[GrowingHigher]

Cannabigerol (CBG) dominant plants are becoming the rage for next season among smokeable/raw hemp flower growers (almost entirely due to the USDA interim rule making most CBD varieties susceptible to testing hot).

So I want to discuss and compile some information about breeding for CBG varieties that will pass for compliance.

Firstly some background:

Identification of a New Chemotype in Cannabis sativa : Cannabigerol - Dominant Plants, Biogenetic and Agronomic Prospects
-CBG dominant plant first ID'd by Fournier at al, 1987.

The draft genome and transcriptome of Cannabis sativa


Gene duplication and divergence affecting drug content in Cannabis sativa
-showed there were multiple THCAS/CBDAS sequence homologs in individual plants

Sequence heterogeneity of cannabidiolic- and tetrahydrocannabinolic acid-synthase in Cannabis sativa L. and its relationship with chemical phenotype.
-different synthases have different efficiencies

A physical and genetic map of Cannabis sativa identifies extensive rearrangements at the THC/CBD acid synthase loci.
This paper shows (at least for one variety of fiber hemp (Finola) and one marijauna (Purple Kush)) that the fiber-derived linked cannabinoid synthases (CBDAS, THCAS) are very different in their arrangement. This suggests:
- A lot of derivation once the two gene pools separated.
- Residual THC production in hot hemp varieties is probably produced by the CBCAS, which are unlinked from THCAS/CBDAS
- -the putative THCAS identified by Kojoma et al, 2006 in hemp are actually CBCAS. Both Purple Kush and Finola had CBCAS.

The Inheritance of Chemical Phenotype in Cannabis sativa L
This paper talks about chemotype inheritance and crosses a fiber-dervied CBG variety to a high THC drug variety. in the F2 the CBG segregates, and again produces no detectable THC:

The inheritance of chemical phenotype in Cannabis sativa L. (IV): cannabinoid-free plants.
This 2009 deMiejer Paper talks about the inheritance of cannabinoid free plants and an alternative CBG producing genotype derived from the USO-31 hemp variety. This variety apparently has two gene knockouts; one that prevents cannabinoid production when homozygous and severly suppresses it in heterozygotes, and another that blocks CBD production causing CBG to accumulate. The USO-31 derived region responsible for CBG accumulation produces extremely pure CBG (99.75% of cannabinoids) with residual CBD (0.25%).

DeMiejer also has a 2014 book chapter in the "Handbook of Cannabis" that discusses a similar cross using fiber-derived versus a marijuana-derived (high-THC variety that had a CBG variant) CBG gene region. The fiber-derived linked synthase region produce residual amounts of CBD and almost no THC. Whereas the marijuana derived CBG region variant produces residual THC.


Breeding forward:
Recently Oregon CBD made their CBG variety announcements on instagram. In their post, they explained how they crossed a marijuana derived CBG variety (that produces THC at about 1:27 ratio CBG:THC) with a (probably) hemp derived CBG variety that has a ratio of 1:100-200. (you can see their tests here).

By doing this they have rather cleverly prevented people from producing F2s that will all be compliant (though on a field level the average still would be). Oregon CBD also loves to pretend that you cant use F1 material as breeding material, when in fact F1 material is often the starting point to develop variation in the creation of new lines. I suspect that, because the one of their CBG variants is almost certainly fiber-derived, compliant 1:100-200 ratio plants will emerge easily among the F2 progeny, which would be truebreeding for CBG if these are inbred to F3+. Of course the MTA they have you sign means you aren't even permitted to save seed for on farm use, let alone breed with any of their germplasm, anyway.

Oregon CBD also made an argument that 8 gene/pseudogene regions may be responsible for residual THC production. Medicinal Genomics also has made this claim (these companies work together, so MG is probably the source of this info). But active THCAS and CBDAS are tightly linked, with residual THC from the CBCAS as well. I am not sure how many active copies of each synthase exist among various varieties.

Ultimately, I suspect for those looking to breed for CBG, if you use a fiber-derived CBG gene region, you will be able to easily produce a true-breeding, CBG-dominant, THC-compliant hemp variety, with crosses mostly behaving as a simply inherited single locus with some residual THC from CBCAS. The negative of this is that you will be starting from a low point for total cannabinoid synthesis. But backcrossing the CBG gene region into high-cannabinoid drug plants or populations should overcome this.

CBG seed sources:

CanapaRoma- 8%CBG under 0.1%THC. No MTA. putatively truebreeding for complaint (at about a 1:65 THC:CBG ratio), fiber derived CBG variant.

Sovereign Fields-$2/seed, unknown specs. MTA required

HGH seed- 15+% CBG, Matterhorn CBG, $1+/seed. not sure about MTA

Oregon CBD- 15+% CBG, $1/seed, MTA required

European fiber varieties (I am not certain, but these are probably protected by plant variety protection (PVP), meaning you can save seed for on-farm use and breed with them):

Santhica-27: monecious 1-3% CBG, CBD residual

Carma - monecious ~3% CBG

USO-31- monecious. low cannabinoid, some cannabinoid free plants, some CBG dominant plants with very little residual CBD production.

Please share any relevant information on CBG breeding and seed sources. Thanks!

[hellfire]

*bites apple*

Can we get some test results in here? Preferably at least 3 different labs for 1 strain, repeated trials ensure accuracy.

Eventually we should have stabilized F7s and new P1 hemp populations. I would think some CBD breeders are nearing this but due to the market demand for feminized seeds there seems to be a lack of sexual breeding and mostly reversing.

How low is 'low cannabinoid' on USO 31? How many generations does it take to get to 15%+ CBG? It seems to have happened rather quick, at least by these claims. Maybe I'm old hat, skeptical, and think this would take longer than it has.

I got a hemp spam email the other day about claimed 17% CBG seeds, minimum order 300k
Some people are going to lose money buying "CBG seeds" this year. There's seed conmen around looking for starry dollar sign eyed hemp farmers that don't know anything about cannabis.

[GrowingHigher]

Originally Posted by hellfire

*bites apple*

Can we get some test results in here? Preferably at least 3 different labs for 1 strain, repeated trials ensure accuracy...

I got a hemp spam email the other day about claimed 17% CBG seeds, minimum order 300k
Some people are going to lose money buying "CBG seeds" this year. There's seed conmen around looking for starry dollar sign eyed hemp farmers that don't know anything about cannabis.

https://oregoncbdseeds.com/compliance/
https://highgradehempseed.com/produc...ory/cbg-seeds/
Soverign Fields has COAs posted on their private instagram account
CanapAromas:

There are definitely bad actors in the hemp seed industry that will sell you canadian bird seed claimed to be high-cannabinoid varieties, whether CBD, CBG, (or THC for marijuana seeds). But that is why I would also like to compile a list of seed vendors. And while I endorse none specifically, I would at least like to list people with authentic seed.

Originally Posted by hellfire

Eventually we should have stabilized F7s and new P1 hemp populations. I would think some CBD breeders are nearing this but due to the market demand for feminized seeds there seems to be a lack of sexual breeding and mostly reversing.

This is one of the points in my first post; To stabilize for a high-CBG ratio only, you would only need to get to F3 lines. Also, not really on subject, but breeding with feminized plants/reversed females is sexual breeding; meiosis occurs, crossing over occurs, there just isn't a Y chromosome involved. All monecious hemp strains are essentially feminized lines with a high enough tendency to hermaphrodite that they will do it without being forced chemically. So, whether using all females with reversals or regular males in a breeding project is irrelevant, other than no hemp farmer in their right mind is planting males in their fields anymore unless they are growing a seed crop.

Originally Posted by hellfire

How low is 'low cannabinoid' on USO 31?

US0-31 is a population that has an allele that prevents cannabinoid production when homozygous; as in undetectable, none, 0 cannabinoids. Read the paper "The inheritance of chemical phenotype in Cannabis sativa L. (IV): cannabinoid-free plants" that I posted a link to.

Originally Posted by hellfire

How many generations does it take to get to 15%+ CBG? It seems to have happened rather quick, at least by these claims. Maybe I'm old hat, skeptical, and think this would take longer than it has.

Total potency is unlinked from cannabinoid ratios. Total potency is a quantitative trait. (Read "A physical and genetic map of Cannabis sativa identifies extensive rearrangements at the THC/CBD acid synthase loci."). When you cross a high- and low- potency variety you will have intermediate progeny. How many generations to get up to 15%+ depends on the starting germplasm. People have been working on this for years. There is some question as to whether all the players worked independently to breed these varieties, or if people are reproducing other people's genetics without permission.

[GrowingHigher]

To follow up: I've grown out some of the Canaparoma CBG. It had 50% germ, and of the 5 plants I grew, one was CBD dominant. The others were all CBG dom. All had a similar habit; that of fiber hemp. Very airy low quality flower.

Kwik Seed Company also now has a CBG variety they claim is only locked for CBG, not morphology. I have not grown this one yet.

[rootfingers]

We plunked down for the minimum required purchase from oregoncbd this year and got a few thousand of their the white cbg strain. So far its incredibly vigorous and resistant to mold and insect pressures. Hasn't started flowering yet but I can check back in with you in a couple months to let you know how it goes. From what I understand the cbg line from them won't run hot and produces just cbg, is that anybody else's understanding as well or am I off?

[socioecologist]

That is correct rootfingers. Nothing to worry about on the compliance side, even on trimmed flowers. F2s or other attempts at breeding with any of our CBG varieties leads to 25% of the plants not passing compliance testing (a forewarning to anyone buying one of the many F2 knock-offs of our limited 2019 release of White CBG).

For anyone interested, the gene responsible for CBG accumulation in our varieties is a defective THCAS allele with a SNP at 1064bp.

[rolandomota]

Waste of time for me have at it

[Reaper]

Originally Posted by rootfingers

We plunked down for the minimum required purchase from oregoncbd this year and got a few thousand of their the white cbg strain. So far its incredibly vigorous and resistant to mold and insect pressures. Hasn't started flowering yet but I can check back in with you in a couple months to let you know how it goes. From what I understand the cbg line from them won't run hot and produces just cbg, is that anybody else's understanding as well or am I off?

I imagine you've havested those by now. How did they turn out

[GrowingHigher]

Dutch Passion now have two varieties (as well as a THC-V variety I wasn't aware of)
CBG-force and auto CBG-force for 15-35 euro/seed claiming ~15%CBG and 1:100 THC:CBG ratios

Hemp Direct is selling something called Desert Snow claiming up to 20% and less than 0.3 (I suspect this is from Oregon CBDs work).

Hoku hemp has a variety of CBG strains, apparently built off European varieties (Italian and swiss).

I have grown the Kwick seed CBG. It was much more resinous than the CannapAroma, but fairly airy, with tall fiber structure. Much more promising, though still only advertised as an 8% CBG plant.



Lastly, this is something that has sort of thrown me through a loop on the CBG breeding theory and I would love if someone could explain it to me: the Whistler Farm's Shiatzu Kush clone that is about 1:1 or 2:1, THC:CBG. I would have thought this ratio shouldn't really exist. So clearly other things that I don't understand yet are happening here.