The effect of ultraviolet radiation on the accumulation of medicinal compounds in plants Wen Jing Zhang a said:"Pate [95] cites older literature suggesting that UV-B radia-
tion promotes cannaboid production in Cannabis and also
speculates about cannaboid evolution. Plots of estimated UV-B
exposure in different growth places shows an increase in Δ9-
tetrahydrocannabinol (Δ9-THC) with exposure, but a decrease
in cannabidiol. Lydon [96] and Lydon et al.[97] found that in
both leaf and floral tissues the concentration of Δ9-THC but not
of other cannabinoids increased linearly with UV-B exposure
in drug-type Cannabis sativa plants, but not in fiber-
type plants of the same species. Nowadays many sites on the
Internet show that the dependency of cannabinol accumula-
tion on UV-B radiation is common knowledge among private
entrepreneurs in the drug industry.
It is not known which enzyme or enzymes for Δ9-
tetrahydrocannabinol biosynthesis are induced or stimulated
by UV-B radiation, but one can speculate. The gene for poly-
ketide synthase catalyzing the synthesis of olivetolic acid
possesses strong sequence homology with chalcone synthase
and may have evolved from this. Chalcone synthase is one of
the classic UV-B-regulated enzymes.
Plots of estimated UV-B
exposure in different growth places shows an increase in Δ9-
tetrahydrocannabinol (Δ9-THC) with exposure, but a decrease
in cannabidiol.
Does this mean that the test subjects where grown outdoors? You cannot isolate UVB as a variable outdoors, and thus cannot assume correlation = causation. Is that entire abstract posted somewhere online? I'd like to read the entire thing.
Awesome pics by the way, that's what I like to see.