Questions about making F2

Zero0

Zero0

Well-known member
Hello there,

I have 1 pack of 12 seeds of a variety that interests me very much and I would like to make F2 but I wonder if with 12 seeds that is enough.

When I make F2s I am used to, for questions of viability and genetic diversity, of crossing at least 7 females with 7 males.

With 7 males and 7 females we obtain 49 different combinations which seems good to avoid inbreeding problems. Especially since, to be honest, this variety is already an inbreeded line (Bx3).

With luck on the 12 seeds I could have 4 good females and 4 good males but are 16 different combinations enough to continue the line with F3, F4 ?

Or better not to go beyond the F2 stage and cross it with another variety ?

Will the F2s themselves be good?


Thank you in advance for your advices.
👍
 
Zero0 said:
With luck on the 12 seeds I could have 4 good females and 4 good males but are 16 different combinations enough to continue the line with F3, F4 ?
Click to expand...
That depends on how far you would like to inbreed them. If the goal is to maintain as much genetic diversity as possible and you want to inbreed them multiple times, than more is deffinetly neccesarry. Of you are only making f2's then thats probably sufficient. Keep in mind that the better the f1 the better the f2. Multiple packs would give you not only a broader diversity, but also better f1 to breed with.

With open polllination, more is always better. When doing 1 to 1 pollinations, it all depends on the p1 selection.

I would reccomend doing an open pollination and also doing 1 to 1 matings of the best 3 females and males. Keep the open pollination as backup, and grow out the individual 1 to 1 matings, and see who has the best seed. Both Shanti and Nevil have rocked 1 to 1 matings. It's all about finding the two who click!.
 
Hello thank you very much for your answer.

I think I will make F2s in open pollination with 4 females and 4 males.as expected.

But if I take these F2s and I make for example :
15 F2 males crossed with 15 F2 females,
despite the lack of diversity of the F1s,

could this "refresh" the genetics to make F3s ?

Perhaps even with few F1 individuals at the base of the F2 cross, by crossing many F2 individuals it could bring out certain recessive genes and increase genetic viability?


" Both Shanti and Nevil have rocked 1 to 1 matings. It's all about finding the two who click!. "


Yes it's a good idea but it requires testing the males and that may be a little too much work for me.
😅
 
Zero0 said:
" Both Shanti and Nevil have rocked 1 to 1 matings. It's all about finding the two who click!. "


Yes it's a good idea but it requires testing the males and that may be a little too much work for me.
😅
Click to expand...
Very true. At the least you will be able to select the mother who gives you the best offspring.

Zero0 said:
But if I take these F2s and I make for example :
15 F2 males crossed with 15 F2 females,
despite the lack of diversity of the F1s,

could this "refresh" the genetics to make F3s ?
Click to expand...
I'm not sure, but I doubt it. You said that
this variety is already an inbreeded line (Bx3). So you may not get as much variety and reccessive genes exspressing themselves in the "f2" as one woupd normally expect. The further one inbreeds, the more locked genes become and the less vigor they can exsperience.


If it were me, and I wanted to maintain as much diversity, I'd open pollinate all of the f1, not just the four best. This helps prevent loss of desirable recessive genes which may not be present in my four keepers. I would then store the seeds from each female in its own vial. That way, I know which mother made the seeds and can select the one who gives me the plants which most resemble the archetype I'm looking for.

If you inbreed your two best lines for a few generations, you could recombine them later to make a "stabelized F1" which should "refresh" the line, so to speak.
 
Ok, that was basically what I thought.

Well I will make F2s for myself (indicating the different phenotypes of mothers) and then I will cross them with another variety.

It's true that with a variety that is a Bx3 it is very unlikely to find new recessive genes (whether they are desirable or not).

""If you inbreed your two best lines for a few generations, you could recombine them later to make a "stabelized F1" which should "refresh" the line, so to speak.""

Yes I could make some Bx2 with 2 good mothers phenotype of the F2 whit another male variety and recombine after.

But I don't think I'll go that far.
It is only to save seeds for my personal consumption. For the moment I don't plan to do real breeding projects.



Thanks again.
 
Last edited:
Zero0 said:
Ok, that was basically what I thought.

Well I will make F2s for myself (indicating the different phenotypes of mothers) and then I will cross them with another variety.

It's true that with a variety that is a Bx3 it is very unlikely to find new recessive genes (whether they are desirable or not).

""If you inbreed your two best lines for a few generations, you could recombine them later to make a "stabelized F1" which should "refresh" the line, so to speak.""

Yes I could make some Bx2 with 2 good mothers phenotype of the F2 whit another male variety and recombine after.

But I don't think I'll go that far.
It is only to save seeds for my personal consumption. For the moment I don't plan to do real breeding projects.



Thanks again.
Click to expand...
What strain?
 
Its Sour 2018 from Top Dawg, well its not a real Bx3 but there is the genetic code :

AJ Sour Diesel Cut] × [NYC Chem × Chemdog 91 Bx2
 
Zero0 said:
Its Sour 2018 from Top Dawg, well its not a real Bx3 but there is the genetic code :

AJ Sour Diesel Cut] × [NYC Chem × Chemdog 91 Bx2
Click to expand...
Hey Zero0
How to make f2 seeds?
You must start with f1 pedigree parents
which by your description you don’t have.
How many of those parental plants were feminised?
 
Sour 2018 are regular seeds and not one S1 or feminised strain are used in this cross.

The male used to make the backcross is also a regular strain.

But yes the cuts are females plants.
 
Last edited:
You must log in or register to reply here.
Back
Top