Yeah its like the last piece of the puzzle that kinda puts so many things in order for me.I thought this segment was interesting from the paper:
Cannabis plants grown under blue light with a short photoperiod (12 h light:12 h dark/flowering stage) improved cannabinoid content (Magagnini et al., 2018). This same study suggested that there is a synergy between UV-A and blue wavelengths that induces cannabigerol accumulation in cannabis flowers.
My personal testing bears this out.
A low percentage (≤ 24%) of green light enhanced plant growth, whereas plant growth was inhibited under a higher percentage of green light
I find interesting. Taken together, these 2 studies say that green at high PPFD promotes the highest CO2 consumption, and therefore photosynthesis, however when you supply more than 25% green you actually stunt the plant.
My takeaway is that highest possible photosynthesis is not our goal when growing cannabis, if large cannabinoid rich plants is what you are after.
I wish @Milson was still around, he was always able to cut thru the chaff on these kinds of papers and pull out the nuggets important to us growers.
You mention that HPS>MH above, I think perhaps that generalization does not hold 100%. I run Eye Hortilux bulbs with this spectrum in my non-LED tents, and after more than a dozen grows, I find this bulb / spectrum outperforms all others in terms of size and cannabinoid profiles.
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I'm starting to see why that might be. Your original paper also discussed Orange - this bulb has a lot more green and orange than most of the other light sources out there.