This is not mine, do not give me credit.*** But here is some info on uvb lights. Maybe this will help.
“ive read a bunch on how plants grown outside is stronger than the same strain grown indoors. and how UV rays are what cause this. UVB are mostly responsible as they are the stronger of the UVB rays. UVB is what you get sunburns/tans from. the plant makes resin to fight off the UV rays, so outside makes for stronger pot.
assumeing all that is right, if you added a UVB light source to a grow room where it would just come on for alil while each day of the flowering phase you might be able to get stronger buds indoors. and if that did work whos to say by makeing the light stay on alil longer each day than the day before the plant wouldnt just go crazy and turn into a huge pile of THC??? lol
anywhoo, what do ya’ll think? worth a shot or not?”
……possibly the most authoritative piece that I have found so far is Pate, D.W., 1994. Chemical ecology of Cannabis. Journal of the International Hemp Association 2: 29, 32-37. This paper is widely referenced in future documentation…so just as I do in my professional work….I like to stick with what the ganja research fraternity takes as somewhat of an authoritative piece.
As a little of an aside, this may be valuable in the discussion relating to the “purpose” of resin – in regards to this, it references anti-dessication (i.e., THC concentration higher in xeric conditions), antimicrobial, antifungal, antifeedant *i.e., chemical and physical deterrent) and UV-B pigmentation roles. But that’s another topic. I want to look at what factors might best guide us in further maximizing our resin production and thereby potentially, our potency.
In this regard, I take from this paper (and the unavoidable tangential research….), the following:
cannabinoids are present in glands throughout the plant in two forms…stalked and not stalked;
the density of glands increases as you move up the plant (uncertain whether or not this is a function of maturity or structural difference – more study needed)
in one study, the THC generally increased as locations became less favorable for plant growth, suggesting increased plant stress enhanced delta-9-THC production
cannabinoids also may function in the role of UVB protection (another biological stress-inducer), which may be functionally analogous to human skin pigmentation (again more study needed to understand and resolve current information).
colour rendering Index (CRI) with a maximum value of 100 (i.e., that of outdoor daylight) – only comparable with lights on the same temperature (i.e., 2700K, or 6500K, etc.). For example it is un-instructive to compare identical wattage CRI (70 vs. 20) of MH (4500K) vs. HPS (2700K)
recent developments in LPS (Low pressure sodium) might provide some better solutions
Pate (1983) and Lydon et al (1987) both demonstrated that under conditions of high UV-B exposure, drug-type Cannabis produces significantly greater quantities of THC.
The following are a couple of excerpts from a post entitled UV and it’s effects (BC Growers Association)….from 1999…..
hXXp://www.geocities.com/SunsetStrip/amphitheatre/5796/uv.htm
“Growers use two or more 20 minute UV light treatments during the day cycle.”
“Metal halide produce the best potent weed less lumens for the money but better smoke. After years of testing with some friends who did want to keep THEIR recipe (more hps) i foung there weed to be harsh, full of CBD, make me eat and sleep, only good to sell to someone else taht you dislike. The blue spectrum will give you a final product that have everything included :taste without curing, potency and yield, To be effective a ratio of 2 MH for 1 hps at the most.(hps) Hps alone can produce a cash crop but not a connaisseur crop.
Et Voila...”
Q1. if UV in ionisers is used for odour control, will high UV light conditions (high altitudes) also influence odour – which has been postulated to have important functionality in the life cycle of cannabis?
Q2. should/could we maybe consider the introduction of a “highly limited” level of exposure to UVB to enhance resin production while within the limited of phytological degradation?
Q3. do we need to take a closer look at the true comparison of the growth potential/potency of using HPS vs. MH vs. MV lights? Have we been incurring a limitation to potency by using HPS lighting for flowering?
eace:
