Questions on Polyhybrids

[africaseeds]

By definition a polyhybrid is a cross where the male or female is an F1.
Is a cultivar a polyhybrid if one of the parents was a polyhybrid (but not an F1) so for example F2 Polyhybrid x F3?

From my understanding the legendary Blue Dream:
https://en.**********.eu/strain-info/Blue_Dream/Humboldt_Seed_Organisation/
Is: Blueberry x Super Silver Haze .
Super Silver Haze is a polyhybrid from what I understand so if anything times a polyhybrid is also a polyhybrid then that would make Blue Dream also a Polyhybrid.

Curious what your thoughts are?

 

[Carraxe]

Anything you mix a polihybrid into becomes a polyhybrid.

 

[SeriouslySilly]

Yes.

 

[GMT]

Yes but if you inbreed a polyhybrid, it eventually becomes a P1 for breeding, which when crossed with another P1 creates F1 offspring.

 

[africaseeds]

Yes but if you inbreed a polyhybrid, it eventually becomes a P1 for breeding, which when crossed with another P1 creates F1 offspring.

This is interesting, that was actually my next question how do I stabilize a polyhybrid. Where can I read more about this topic?
Thanks

 

[GMT]

You're on the perfect site to read about such things. Look in the breeders lab section and you'll be reading for months.

 

[Happy Times]

This is interesting, that was actually my next question how do I stabilize a polyhybrid. Where can I read more about this topic?
Thanks

First thing I think of is “cubing”, which is how C99 came into existence

Might be some threads on it

basically cross selected bad-ass female to a best/most appropriate male, grow out seeds, make male selection from this seed pop, and cross back to original female. Keep repeating finding male(s?) from each successive batch of seeds, and in each seed generation the % of the original mom becomes higher and higher- 50% in first cross, then 75%, 88%, ...

I know there a lot more subtleties to breeding than this but I’m no expert, yet! The above is keeping things really simple for one approach to stabilizing a polyhybrid

 

[africaseeds]

First thing I think of is “cubing”, which is how C99 came into existence

Might be some threads on it

basically cross selected bad-ass female to a best/most appropriate male, grow out seeds, make male selection from this seed pop, and cross back to original female. Keep repeating finding male(s?) from each successive batch of seeds, and in each seed generation the % of the original mom becomes higher and higher- 50% in first cross, then 75%, 88%, ...

I know there a lot more subtleties to breeding than this but I’m no expert, yet! The above is keeping things really simple for one approach to stabilizing a polyhybrid

Wouldn't inbreeding be a better approach here?

 

[Breadwizard]

Cubing is a form of inbreeding

 

[GMT]

Cubing is not a form of inbreeding.
Inbreeding reduces the variations (excluding the mistakes and meiosis that arise) within a line. If you cube, you are attempting to reproduce the specifics of a particular plant, which may itself be a polyhybrid. You can't create an f1 batch from a polyhybrid parent.
Only multiple generations of selections reduce variation.

 

[Breadwizard]

The first step is an outcross, true. But isn't every cross back to the clone inbreeding? It's not adding genetic variability.

 

[hush]

Yes, cubing is still inbreeding. From a technical standpoint anyway. Inbreeding isn't only a process involving organisms from the same generation. Mixing a grandmother and her grandson would still be inbreeding.

 

[Betterhaff]

If the parent being backcrossed to is heterozygous for desired trait you’ll end up getting the same result by continued backcrossing to that parent (for desired trait). A desired goal of inbreeding is to lock down traits of a parent (homozygosity) so it breeds true (for those traits).

Backcrossing can be used as a tool to determine the zygosity of a parent.

 

[GMT]

No back crossing/ cubing IS NOT inbreeding.

Go and do some reading before arguing about stuff you don't understand.

Inbreeding is the removal of genes through successive generations of selections. When you backcross to the same polyhybrid over and over, you are attempting to replicate that polyhybrid. Therefore the goals are different. The results are different. they have different terms.

When you remove genes within the population, that population becomes more uniform. Eventually, a lot of the genes that can be found within both DNA strands end up being the same. Therefore when you cross one of these plants, the genes they pass on are the same in their offspring.
When you backcross to a poly hybrid, you are trying to replicate that polyhybrid. Therefore you are not trying to remove genes but rather trying to capture them all in one or more of the offspring. When you look at the strands of DNA, the genes are not the same on each strand. Genes will be passed on at random. Seeds generated from a polyhybrid, whether first generation or backcrossed for years, crossed to a P1 parent ( generations of INBREEDING) will NOT produce a stable generation of seeds with little variation. These seeds are not F1" s.

Neither is better or worse, its all about choices. But to make a choice, you have to be informed about the choices and what the differences are. If you aren't you can make the wrong choice.