I’ve been kicking around an idea that I’d like to articulate and ask for any input.
My primary goal is to create a male version of a clone-only female. Not just any male, a male that is as identical to the female in expression as possible while making these desirable traits homozygous or “true-breeding”.
I would be back-crossing the target female successively to achieve this. Back-crossing is a process whereby the target plant is pollinated by successive progeny in order to reinforce the genetic contribution of the target female to resultant progeny.
To make this concept more visual:
As a male is chosen from each new back-crossed generation and used to pollinate (
or cross back to) the target female, the phenotype of the target female is further reinforced in subsequent progeny. Usually, to the extent a strain is backcrossed, the process stops around BX#3 (
cubing) as the resultant plants would have about 94% contribution from the target female. This is considered a good stopping point since the target female’s phenotype will theoretically be “locked down” in the progeny.
Now, if we continue the back-crossing beyond the third generation, we have the following sequence:
I expect to have to use this process with my Green Crack x Granny Skunk project as it’s main goal was to introduce one new trait (
better structure) to the Green Crack while keeping everything else. A BX3 or “cube” would give me a plant that is 94% Green Crack with the 6% being the hardy structure of the Granny Skunk (
if selection and genetic mixing allow).
What if I would like a near 100% phenotypic representation in seed form? The obvious answer would be to continue the back-crossing process to at least the BX8 generation (
99.8%). The issue is male selection (
selecting a single male expressing target female traits) from each round introduces an opportunity for poor selection that can carry recessive traits that will express later down the line. Since I aim not only to “lock-down” the phenotype of the target female, but also to “lock-down” the genotype such that these expressed traits are true breeding, I wonder if the lengthy process is worth the effort given so many opportunities for missteps.
I am considering taking the
Chem’91-SkunkVA (and/or)
Hells Angels OG to at least a BX8 generation in an effort to create a true-breeding male version of these elites without having to collect pollen from dozens of males each BX round. I realize this process will take considerable time and effort, so if anyone has any insights into such a prolonged back-crossing endeavor or any thoughts/considerations/musings you could share, please do.
Thanks
. Sorry, I am not currently growing the Blueberries and Chocolate. I made a few posts in the Useful Seeds thread about the Chocolate Diesel that was used in that cross (will be easy to find with the thread search function). 
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