Airwalker16
Well-Known Member
I'm with you 100% on everything you mentioned.
Adding UVB spectrum to COBs - opinions on this setup?
Airwalker16
Well-Known Member
P.s. hoe many bags do you use for bubble? I'm gonna buy a set cause I got a shit ton of trim and larf I GOTTA do something with.
researching
Well-Known Member
I just do 4 including working bag. 220,120,73,45. Sometimes I will use a 25 as well. Typically 45 and smaller is edibles.
Airwalker16
Well-Known Member
25 is the primo shit I thought.
PhotonFUD
Well-Known Member
So what did you get from that ? I only read the conclusion that it seemed to increase thc in "Drug" plants ?
lolsorry I had to laff with "Drug" plants reference
Actually it says that there was a measurable increase however they couldn't associate the increase as a correlation to the added uv-b light. It wasn't the focus of the study which is why that finding was left equivocal.
The study was to see if there was an impact on cannabinoid production by the availability of uv-b light as it was believed that cannabinoids readily absorb uv wavelengths. Results did not show an increase in cannabinoid production and therefore the study concluded that uv-b availability didn't affect cannabinoid production.
The increase is more likely explained as the plant responding to environmental stressors. A study to determine the effect of uv-b wavelengths on plant stress is what is needed to properly answer the question.
On another note, uv light is good for other reasons - eg. pest control. If short amounts of uv light do not harm the plant then that could be used as another tool for gardeners in the war on pests.
Uberknot
Well-Known Member
I would like to see more studies on loss of plant weight (damage) vs amount of UVB used and increase in THC %.
Does the loss directly correlate with the amount of UVB used and is the THC % gain more or less compared to the loss?
It will be interesting over time to see some scientific studies.
Does the loss directly correlate with the amount of UVB used and is the THC % gain more or less compared to the loss?
It will be interesting over time to see some scientific studies.
Huh? The study seemed to directly correlate added UVB to increases in THC production.
Sassafras¥
Well-Known Member
I did a little test a few years back myself on this. I took one of the uvb reptile bulbs linked here http://www.google.com/aclk?sa=l&ai=DChcSEwijmp-qjvvOAhWIPYEKHUktA4wYABAN&sig=AOD64_0Z6o6AlEAxRs-qLe2LXgfn6MaDQQ&ctype=5&ved=0ahUKEwi1yZyqjvvOAhUFQSYKHbJcDGgQwg8IJg&adurl= and simply ran it a few hours a day over one of two of the same cuts of a strain at the time I had a mother of. I have to say on the plant that received the added uvb vs the plant that didnt, I could see a slight increase in trichome production to say the least. Wished I had it documented, however back then I didn't take pictures or notes of any kind.
researching
Well-Known Member
You got the shit part right. 120-73 is where its at. Full melt love.
Uberknot
Well-Known Member
I wonder if the increase in trichomes is related at all to the damaged tissues and some kind of mutation or repair?
Sassafras¥
Well-Known Member
I really don't know, I would have to do more tests on this subject to give an accurate asumption. However like said it was a notable difference in the two that's for sure.
PhotonFUD
Well-Known Member
No, in the summary it stated that the finding was equivocal, as in they weren't able to explain whether that observation was the result of uv-b availability or some other factors.
Research cliffhanger/opportunity for a sequel
Uberknot
Well-Known Member
It almost seems like the trichome increase is in part to protect the plant from UV.
Plant gets damaged....plant make more of protection..
I used a 2' AgroMax Pure UV last run, 36" from canopy (top of tent). I did four 30 minute intervals each day. Not terribly conclusive, but my Malawi that came out is pleasantly potent!
I'll def use again, I actually designed my cob frame to be as open as possible to allow UV bulb to sit top center..
I'll def use again, I actually designed my cob frame to be as open as possible to allow UV bulb to sit top center..
Fastslappy
Well-Known Member
what size is yer tent ?
PhotonFUD
Well-Known Member
Did you have any pest issues?
3 x 3
thankfully never any pest issues, in a tucked away closet though.
" In conclusion, the A9-THC content in leaf and floral tissues of greenhouse grown drug-type C. saliva increased linearly with UV-B dose. Other cannabinoids in drug- and fiber-type plants were unaffected by UV-B radiation. Both drug and fiber chemotypes were physiologically and morphologically tolerant to UV-B radiation. Thus, this tolerance was observed regardless of the concentration or composition of UV-B absorbing cannabinoids. Therefore, it appears that other factors may contribute to the UV-B insensitivity of vegetative C. sativa. Nevertheless, the increased production of A’-THC in floral tissues (where this compound is most concentrated) of drug-type plants upon UV-B irradiation may result in more reproductive success for drug-type than fiber-type C. sativa in high UVB environments as suggested by Pate (1983)."No, in the summary it stated that the finding was equivocal, as in they weren't able to explain whether that observation was the result of uv-b availability or some other factors.
Research cliffhanger/opportunity for a sequel
The fact is, we dont really care about the fiber based plant type or its reactions at all. I agree more research is needed, but in this case, for the parameters we are concerned with, these results seem promising.
something like that ? http://medicalmarijuanagrowing.blogspot.it/2013/02/uvb-uva-lighting-study-results.html
there's an old but better done scientific study with similar conclusions
https://silassativariusdotorg2.files.wordpress.com/2016/01/uvb-effects-on-photosynthesis-growth-and-cannabinoid-produciton-in-cannabis-sativa.pdf
sorry if I exhume old post and if I'm giving redundant information