Should I add UVB Light?

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Milson

Milson

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Yeah man, the studies are mostly to tempt people into reading the whole paper as interested. Not needed.

I can sum up my hypothesis like this: it seems uvb excites receptors on uvr8, which influences the production of various proteins on the cellular level that lead to a variety of changes. It's plausible this is a mechanism that will increase the production of thc because thc absorbs uvb well and so can serve as "sunscreen."

Using tlc analysis, we can see if we can measure that effect in terms of thc, but also get some insight into how it influences thc (if it does) by looking at the data on other cannabinoids present in a tlc test and applying that to possible scenarios given the pathways observed by scientists for thc production.

I have also noted how these discoveries radically upset the working hypothesis of cannabinoid synthesis in play during much of the seminal research and academic work in the modern history of this plant's study.

Tldr: we are seeing what happens to a plant both chemically and visually when half of it is exposed to uv.
 
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DennisBrown

DennisBrown

Yeah man, the studies are mostly to tempt people into reading the whole paper as interested. Not needed.

I can sum up my hypothesis like this: it seems uvb excites receptors on uvr8, which influences the production of various proteins on the cellular level that lead to a variety of changes. It's plausible this is a mechanism that will increase the production of thc because thc absorbs uvb well and so can serve as "sunscreen."

Using tlc analysis, we can see if we can measure that effect in terms of thc, but also get some insight into how it influences thc (if it does) by looking at the data on other cannabinoids present in a tlc test and applying that to possible scenarios given the pathways observed by scientists for thc production.

I have also noted how these discoveries radically upset the working hypothesis of cannabinoid synthesis in play during much of the seminal research and academic work in the modern history of this plant's study.

Tldr: we are seeing what happens to a plant both chemically and visually when half of it is exposed to uv.
UVC is less effective because UVR8 is most sensitive to high band UVB, so UVC will trigger it, but it takes more, and that is the problem. UVC is very tricky to use. No plants have mechanisms to defend themselves against UVC since it doesn't reach the earth normally. Fortunately, UVC doesn't penetrate very deeply, but most UVC lamps are no-phosphor lamps (256nm) which is very narrow and very intense, so it is difficult to use. Exposure times are in the seconds rather than minutes or hours. It is very easy to overdo it and do damage. Early on (10+ years ago) I had customers who were using UVC and switched to our UVB lamps, so I've talked to probably a dozen people who have tried UVC with mixed results. Yes, it works, but the margin of error is small and it is difficult to use, plus there is the risk of exposure to yourself if you are trying to "wand" the plants. UVB (no matter who you get it from) is easier to work with. The bulbs are also more robust, as UVC lamps are generally quartz, and a small bump can turn them into dust.
 
Moe.Red

Moe.Red

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Well yes.. I mean would you be able to summarize what you are doing?
Day 9 - 2 hours of UV

This is the picture of the control bud, control meaning that it is (hopefully) not being effected by the testing parameter, in this case UVB.
Day 9 Controol Bud.JPG


Those pins are painted with nail polish. Red is control, purple is UV. This was done so that I am sure I am taking photos of the exact same place every day so the comparison is meaningful. In these photos, we are attempting to determine if trichomes "improve" with UV. Improve in this case means larger or more of them as time goes on.

There are 2 pins so we have anchor points that we can use to manipulate the pictures so the size and angle are identical when we match them up later.

And here is the closeup of the same spot with the pin in all the previous day photos:
Day 9 control.JPG


So not only are we counting trichomes, we are studying the effects of UV on the plant overall. For example, in the Day 9 UV bud below, there is little or no growth of the bud threatening to overtake the purple pin. The red pin on the control however is getting swallowed by plant growth. Too early to tell, but I believe that we will find that UV does reduce yield in terms of plant weight, as seen in the differing growth rates UV vs. Control. This was an unexpected result, and I had no intention of using the pins as this sort of data point - happy accident.

Here is the UV bud:
Day 9 UV Bud.JPG


And the closeup:
Day 9 UV.JPG


So now, @Milson will determine if the trichomes are effected with some fancy computer work, but I think it is fine to just compare day 0 to the eventual harvest pic. Those ones need to be perfect, so I'll get my wife to do those since I am photographically challenged lol.

And now for the super close up, lets take a look at a sample from both UV and Control under the microscope.

Right now I have 3 samples each of UV and Control buds in the oven drying out. That is a 2 hour process, and then I will need to decarb at a higher temp for 1 1/2 hours. That needs to be done prior to TLC, so that pushes that TLC result to tomorrow. I will get a video of that process tomorrow and post so you can better understand the test for cannabinoids. The short version is that I have a method to compare ratios of all the important cannabinoids at home so we can determine if in fact THC or anything else changes with the addition of UVB.

Of special interest to yours truly is the CBG in this plant and the changes over time. The plant has to make CBG before it can make THC or CBD, so tracking that along with changes in THC seems interesting.

There are a ton of side benefits to all this as well. As a new grower, taking a look at the color of trichomes and the amounts of cannabinoids at those times can help them to understand the proper times to harvest even if they are not running UV. The whole milky vs amber thing can be explained visually and with data. That is just one of the many side quests happening here. Another is the example of the Purple Kush under UV getting, well, purple and the one only under HPS is still green. There was no expectation we would be looking at that at the beginning of the test, just another happy accident. Anything you can do to impact the plants like that where you have a control and a test along with data can help us to understand other things to, and in many cases just start to understand the right questions to ask.

I'll stop here for now and let you ask some questions (love them BTW). I'm currently uploading a behind the scenes video so you can better understand the process.
 
LaVirtue

LaVirtue

Yeah man, the studies are mostly to tempt people into reading the whole paper as interested. Not needed.

I can sum up my hypothesis like this: it seems uvb excites receptors on uvr8, which influences the production of various proteins on the cellular level that lead to a variety of changes. It's plausible this is a mechanism that will increase the production of thc because thc absorbs uvb well and so can serve as "sunscreen."

Using tlc analysis, we can see if we can measure that effect in terms of thc, but also get some insight into how it influences thc (if it does) by looking at the data on other cannabinoids present in a tlc test and applying that to possible scenarios given the pathways observed by scientists for thc production.

I have also noted how these discoveries radically upset the working hypothesis of cannabinoid synthesis in play during much of the seminal research and academic work in the modern history of this plant's study.

Tldr: we are seeing what happens to a plant both chemically and visually when half of it is exposed to uv.
 
LaVirtue

LaVirtue

Wow this is so interesting - so the UV reduced the yield, but now you are going to analyze it for all the cannabinoids?

As a side note, I decarboxylate our trim and use it for edibles. Why do you decarbox before you test it?

It’s crazy about the colors. I wonder if the sun rays being different around the world makes them come out?

So many interesting things to learn about!
 
Aqua Man

Aqua Man

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Wow this is so interesting - so the UV reduced the yield, but now you are going to analyze it for all the cannabinoids?

As a side note, I decarboxylate our trim and use it for edibles. Why do you decarbox before you test it?

It’s crazy about the colors. I wonder if the sun rays being different around the world makes them come out?

So many interesting things to learn about!
To convert thca into thc
 
Milson

Milson

Milsonian
Supporter
Wow this is so interesting - so the UV reduced the yield, but now you are going to analyze it for all the cannabinoids?

As a side note, I decarboxylate our trim and use it for edibles. Why do you decarbox before you test it?

It’s crazy about the colors. I wonder if the sun rays being different around the world makes them come out?

So many interesting things to learn about!
It's looking like a reduced yield is plausible, but i don't think we can say that for sure.

So you decarb the trim for potency in edibles because thc effect is what you want, not thca, and so you want to convert it completely.

In tlc, it's so the color shows up further up the paper and you can separate them and see the differences. If you don't decarb, all the stuff is still in an acidic form (thca, cbca,cbca, etc) that pools together at the same level so you can't see differences clearly or at all. Thc just happens to have properties so that it wicks further up the paper. So do the other cannabinoids, but at different levels. So decarbing makes the test legible.

@Moe.Red explained this really well on my grow diary. https://www.thcfarmer.com/threads/captains-log-dispatches-from-planet-milson.120787/post-2607698
 
Moe.Red

Moe.Red

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That sound like a good plan. More time to recover in between. Could even do half hour 4 times.
I went ahead and did the 2 hours straight today by popular demand. Time to figure out tomorrow. With no other input I figure I’ll leave it a 2 but open to suggestions

Good news is I can change it at any time from my phone even when I’m not home so I can even decide tomorrow at work.
 
Aqua Man

Aqua Man

Staff member
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Agreed. I will only really be able to add to the anecdote pile because yield in weight is not a controlled test. But I’ll know personally because I can feel it. Just can’t prove it other than a pin disappearing.
Then also the fact that it's plausible the slight reduction in size can be offset by a change in density. Often seen when grown under a more blue leaning spectrum tighter denser buds.
 
growsince79

growsince79

I went ahead and did the 2 hours straight today by popular demand. Time to figure out tomorrow. With no other input I figure I’ll leave it a 2 but open to suggestions

Good news is I can change it at any time from my phone even when I’m not home so I can even decide tomorrow at work.
I'm thinking outside is always changing. Time of day, clouds and other shade... I have a uv that milson linked, but I haven't tried yet because they are pollinated and I don't want to hurt them. Maybe next time...
 
Moe.Red

Moe.Red

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I think "where it pulls from" is a very complex question. I have seen studies that suggest se terpenes may be a precursor to olivolic acid, which starts the chain.
I really think I am losing terps in this process. Plants are still sticky AF, but the overpowering smell is gone.

I really noticed this last night when I opened my oven after decarb. Normally I get a face full of terpenes as the heat leaves the oven and I'm bending over to open it. My head is in the right (wrong) spot to get a good smell of whatever was cooking. I even comment on it in the early videos how strong it was. It's like a blast to the olfactory that is unmistakable.

Last night, meh.

And the smell in the tent is mostly gone. I have to get my nose directly on a bud to smell it.



Clearly not enough info to claim cause and effect, but it is not a small change. If terpenes are your shizzle, UV may not be right for you.
 
MIMedGrower

MIMedGrower

I really think I am losing terps in this process. Plants are still sticky AF, but the overpowering smell is gone.

I really noticed this last night when I opened my oven after decarb. Normally I get a face full of terpenes as the heat leaves the oven and I'm bending over to open it. My head is in the right (wrong) spot to get a good smell of whatever was cooking. I even comment on it in the early videos how strong it was. It's like a blast to the olfactory that is unmistakable.

Last night, meh.

And the smell in the tent is mostly gone. I have to get my nose directly on a bud to smell it.



Clearly not enough info to claim cause and effect, but it is not a small change. If terpenes are your shizzle, UV may not be right for you.

Huh. Interesting. I had not considered nor ever read the effect on terpenes. Flavonoids too I imagine.

I have learned to move the plants away from the light a bit during ripening. Even a couple inches lower from the glass under the 600 hps’ last couple weeks seems to preserve more cannabinoids and terpenes for me.
 
Moe.Red

Moe.Red

Supporter
Huh. Interesting. I had not considered nor ever read the effect on terpenes. Flavonoids too I imagine.

I have learned to move the plants away from the light a bit during ripening. Even a couple inches lower from the glass under the 600 hps’ last couple weeks seems to preserve more cannabinoids and terpenes for me.
It is possible it is unrelated to UV completely. I don't really know, I'm just posting it up as an anomaly I did not really expect. If anything, I would have guessed an increase due to increase in trichomes we are expecting.

Gotta figure out how to do scratch and sniff iPhones so you guys can smell the difference too.

I will say it has not been replaced by another smell like hay or something, it's just missing.

Non-scientific mention:

If this is real and UV diminishes terpenes and as it appears, reduces flower mass, those are 2 pretty big strikes against UV in my book. There have got to be some other benefits to this for UV to be a "success."

Tonight's TLC testing should give some answers. I'm testing 3 UV buds and 3 non-UV buds to try to get an average rather than a single data point (hat tip @Milson ). If cannabinoid proportions have changed between the test and control side, we will see it. If they have not, I will be looking at no upside but significant downside... I think. But it does seem to bring out the purple in Purple Kush... sort of a mixed bag so far.

Today is day 10, we are about 2/3 thru this test. 2 Hours today from 11:00 to 1:00.
 
MIMedGrower

MIMedGrower

It is possible it is unrelated to UV completely. I don't really know, I'm just posting it up as an anomaly I did not really expect. If anything, I would have guessed an increase due to increase in trichomes we are expecting.

Gotta figure out how to do scratch and sniff iPhones so you guys can smell the difference too.

I will say it has not been replaced by another smell like hay or something, it's just missing.

Non-scientific mention:

If this is real and UV diminishes terpenes and as it appears, reduces flower mass, those are 2 pretty big strikes against UV in my book. There have got to be some other benefits to this for UV to be a "success."

Tonight's TLC testing should give some answers. I'm testing 3 UV buds and 3 non-UV buds to try to get an average rather than a single data point (hat tip @Milson ). If cannabinoid proportions have changed between the test and control side, we will see it. If they have not, I will be looking at no upside but significant downside... I think. But it does seem to bring out the purple in Purple Kush... sort of a mixed bag so far.

Today is day 10, we are about 2/3 thru this test. 2 Hours today from 11:00 to 1:00.

for the last 5 years or so I have seen threads mostly with problems caused by the uv tubes and reptile lights. But the growers who figure it out swear by the results.

I guess there is a much steeper learning curve than the product managers tell us.
 
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