Let's Talk About How to Harness Hybrid Vigor and Potency

I just watched the best Weed Nerd show ever featuring a Breeders discussion at the Emerald Cup. It's Subcools latest Video and is a must watch for all breeders of cannabis.

I come from corn breeding, creating F-1 hybrids of seed corn. Let me show you have to create F-1 hybrids with your pot seeds.

Take your favorite 4 seed lines you're working with. Let's call them a, b, c, and d for now. Take any two say a and b and cross them. and keep a clone of one of them, either a or b. Cross a x b and get the seeds. Grow these seeds out and cross them back to your clone of a or b. Grow those seeds out and cross them back to your original clone. This is called cubing. You've made a cross, bred the prodigy back to the parent, grew those out and bred them back to the parent. When you do this you will notice the seed line begin to become uniform, however it may not become "better". Don't worry about that for now. The goodness is wound up inside the cube so to speak.

Now do the same thing with c and d. When you're done you'll have a cube of a x b and a cube of c x d. Now this is where the magic happens. You breed your two inbred cubes together for an F-1 hybrid. When you do this you'll get what's called hybrid vigor. Both of your cubes are wound up from inbreeding, when you cross the two together you'll get fairly uniform seed the first generation, the F-1 hybrid generation. The dominant genes of both cubes will come back in this cross and you'll get both potency and vigor at the same time and should be better than either a, b, c or d.

Can a or b be a clone or does it all have to be from seeds?

A clone is fine, all a clone is, is a cross. This also makes it easier. Cross to the clone, grow those out, choose a male if your clones female, cross the male progeny back to the clone. Grow those out and choose a male among those seeds and cross back to the clone. Now you have a cube of the clone seed. It's been inbred at least 3 times. The resulting seed will have 87.5% of the original clone genetics. It may or may not be "better" than the clone, but it will grow very similar to the clone. The idea is to cross 2 inbred lines. Lines that have been bred to themselves at least 3 times and that are different from each other. Crossing cubed seeds will cause a blow out of vigor and potency locked up inside the cubes. Now the ticket it to clone the best female of this F-1 cube cross and use that for yield and potency. Every clone of that clone will carry the hybrid vigor.

So you are saying that by first Cubing your lines, then doing a cross of the Cubed lines you can maximize the benefits of the hybrid vigour in your F1?

what would happen if you did this then cubed and crossed again?

• So you are saying that by first Cubing your lines, then doing a cross of the Cubed lines you can maximize the benefits of the hybrid vigour in your F1?
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Yes! Two inbred lines crossed will create an F-1 generation of seed. This seed will have hybrid vigor and tend to bring the dominant traits to the surface. For instance my Cindy 99.25 was Mr. Souls of Brother Grimm seeds most inbred version of Cindy. He had bred his progeny back to the Cindy clone 5 or 6 times. That seed was very Cindy 99, however the yield was terrible. The lowest yielding plant with the highest quality bud I've ever grown. It yielded about 1 oz in my custom DWC set up. My Williams Wonder line had fat leaves like an indica, grew short, but like Cindy, had a fruity and sativa like high. It was extremely inbred where every seed grew like clones. I crossed these seeds together to themselves for at least 5 years with every crop and the yield was about 4 oz. per plant. Both strains were very early with 7-8 week flowering times. Then I crossed these two inbred lines together and the vigor blow out was amazing. The F-1 hybrid clone yields 7-8 oz in the same set up with better taste and potency of either inbred line. That is a plant yielding 1 oz crossed to a plant yielding 4 oz created a plant yielding 7-8 oz. This happened because both seeds had been very inbred.

If you did this again you may not gain anything. The F-2 generation, (F-2's and F-1's crossed to each other) lose their vigor and the plants are more varied.

So basically if you cross 2 IBL you will get good increased vigour.

Make new IBL from those crosses and then cross the new IBLs and you should get an improved vigour again...?

but each time you make an IBL you will have a gradual decrease in vigour over time. So you can't have a cumulative effect to the hybrid vigour. Right?

The approach ive been meaning to try is finding an elite f1 of 2 ibl strains and instead of cubing, using another ible to back cross into because the issue i see with the cubing is that it may increase the likelihood of finding similar plants to the clone it does nothing for the homozygosity of the strain so if anyone decided tp use the seed for breeding purposes they would get more variation then they could handle. Thats just my hypothesis im not a big time seed dealer so i havent tried both methods or anything lol

non of this is as easy as it sounds or else we would have weed with 50% thc content by now ... I suggest you find strains you and your friends enjoy smoking, and try to find a decent male. If you store the pollen properly, you can easily use it on the progeny again thus stabilizing your new crosses. That's how I see it for now.

Can you please elaborate on the cubing process? I think I get it.
Step 1
Axb=ab
Step 2
Abxa=aba
Step 3
Abaxb

Is this correct?

It's close. Let's try to make this simple. It can get complicated but I'm trying to make the concepts very easy to understand. The idea is to cross two inbred strains that breed true. To create an inbred true breeding line of seed is simple. You grow out a population of seeds, lets say 10 seeds as is commonly sold. You choose the female you like the best and clone it. You'll have to clone all the females of the ten seeds, so you can breed back to one of them later on. You simple choose a male from those ten seeds to pollinate the female clone. Then with THOSE resulting seeds you choose a male and breed it back to the clone you've chosen. Then you grow THOSE seeds out and choose a male and breed it back to the clone you've chosen. Now of course you'll have to keep clones of your chosen female to do this. This creates a cube of he clone and the traits will be more like the chosen clone. Another way to make an inbred line of seed is to grow out a population of seeds and cross any male with any female within that population you've grown. Then grow those seeds out and do it again, then again and then once more for good measure. As you do this the population of seeds will become uniform and inbred. The idea is to cross these inbred seeds with ANOTHER set of inbred seeds for a F-1 or first generation hybrid seed. Two inbred lines crossed together can often create hybrid vigor in the first F-1 generation and the dominate traits of both inbred lines will express themselves.

WW,

If you were to use the seed technique you mentioned to get your IBL what would be the next step to maintain and preserve what you have created? Do you just do some clones and self fertilize them to have a supply of seeds? Or do you then have to maintain a mother?

Is there another way to maintain it?

I prefer to breed for seeds vs cloning or keeping a mother. I am able to store and transport seeds easily but I can't do the others as easily. Also if I suddenly needed to move or go away I would risk losing everything. That's not how I do things.

I also like like some variability in what I grow. I enjoy the surprise. I think that is part of the reason I like the Pakistani Chitral Kush used by Ace and Cannabiogen. It is uniform in some of its general traits but still has variation within those same traits. Different colours, scents, and tastes all within a similar theme. Very nice.

That is the kind of thing I would like to be able maintain. But I would also like to be able to take advantage of some hybrid vigour as well. Would I need to maintain a couple of similar yet different IBL that could be used as out crosses for vigour?

God, I love this thread.....people that spell reasonably well and have a bit of adventurous intelligence.Peace & be kind.

When breeding livestock I would maintain 2-4 different lines within the same breed, using those to outcrossing for vigour. This allows you to maintain the breed traits but still have vigour and variability within the desired traits or characteristics.

Can this same idea be applied to MJ breeding and vigour?

I am no proffesional, do not take this as an attack, I would just like to learn a bit.

Imho backcrossing does not amount to inbreeding. Its purpose is transmitting a limited set of traits from donor pool to recurent. That is all. Regarding stability, you cannot get more stable than your recurent clone.

Do not take my words for granted, if you planned any backcrossing in your battleplans, read about it a lot. Really, it seems to me the technique with the most misinformation and misunderstandings. From what I read it should be almost useless for outcrossers as unstable as canna is. It is very possible you planned a lot of futile work for yourself. It is more probable, that I do not really understand what is happening though.

Regarding real F1, shouldn't we focus first on getting as heterogenous parents as possible, from different pools, than looking for specific combining ability (or general at least)? The most simple desing seems to me to be: get 2 strains (AB) as different from each other as possible, as good for what you want as possible. Keep full sib lines, inbreed some. Topcross, A1 x B1,B2.... - test the progeny, the best is the B with best general combining ability. Topcross B(the best) x A1,A2... The best progeny defines the best parental combination. here you are looking at sca too.
The efficient approach would be clones and selfing. The most limiting thing, that I do not know how to overcome is that I do not feel comfortable with more pollen sources at the same place, at the same time. Thus inbreeding multiple lines will be the most time consuming (split work with friends?).

What do you guys think?

come on guys, we should get to the bottom of this.

When I said there is hardly any use to backcrossing, that is not very precise, when I think about it. Most autoflowering crossing will be prolly backcrossing. Experienced breeders will have favorite strains that they would like to maintain as they are and just tweak a trait or two.

The way most people talk about backcrossing, it seems to me they do not understand fully what they are doing, or, very possibly I do not. I am convinced backcrossing will not make anything more true breeding, stable, past the recurent parent stability.

Really the idea of F1 hybrids to me seems to be to cross the most distant pools available.

There certainly is a person with uderstanding deep enough to clear some of this.

William Wonder said:

Another way to make an inbred line of seed is to grow out a population of seeds and cross any male with any female within that population you've grown. Then grow those seeds out and do it again, then again and then once more for good measure. As you do this the population of seeds will become uniform and inbred. The idea is to cross these inbred seeds with ANOTHER set of inbred seeds for a F-1 or first generation hybrid seed. Two inbred lines crossed together can often create hybrid vigor in the first F-1 generation and the dominate traits of both inbred lines will express themselves.

Click to expand...

I saw that Weed Nerd episode you mentioned. Good stuff.

With regards to your post I quoted, how many filial generations does a breeder generally go through before they tag their seeds with IBL? Is that a set science, or a labeling/marketing thing? I am just curious. For example, Sannie has some F4's listed, his Jack F8, and then Herijuana IBL.

I just reread this thread, I understood this time haha. not as baked.

I have a cutting of Spacebomb X Chemo , only one of it's kind and I have no more seed, really fast maturing plant and a ton of resin.

If I grow out any male, I am thinking either Pennywise or a male F2 (spacebomb x medicine), use this male on my SpaceChemo,

out of the seeds I get, I chose another male use it on my SpaceChemo cutting,

use a male from those seeds and use it once more on my SpaceChemo cutting.

The seeds I get this third time are going to be 87% close to be my SpaceChemo !?

@greywind:
I doubt anyone sells IBLs. IBLs are for breeders and not for growers as far as I know.

@greensanta
what you indicated is a good strategy, but the Bx seeds will resemble the recurent genotype, not phenotype and since it is a cross, it will be a mess. Selfing and stabilizing the loved cutting first is an idea to think about.

William Wonder said:

I just watched the best Weed Nerd show ever featuring a Breeders discussion at the Emerald Cup. It's Subcools latest Video and is a must watch for all breeders of cannabis.

I come from corn breeding, creating F-1 hybrids of seed corn. Let me show you have to create F-1 hybrids with your pot seeds.

Take your favorite 4 seed lines you're working with. Let's call them a, b, c, and d for now. Take any two say a and b and cross them. and keep a clone of one of them, either a or b. Cross a x b and get the seeds. Grow these seeds out and cross them back to your clone of a or b. Grow those seeds out and cross them back to your original clone. This is called cubing. You've made a cross, bred the prodigy back to the parent, grew those out and bred them back to the parent. When you do this you will notice the seed line begin to become uniform, however it may not become "better". Don't worry about that for now. The goodness is wound up inside the cube so to speak.

Now do the same thing with c and d. When you're done you'll have a cube of a x b and a cube of c x d. Now this is where the magic happens. You breed your two inbred cubes together for an F-1 hybrid. When you do this you'll get what's called hybrid vigor. Both of your cubes are wound up from inbreeding, when you cross the two together you'll get fairly uniform seed the first generation, the F-1 hybrid generation. The dominant genes of both cubes will come back in this cross and you'll get both potency and vigor at the same time and should be better than either a, b, c or d.

Click to expand...

Hey! maybe this will sound stupid, but, can "a" "b" "c" and "d" be the same strain(diferent pheno) and get vigor from that strain only?

I don't think TGA is a great breeder as some make him out to be..ky