gene pool question

Humanrob

Well-Known Member
I started this in the auto section, but my question comes down to specifics on how genetic generational transfers take place. Reversing part of a single plant and having it pollinate itself, is as controlled and limited a gene pool as one can get short of cloning. I plan on doing that with some auto strains that I can't get anymore. Since I'm going to the trouble of setting up a pollination area I figured I might as well cross pollinate second strain. My goal is to have the highest rate of quality seeds possible, given that any cross has the potential if not the probability of producing some good and some bad outcomes.

My question is about making simple F1 crosses. If I cross two strains that have little or no genetic similarities - vs. - if I cross two strains that have significant genetic overlap, will the ones with more shared genes be likely more likely to produce a higher percentage of quality seeds?

Example
1. Cosmic Queen (Spacedawg x Chemdogging) x Sour Stomper (Sour Crack x Grape Stomper)
VS.
2. Double Grape (Sour Stomper x Grape Crinkle) x Sour Stomper

I would imagine that popping 10 seeds produced from the first example above could give me 10 different phenotypes, with a range of quality from great plants to mediocre ones.
What I'm wondering is, would the second example be more likely to produce a higher percentage of "great plants" simply because the range of genetic variables is more limited?

Or is the percentage of high vs. low quality prodigy a consistent percentage regardless of how much or little genetic variation there is between the parents?
 

Geneiac

Well-Known Member
A lot to unpack with your questions...let me try to get you heading in the right direction.

In general if you're crossing two random strains, you should expect quite a bit of variation in the progeny. Uniformity of the progeny requires a lot of careful planning and execution on the part of the breeder and can be accomplished in a few different ways depending on the goals of the project. For example you could create an inbred line from your crosses by mating your favorite male with your favorite female in the F1 population, then identify your favorite male/female in the F2s that display the same desirable characteristics as those selected for in the F1s, cross them, and repeat all the way through to the F7s at which point the population should be homogeneous. If you started with two inbred lines and crossed them the F1 generation would be hybrids between the two and should be homogeneous. Furthermore a desired trait from one plant could be introgressed into another through numerous rounds of backcrossing, which if the recurrent parent is an inbred line, should produce a stable population with the trait transferred from one parent into the recurrent parent.

It looks like one of your crosses will be a backcross (at least in theory but I don't know if the Sour Stomper parent in the double grape is the same sour stomper you plan to use in your cross) which to answer your first question if you like sour stomper, could lead to more great plants, or at least sibs in the F1 population that are slightly more similar.

I feel like the thing to do might be to make both your crosses but be prepared to sift through a lot of variation, but hey that's the fun part about breeding, you never know what your gonna get! Have fun with it and best of luck with your grow/breeding projects!
 

Humanrob

Well-Known Member
Thanks for the thoughtful reply. I've done a small amount of "pollen chucking" in the past with photos, and leaned heavily on my misguided understanding of "hybrid vigor" in attempts at making several series of interesting F1 crosses. I had some great luck, and some wasted space, but that was to be expected. My sources were a mix of seeds and clones of strains whose actual breeding were unverified, they all came from local dispensaries but they are sold to be grown and smoked, they made no claims about breeding them. It was fun, and I learned a little.

There was one piece of information you mentioned that clarified something for me:

If you started with two inbred lines and crossed them the F1 generation would be hybrids between the two and should be homogeneous.
I was not aware that there were any circumstances under which an F1 cross would produce homogeneous results. But that may have more to do with the rarity of truly well made IBL's. It's just not an expectation I've ever heard discussed.

From what I've gathered, it seems to be rare for strains commonly commercially available to be fully stabilized, I highly doubt the seeds I'm buying are. But if I'm understanding you correctly, if the Mephisto strains that I've purchased were stabilized (F7), after crossing them their offspring should be consistent also. Wow, that would be something. Mephisto often references their releases, I think F3 or F4 are about as good as they get.

It looks like one of your crosses will be a backcross (at least in theory but I don't know if the Sour Stomper parent in the double grape is the same sour stomper you plan to use in your cross) which to answer your first question if you like sour stomper, could lead to more great plants, or at least sibs in the F1 population that are slightly more similar.
I'm not attempting to breed for any specific characteristics. It's much simpler than that. Primarily I'll be self-propagating some strains that are no longer available, by using CS on a single branch of a feminized auto. The additional crosses are secondary, it's mostly about efficiency; if I've already staged the setup for one plant, adding a second one is only marginally more work with the possibility of a great payoff. So this process is all about choosing that second pollen recipient.

I have no time or space (or desire, really) to pheno hunt or go through numerous cycles of backcrossing. I have very limited resources at this point, so in terms of my secondary one-off crosses, at the core I'm trying to decide if it's worth doing. I'm not looking to repeat the somewhat random results I got in the past, my grows these days are too small to have a significant number of bad outcomes. I'm wondering if leveraging genetic commonality would narrow the variables and improve the odds that popping these seeds down the road will at least mostly produce plants of similar quality as the strains they originated from. If that's even knowable.
 

Geneiac

Well-Known Member
I was not aware that there were any circumstances under which an F1 cross would produce homogeneous results. But that may have more to do with the rarity of truly well made IBL's.
Exactly! I feel like most strains today result from phenohunting/finding that one keeper out of 1000 ie clone only strains...i guess thats where they need to start but my point is the process of going from that mother plant that was ID'ed to a seed stable strain take ALOT of time/money/effort and skill to pull off and just simply doesn't happen all too much...if anyone knows of breeders that sell inbred lines/lines labelled as F7s, I would love to know about them as those would be the best lines to incorporate into a breeding project.

But yeah, if that sour stomper is legit (you like it) and there's a reasonable chance that the SS parent of the double grape is related to your SS to be used in the cross, I think you'll have better luck finding keeper plants from that cross as the offspring will tend towards the SS side of the spectrum, perhaps weeding out some of the middle of the road phenos. I would still expect quite a bit of variation in that population however!

Have fun with it :bigjoint:
 

ICGA

Well-Known Member
I started this in the auto section, but my question comes down to specifics on how genetic generational transfers take place. Reversing part of a single plant and having it pollinate itself, is as controlled and limited a gene pool as one can get short of cloning. I plan on doing that with some auto strains that I can't get anymore. Since I'm going to the trouble of setting up a pollination area I figured I might as well cross pollinate second strain. My goal is to have the highest rate of quality seeds possible, given that any cross has the potential if not the probability of producing some good and some bad outcomes.

My question is about making simple F1 crosses. If I cross two strains that have little or no genetic similarities - vs. - if I cross two strains that have significant genetic overlap, will the ones with more shared genes be likely more likely to produce a higher percentage of quality seeds?

Example
1. Cosmic Queen (Spacedawg x Chemdogging) x Sour Stomper (Sour Crack x Grape Stomper)
VS.
2. Double Grape (Sour Stomper x Grape Crinkle) x Sour Stomper

I would imagine that popping 10 seeds produced from the first example above could give me 10 different phenotypes, with a range of quality from great plants to mediocre ones.
What I'm wondering is, would the second example be more likely to produce a higher percentage of "great plants" simply because the range of genetic variables is more limited?

Or is the percentage of high vs. low quality prodigy a consistent percentage regardless of how much or little genetic variation there is between the parents?
It doesn't matter how much variation there is as far as how many will be good or bad. If u have 3 bad parents and 1 good one you will get less keepers maybe none. if 2 of the bad parents are the same it only means that those "cross linked" chromosomes will express themselves more frequently with the traits from those 2 related parents. Some "good" plants have "bad" traits masked by recitavism therefore their progeny will be more likely to have bad phenotypes. Like a plant that's half or even 25% raw unrefined landrace where they used the land race to shorten the flower time and picked a keeper with more refined traits from the other parent but short flowering will often yield many bad phenotypes when outcrossed because those desirable refined traits will only express in progeny that is homozygous recessive at the allels that code for the desired traits and the majority will be heterozygous dominant or homozygous dominant therefore not expressing the desired recessive smell and resin traits which can only be observed in the homozygous receive minority population.
 
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