I’m asking because I found a very strange article, which goes against what I’ve learned with Bruce Bugbee (who has some videos talking about UV, if you want I can put the links) and also against what I learned with Shane from Migro Light.
I’m even testing a 24W UV lamp here for just 15 minutes and I had good results, the plants resined well and stayed fine until the end of their life.
I thought the article itself had some flaws:
-very high UVB intensity or for a long duration
13.4kJ per day, 3.5 hours per day
but I ended up discovering that it was the same intensity in another study that for strange reasons found positive results.
This left me a little confused, as I thought this was the cause of the error.
-little sampling number
-little diversity (there were only two genetics)
and as far as I know, the amount of UVB that the plant can handle can vary with the cultivar (or not?)
Because the amount of UV that the plant receives varies according to geographic location, so I imagine that some strains are more resistant than others?
-Appearance of powdery mildew on the adaxial sides of the leaves
Shouldn’t UV prevent this?
Does this scientific study make sense? Can it be trusted? What do you think ? Anyone interested is very welcome to refute anything I’ve said, I love to learn, let’s discuss about =)
and then Breaking Wave is a 1:1 version of Low Tide with supposedly high varin cannibinoids as well?
I will read the full article today if I get a chance, it’s always interesting to see this UV research advancing, and I’ll be curious to see their methodology and results. I’ve been using Solacure Super B tubes since I started growing, from mid veg onward so far as directed by Solacure and Dr Bruce, but I was considering leaving them out this round, or at least trying just the last few weeks instead. I moved my setup and when setting back up I left out the fluoro fixtures until I got everything else sorted, which has meant no UV until now at the earliest (three weeks into flower).
Was typing a response when I realized we came to the same conclusion, bad “study” or “trial” in my opinion, but that’s not speaking to/about the science at all, just their protocols were junk.
The second paper you posted was from 1986 so as far as how accurate the science is I’d lean more towards the first, but at the same time there is an extreme amount of mis information on the web. I’d say if you see a difference when using the uv light then keep doing what your doing. First hand observation and experience is the most reliable way to get information
Me too. Solacure has another good texts about UV but nothing ‘‘scientific’’ I think. Just some very old papers too
I think this is most likely. Did you see anything else wrongfully done ?
Thats true.I think I still used this article even though I knew it was old, but mostly because I hadn’t noticed HOW old it is, 1986 doesn’t seem that far back hahahaha.
I think if someone used some article that old to argue something with me, I wouldn’t think it would be a strong argument.
I just looked at the Solacure site and they’ve actually taken down their research page because they felt it was out of date. I get the impression they will be putting it back up some time at the point at which they can collect and present the research they’ve got.
Being a homegrower, I’m very tempted to invest in some UV. The fixtures don’t cost much and the benefits could be great. I know the jury is still out on which cultivars benefit from the addition and the best ways to apply it, but it’s fun to mess around;)
Reading through these though I’m thinking I need to better time my UV lighting, it runs 12 hours right now and I’m thinking it should only be like 4-6 hours right in the middle to simulate high noon and what not vs 100% UV blasting for entire light cycle, might even be hurting them with what I’ve got it set at.
And @space I think their science is pretty solid aside from the ridiculously small experiment size.
Why wouldn’t they have spread out all the plants they used to keep canopy level even and had each under different UV lighting sources instead of one brand of LED diode and many wavelengths of UV in the spectrum so they had a giant group to test with many different controls vs just the results of two plants and one brand of one wavelength of led diode
Idk, all they proved was those specific UV diodes didn’t do much on those plants essentially
Additional graphs related to terpenes in the above reference PDF.
Several of these graphs details a statistically significant result (the graphs with trend lines) where there is an increase (positive correlation) in decarboxylated cannabinoid content for the breaking wave cultivar while the low-tide cultivar indicates a negative correlation.
Supplementary Figures 1–12. In LT, the concentrations of 19-
THCA, CBDA and CBGA decreased linearly by 15%, 21%, and
31%, respectively, as UV-PFD increased from lowest to highest;
with concomitant reductions in 19-THCeq, CBDeq, and CBGeq.
As UV-PFD increased from lowest to highest, the concentrations
of myrcene, limonene, fenchol all decreased in LT, resulting in a
combined 41% decrease in the total terpene content. In BW, the
19-THC concentration was 1.6 times higher and the ratio of 19-
THCeq to CBDeq was 10% higher under the highest vs. lowest
UV-PFD. The myrcene and linalool concentrations decreased
while caryophyllene and guaiol concentrations increased with
increasing UV-PFD, resulting in a combined 24% decrease in the
total terpene content in BW at the highest vs. lowest UV-PFD.
For breaking wave, no correlation in the THCA content but a positive correlation in the d9-THC (that seems to make sense). For low-tide, negative correlation in THCA but no change in d9-THC (odd). The d9-THC equivalence shows no change for low-tide but a modest positive correlation in breaking-wave.
It does seem that they were targeting UVR8 (280-315 nm). The measured spectrum seems covers that range. They do mention that perhaps different wavelengths may have different results but I didn’t see any mention of utilizing additional cultivars in a trial … since the UVR8 pathway leads to gene expression … which you’d think they’d key on based on the differences noted between the two they had utilized.
I’m thinking this study as a data point, not necessarily conclusive. Have to study this one in more detail. A different design of experiment may lead to different results as you’ve noted.
According to the video and the part that bruce is talking to then the conclusion is that theoretically the UV should increase the cannabinoids, but they still haven’t been able to define the correct spectrum, the correct dose and the correct duration.
@anon85454369 where are the guys research papers on cannabis? You Google his research and nothing cannabis related comes up except videos and threads in RIU or reddit, could you link me to some actual research papers vs a VIDEO? (Insane to me people take videos as actual science and facts…)
I understand he’s a scientist and understands light but he doesn’t give a shit about cannabis, it gets him likes and views and money and an industry to actually use his lighting instruments in
Edit; ok I did find info on his Apogee instrument website and they started their work in may of last year. So in one year they’ve definitively found UV has no positive effect on any cannabis plants even though they’re only testing two low THC high CBD cultivars? Sounds almost exactly like the first post in this thread…
That’s the same publicity article I was finding on other websites just stating they were going to be starting the research cause things changed. Maybe I’m wrong and he is genuinely passionate about the plants but I’m always apprehensive about new information and check and double check before I start to consider something as possible fact, I’d love to read his research papers when the time comes.
Really sucks that your every day person can’t converse and object or confirm with these researchers, a lot of us growers have put in much more time testing these theories than he has, wouldn’t we be good information for research?
“Believe nothing of what you hear and only half of what you see” and all that
I saw some videos of bruce and Shane from migro and from what I saw them talking about researching with UV is expensive, as measuring equipment is more expensive and UV LEDs themselves are also expensive and inefficient, which makes research difficult.
The tricky thing for me about UV is that even for home growers it’s hard to say that UV ‘improved’ the cultivation, even old research that ‘‘proves’’ UV is beneficial says it improves cannabinoid levels by 5 to 15%, which visually it is difficult to measure and can even be a factor with a placebo effect
I used it in a few cycles and I didn’t see detrimental results and I wouldn’t be able to confirm if UV is being something differential for me either, but in fact the plants are producing trichomes very well, now it may be that they would already produce high levels of trichomes exactly the same without the UV hahahaha
I will continue testing because I already have the light
