That's how I understand F2's, but I didn't know that they're only created by crossing different phenos of the F1 cross.

I'm running a small batch of my own F2's this year for the first time, it will be interesting to see what I get. The original cross is Cali O x Blueberry (unknown). The F1's came out mostly looking and smelling very Cali O, double-serrated leaves, extremely strong citrus/orange smell, but there were a few with lavender pistils and a lavender/floral scent. I did an open pollination of all the fruitiest phenos, because those were what I prefer.

Typically in the F2's youll see some more recessive traits that arent visibly present in the two parents. Definitely a broader variation of phenotypes. You can cross identical phenos and still bring out different traits

cannarado said:

Typically in the F2's youll see some more recessive traits that arent visibly present in the two parents. Definitely a broader variation of phenotypes. You can cross identical phenos and still bring out different traits

Click to expand...

So you should select the best male and female pheno from the f2's breed those two together and that will tighten the gene pool creation less variation? How many generations does it take usually take to tighten the gene pool up enough so there will be minimal variation in phenos?

Seamaiden thats what I don't understand from your statement it seems as though that there was less variation in the f1's you made then there will be in the f2's. Wouldn't another round of selective breeding close the gene pool? It seems as though that when you breed the f1's together you open the gene pool instead of close it? LOL.. maybe I just don't understand it. - SE

Steel Erection said:

So you should select the best male and female pheno from the f2's breed those two together and that will tighten the gene pool creation less variation? How many generations does it take usually take to tighten the gene pool up enough so there will be minimal variation in phenos?

Seamaiden thats what I don't understand from your statement it seems as though that there was less variation in the f1's you made then there will be in the f2's. Wouldn't another round of selective breeding close the gene pool? It seems as though that when you breed the f1's together you open the gene pool instead of close it? LOL.. maybe I just don't understand it. - SE

Click to expand...

Cannarado hit the nail on the head. When you make and F2 the gene pool is tightened, but certain genes that were not expressed in that first generation will be "uncovered." For a full explanation do a Google search on "Punnett Square Examples." A picture of how it works is a lot clearer than I can explain it. Basically all genes operate in pairs and for a recessive trait to show up both genes in the pair need to be recessive, which takes one generation past the F1 to present itself, if it is indeed a true F1.

As for how many generation it takes to stabilize the strain, that is very strain dependent. I would say at least three but usually more. It all depends on if the first generation was a true F1 (totally unrelated parents from different gene pools) well as how the F2 and subsequent generations were bred, plus many, many other factors. Also when you start to inbreed a strain often you begin to get inbreeding depression which result can result in loss of vigor, yield, and potency. In my experience that first F1 cross is often the most stable (provided it is a true F1) even more so often than F3's or F4's or back-crosses, and they ALWAYS have the most vigor.

Blaze-So to be a true f1 would be the initial cross of two totally unrelated strains say like breeding a Chemdog male to a Skunk #1 female. Those seeds would be the f1 seeds. Then you take a male and a female from those f1 seeds and breed them resulting in f2 seeds. Correct?

I used to breed dogs and I would selectively inbreed to eliminate negative traits once I got what I wanted from inbreeding I would out cross to another heavily inbred dog of another family that held attributes I thought would benefit the dogs I was working with. And that cross was usually just dynamite.

I grasp the concept it just doesn't seem right that even though you are essentially tightening up the gene pool there will be more variation in the f2 generation then the f1. I also understand dominant and recessive traits but with each generation shouldn't the likelihood of a recessive trait showing up be lessened? I'm scratchin my head here. -lol thanks-SE

Wouldnt the female plant have a more deciding factor on how an F1 or F2 would look?Seems like it would keep the female structure more often than the breeding male to me.

Steel Erection said:

Blaze-So to be a true f1 would be the initial cross of two totally unrelated strains say like breeding a Chemdawg male to a Skunk #1 female. Those seeds would be the f1 seeds. Then you take a male and a female from those f1 seeds and breed them resulting in f2 seeds. Correct?

I used to breed dogs and I would selectively inbreed to eliminate negative traits once I got what I wanted from inbreeding I would out cross to another heavily inbred dog of another family that held attributes I thought would benefit the dogs I was working with. And that cross was usually just dynamite.

I grasp the concept it just doesn't seem right that even though you are essentially tightening up the gene pool there will be more variation in the f2 generation then the f1. I also understand dominant and recessive traits but with each generation shouldn't the likelihood of a recessive trait showing up be lessened? I'm scratchin my head here. -lol thanks-SE

Click to expand...

It makes sense to me because the recessive phenotypes will be expressed more readily, or at least have the potential to be expressed. And with the previous generations, since those traits are indeed recessive we may not even observe them until they're able to be expressed in subsequent generations.

I wonder what role epigenetics plays in breeding cannabis.

Trying to lock down a particular trait takes a lot of time. First you have to decide whether you are going to work backcrosses to an original mother or are you going to breed the offspring to create F2,F3,F4 lines. I think its quicker to lock down traits in seed by backcrossing to a specific plant that you want to try to mimic. Continually breeding offspring F2,F3,F4 gens will take more time to lock in traits but in that you can find more recessive traits that you may like more. Lots of people think that cubing genetics is enough to lock down traits. I am not 100% on that one. Especially after reading Chimeras thread on the theory of cubing genetics.

How many F-generations it takes to stabilize a given trait largely depends on the trait's homogeneousness. To stablize ALL traits takes many many generations and years of work, not only F-gens, but back-crossing to the P1 stock and/or other previous F-generations, and lets not forget testing, testing, testing. It takes time, patients, dedication, space, and throw in a dash of luck, too. You'll be smoking lots of different phenos, trying to decipher the nuances between them.