in the F1 generation. They will not. Editing your previous post to say AF will appear in the F2 instead of the F1 would fix the oversight, would it not?
Cameltom
Member
Air Killed it! there will be about 25% Autos in the F1 generation. But dont take my word for it. look it up..
also i would like to know where you found your theories.i would also like to see some statistics. As all of Mendels work/studies are highly looked up to in all areas of agriculture
also i would like to know where you found your theories.i would also like to see some statistics. As all of Mendels work/studies are highly looked up to in all areas of agriculture
Thanks, Cameltom. I suggested investigating, too, to the academian, provided articles/explanation for back up. From all our years of breeding....25% F1 when you auto ruderalis x photo ....that's been our experience. Mendel and Punnett declare the same.
I can see it differently (percentage/ratio) if not a true auto ruderalis x photo.
Genic rules apply whether it is terpenes or crossing strains. There is a formal order to genetics....nothing can change that!! So, f1 25% change, F2 > or ~25%, then back crossing creates more of what you want to achieve.
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socioecologist
Member
This is getting flat out weird dude. Yes, I emailed you from my real life university account to clarify your statements, as you have posted this "AF in the F1" line a couple times now in different threads. NO, you did not provide articles or explanations--there aren't any publications on photoperiodicity of cannabis (one of the reasons for my interest). The email exchange:
socioecologist said:
And your reply:
aridbud said:
I really appreciate you taking the time to respond to my initial query, but your response directly contradicts what you are claiming now in this thread. When pushed to elaborate on how a recessive trait (AF) would appear in the F1, you posted information here on terpene inheritance from Rob Clarke. That's a different model altogether!
Your posts were interesting to me because I haven't run across anyone (including myself) who has produced viable AF genes in an F1 cross between photo x AF, and I work with populations of cannabis plants that would be conducive to finding such a rarity. Just because someone has an ".edu" in their email address doesn't mean they don't have dirt under their fingernails, eh?
I got the answer I suspected (i.e. your previous posts about AF in the F1 are bullshit, for one reason or another), all I would ask is that you stop repeating incorrect information to those who legitimately seek knowledge.
Cameltom
Member
YOU MY FRIEND ARE BEING RUDE AND FLAMING.
all you have to do post your proof. air did!
socioecologist
Member
YOU MY FRIEND ARE BEING RUDE AND FLAMING.
all you have to do post your proof. air did!
Did you read where he admits 25% show up in the F2 and not in the F1? That'd be in the post just above yours calling me rude.
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