UVb an experiment

I totally agree that the pore spacing is genetic, but am still not convinced the UV light is as damaging to plant growth and development as is stated in some responses. After all...for the past 10,000 years cannabis has been subjected to natural sunlight, which has what ammounts to dangerous levels of UV light.
I'm more inclined to believe that a plant has, after all of that time, found a way to either utilize the light to it's benefit, or has developed at the very least a (chemical) tollerance to it, and either way...the results are inside of the trichomes.

What are the trichomes for...?
Trichomes - the source of Magic
Trichomes and you

If indeed the trichomes are a defense against uv light, what does the uv light do to the interaction between the cbc, cbn, cbd and thc? What does lack of UV light do? What does early exposure to UV light do to the plant's metabolism and self-protection habits? (both immediate and long-term) What does restricted-exposure to UV, over many generations, do to the plant's genetics? Is this why some strains react to UV light in flower, and some don't?

A few weeks ago I had a visit from a neighbor's dispensary provider, (a No. Cal. grower) and he had a look at my set-up's. Mentioned I might want a little more ventilation in my flower shed, (was in the high 90's inside the room at the time) and that I should move my UV light from my flower room to my veg room, to accelerate my vegetative growth. He tried very hard to make clear that UV light is more beneficial in veg, than in flower. If it's good enough for a commercial grower with a final product as fine as his...I will be trying it out on my next run.

He was in a hurry, so I didn't get to really pick his brains in-depth. His GPP, TrainWreck and OG Kush are tasty and will make your legs stop working. Been hoping for seeds, but my neighbor has found none in her stock, and I've only seen the guy that one time. :mad:

This is evidence of nothing, but adds another dimension to the topic.

Too late to edit this in, but a while back I came across this:
Chemical ecology of Cannabis


Ultraviolet radiation
Another stress to which plants are subject results from their daily exposure to sunlight. While necessary to sustain photosynthesis, natural light contains biologically destructive ultraviolet radiation. This selective pressure has apparently affected the evolution of certain defenses, among them, a chemical screening functionally analogous to the pigmentation of human skin. A preliminary investigation (Pate 1983) indicated that, in areas of high ultraviolet radiation exposure, the UV-B (280-315 nm) absorption properties of THC may have conferred an evolutionary advantage to Cannabis capable of greater production of this compound from biogenetic precursor CBD. The extent to which this production is also influenced by environmental UV-B induced stress has been experimentally determined by Lydon et al. (1987). Their experiments demonstrate that under conditions of high UV-B exposure, drug-type Cannabis produces significantly greater quantities of THC. They have also demonstrated the chemical lability of CBD upon exposure to UV-B (Lydon and Teramura 1987), in contrast to the stability of THC and CBC. However, studies by Brenneisen (1984) have shown only a minor difference in UV-B absorption between THC and CBD, and the absorptive properties of CBC proved considerably greater than either. Perhaps the relationship between the cannabinoids and UV-B is not so direct as first supposed. Two other explanations must now be considered. Even if CBD absorbs on par with THC, in areas of high ambient UV-B, the former compound may be more rapidly degraded. This could lower the availability of CBD present or render it the less energetically efficient compound to produce by the plant. Alternatively, the greater UV-B absorbency of CBC compared to THC and the relative stability of CBC compared to CBD might nominate this compound as the protective screening substance. The presence of large amounts of THC would then have to be explained as merely an accumulated storage compound at the end of the enzyme-mediated cannabinoid pathway. However, further work is required to resolve the fact that Lydon's (1985) experiments did not show a commensurate increase in CBC production with increased UV-B exposure.

This CBC pigmentation hypothesis would imply the development of an alternative to the accepted biochemical pathway from CBG to THC via CBD. Until 1973 (Turner and Hadley 1973), separation of CBD and CBC by gas chromatography was difficult to accomplish, so that many peaks identified as CBD in the preceding literature may in fact have been CBC. Indeed, it has been noted (De Faubert Maunder 1970) and corroborated by GC/MS (Turner and Hadley 1973) that some tropical drug strains of Cannabis do not contain any CBD at all, yet have an abundance of THC. This phenomenon has not been observed for northern temperate varieties of Cannabis. Absence of CBD has led some authors (De Faubert Maunder 1970, Turner and Hadley 1973) to speculate that another biogenetic route to THC is involved. Facts scattered through the literature do indeed indicate a possible alternative. Holley et al. (1975) have shown that Mississippi-grown plants contain a considerable content of CBC, often in excess of the CBD present. In some examples, either CBD or CBC was absent, but in no case were plants devoid of both. Their analysis of material grown in Mexico and Costa Rica served to accentuate this trend. Only one example actually grown in their respective countries revealed the presence of any CBD, although appreciable quantities of CBC were found. The reverse seemed true as well. Seed from Mexican material devoid of CBD was planted in Mississippi and produced plants containing CBD.

Could CBC be involved in an alternate biogenetic route to THC? Yagen and Mechoulam (1969) have synthesized THC (albeit in low yield) directly from CBC. The method used was similar to the acid catalyzed cyclization of CBD to THC (Gaoni and Mechoulam 1966). Reaction by-products included cannabicyclol, delta-8-THC and delta-4,8-iso-THC, all products which have been found in analyses of Cannabis (e.g., Novotny et al. 1976). Finally, radioisotope tracer studies (Shoyama et al. 1975) have uncovered the intriguing fact that radiolabeled CBG fed to a very low THC-producing strain of Cannabis is found as CBD, but when fed to high THC-producing plants, appeared only as CBC and THC. Labeled CBD fed to a Mexican example of these latter plants likewise appeared as THC. Unfortunately, radiolabeled CBC was not fed to their plants, apparently in the belief that CBC branched off the biogenetic pathway at CBD and dead ended. Their research indicated that incorporation of labeled CBG into CBD or CBC was age dependent. Vogelman et al. (1988) likewise report that the developmental stage of seedlings, as well as their exposure to light, affects the occurrence of CBG, CBC or THC in Mexican Cannabis. No CBD was reported.

Good to see ya R.T.

2 great post in a row!
Mahalo nui!
I owe ya one brah.
Dis bud's for you. :jointsmile:

Aloha,
Weezard

subscribed! now i have to go back through and read it all!


-shake

when y'all reach a conclusion...call me...:D

Hey Weezard,

Thanks for clearing up the confusion I had about the leaf CELLS turning on edge. I really thought you where trying to tell me the leaf edges were turning thier edges to the light, and I really did not see how that was possible. The thykaloid disk packs makes sooo much more sense now. Thanks for that.

I found reference in a Rutgers' paper to an increase in "green leafy plant material" due in part to high levels of light activivity or "increases of UVb light", mentioned in a paper dealing with CO2 utilization.

Yo Rusty,

Big thanks for the posts, there is little doubt in my mind that trichomes are where the magic happens and are not designed as plant defense mechanisms, but are in fact designed to collect and condense light (specifically UVb) and act as cellular factories to produce THC.

Your friends idea of using UVb during veggative growth is most interesting of all from a usefullness angle. It makes sense that since the cannabiniods or at least thier percursors all start off during the veggative stage, UVb may play a role earlier in the plants developement then I had thought. I need to do some more reading (right here even to start) and digest this some more.

Quote:

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Originally Posted by headshake

subscribed! now i have to go back through and read it all!

-shake

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Hey Shake,

This isn't so bad to read thru, at least this thread is young enough that I haven't gotten the chance to go too off topic.....yet.
Opens up the interesting area of internal reactions of the plant, at a cellular level.

Hello Pimp,

We will certianly let you know the out come when we reach some sort of conclusion. :D

I've got some clones rooting, so hopefully I'll be able to do a sort-of side by side. (top and bottom) Will have to remove some bulbs from bottom (late veg) space to make 'em even-stephen, but if Farmer Bob's advice is correct, I might not miss the missing lumens.

Kinda off-topic...but this is my latest veg closet. Half clothes, half growroom.

The drip trays are lined with aquarium gravel, so I don't need drainage rocks taking up room in the pots, and makes transplanting a breeze. Clone tray cover is a sheet of plexiglass. Holds 12 clones. The plastic tray and bulb bases (outdoor security lights) are both from WalMart, UV light is in the bottom section. The shade cloth keeps the light from glaring off my computer screen. (and no signs of the bulbs melting it at all) Has an unlighted upper level (not shown) for a tub of just-planted seeds. (versatility)

Anyway, I guess we'll see how it goes. :jointsmile:

I find this fascinating. LED and advanced light technology have always come off to me as an intimidating read. I feel like I wouldn't know where to start reading to understand it all. Perhaps Weezard can point me in the right direction of a thread or something that would be a friendly read for an LED noob. I'm obviously not a plant idioit, as it is my major of study, I just have not had the light experience...

Thanks to all, I'll be keeping up with this one

SMG

Kind of on topic.

Got some new snaps of led grown buds.
[attachment=o224636]

[attachment=o224637]

[attachment=o224638]

All UVb free from birth.
First taste indicates presence of active ingredient.:D

Aloha,
Weeze.