ClosetGarden
Active Member
It’s been well established cannabis plants produce more THC in response to UV light as a protective agent. My question is, does this mean CBD levels are lowered due to the plant’s focus on THC production?
UV and CBD
- Thread starter ClosetGarden
- Start date
doug mirabelli
Well-Known Member
Wish I knew. How can we incorporate UVlight indoors?
ClosetGarden
Active Member
There are T-5 bulbs that emit UV-B light. I would use it sparingly.
https://www.htgsupply.com/products/agromax-pure-uv-t5-bulb-2-foot
https://www.htgsupply.com/products/agromax-pure-uv-t5-bulb-2-foot
medicated18408
Member
Here's an excerpt from an article from high times:
"Plants grown above the 30th Parallel North typically have higher levels of CBD relative to THC, and plants originating from between the 30th parallel north and the 30th parallel south have higher levels of THC with little to no CBD. The first encounter with a South African strain that had high levels of THC with not a trace of CBD in 1973 reinforced this theory given the high natural UVB light intensity in the area."
Here's a link
https://hightimes.com/grow/grow-hack-does-uv-light-increase-cannabis-potency/
"Plants grown above the 30th Parallel North typically have higher levels of CBD relative to THC, and plants originating from between the 30th parallel north and the 30th parallel south have higher levels of THC with little to no CBD. The first encounter with a South African strain that had high levels of THC with not a trace of CBD in 1973 reinforced this theory given the high natural UVB light intensity in the area."
Here's a link
https://hightimes.com/grow/grow-hack-does-uv-light-increase-cannabis-potency/
SPLFreak808
Well-Known Member
The added UV would likely speed up the trichomes oxidation process, pretty much why plants grown in equatorial/elevated areas are insanely strong regardless of yield.
Cannabinoid synthesis in marijuana plants starts with the production of cannabigerolic acid or CBGA – the acid form of CBG, whose formula is C22H32O4 – in the trichome heads from the combination between olivetolic acid (and/or divarinic acid) and geranyl pyroshosphate (the combination with divarinic acid produces cannabigevarolic acid or CBGVA). After a series of reactions caused by the production of specific synthases (enzymes)- which are named depending on the cannabinoid they produce – CBGA is transformed into the acid form of the three main cannabinoids:
Normally, hemp strains contain more CBG than narcotic cannabis varieties. According to studies, this could be caused by a recessive gene which inhibits the production of some of the aforementioned synthases, so that most CBG produced will not be transformed into other cannabinoids by these enzymes.
Its seems mainly genetics, the right harvest time & the recessive traits from hemp.
https://www.alchimiaweb.com/blogen/cannabigerol-cbg/
Cannabinoid synthesis in marijuana plants starts with the production of cannabigerolic acid or CBGA – the acid form of CBG, whose formula is C22H32O4 – in the trichome heads from the combination between olivetolic acid (and/or divarinic acid) and geranyl pyroshosphate (the combination with divarinic acid produces cannabigevarolic acid or CBGVA). After a series of reactions caused by the production of specific synthases (enzymes)- which are named depending on the cannabinoid they produce – CBGA is transformed into the acid form of the three main cannabinoids:
- THCA or tetrahydrocannabinolic acid, which is produced from enzyme THCA-synthase
- CBDA or cannabidiolic acid, produced by the action of enzyme CBDA-synthase
- CBCA or cannabichromenic acid, which is produced by enzyme CBCA-synthase
Normally, hemp strains contain more CBG than narcotic cannabis varieties. According to studies, this could be caused by a recessive gene which inhibits the production of some of the aforementioned synthases, so that most CBG produced will not be transformed into other cannabinoids by these enzymes.
Its seems mainly genetics, the right harvest time & the recessive traits from hemp.
https://www.alchimiaweb.com/blogen/cannabigerol-cbg/
The resin production is increased to protect the flower from UV damage. The amount of THC or CBD would be determined by the amount of THCA synthase and CBDA synthase coded for in the plants DNA- , not the UV light. If you had a high CBD hemp plant you were growing for flower under increased amounts of UV it would display increased resin which, presumably, would be higher in CBD, or really CBDA. That plant would still have low THC but it might be higher than it would have if it weren't exposed to the increased UV. I think the high THC plant would be similar. It would probably have a slight increase in both cannabinoids.
mr. childs
Well-Known Member
that study is from 1986, i wish i could see what the same research department is working on today.
PhenoMenal
Well-Known Member
the reason you can only increase by small amounts is because the cannabinoid profile is genetic ... stop bothering to find ways to increase CBD by 0.1% by lights or whatever, try to find better genetics
LinguaPeel
Well-Known Member
Uv doesn't increase thc, just makes trichs pop.
SMT69
Well-Known Member
my thinking is , the end result, would be yes.
(it may be that it produces more trichomes(quantity), which in essence, would have a direct result in the final (more) total thc % of the flower) no ?
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T macc
Well-Known Member
Its UVA that increase thrich coverage. UVB to make them more potent.
Porky101
Well-Known Member
All UV light is used in photosynthesis. UV light is never wasted. just dont use too much.
T macc
Well-Known Member
Right. But different nanometers of light have different effects on photosynthesis.
And yes, CMH is liked for its UVA production.
Porky101
Well-Known Member
Yes.
The point I was making is, until recently UV was not recognised as a type of PAR. Only recently has science "admitted" that UV radiation is indeed PAR radiation (The plant uses it to GROW). UV is not simply additional light to achieve a bit more trichomes, it counts as PAR.
T macc
Well-Known Member
Gotcha. Yea, a bit tighter mode spacing, I notice more trichomes in veg now. Even a week from seed. I'm sure it makes the plants hungry for more nutrients?
Porky101
Well-Known Member
Definitely. The plants aren't really hungry. That's a human word. Of you give them more energy, they can do more with the nutrients, so faster growth etc. Uv is a very high energy light, so it actually penetrates the leaves and stems and buds.