UV Light and Terpenoids

[Telegraphist.]

How do you rate the repti glo bulbs Indi? I have a photometer so will get busy tomorrow and take some reading with the repti glo's at various distances and post the results

I am using 3 just now to cover a thin band about aprox 1metre x 20 cm, with 1 250 watt CFL to add blue spectrum. I also use HPS or MH (last week or two)
Not had enough time/ experience with using the extra lights to tell any difference yet but will keep you all posted

Anybody used a blue filter over a MH light? Would the better PAR values be ruled out by the filter attenuating lumens?

Good luck with the experiments and please cover eyes and take precautions with UVB. You know the risks but anyone else experimenting please cover up all exposed flesh and never look directly at the light without eye protection. UVB DAMAGES DNA

 

[indifferent]

You can get UVB LEDs but they are very expensive speciality items from niche manufacturers like Marubeni and Roitherner.

I am using the 26W 10.0 UVB Reptiglo and I think it's an interesting lamp. After some reasearch, I found out what the 10.0 UVB figure actually means, it's 10% of the UVB levels at the equator at noon.

The problem with assessing this bulb is that it has a broad output and has a load of deep blue as well as the UVA and the little bit of UVB.

UVA has been shown to have an effect on the production of flavinoids and terpenoids, deep blue light stimulates the carotenoid terpenoids like beta-carotene.

The type of UVB needed for THC stimulation is in the 290-300nm range and the reptiglo just doesn't have enough UVB imho.

I think for UVB, we are limited to three practical choices:

1. A philips TL-01 UV lamp, these are narrowband UV lamps with the peak output at 311nm, used for psoriasis treatments. Hard to find the bulbs and the 40W 2 footer is about 50 ukp, they do a 9 watt pl-2 CFL type too but not found that one anywhere for sale.

2. An Osram Vitalux 300W self ballasted mercury vapour lamp, these have a massive UVB and UVA output and are ideal for larger grows. Deoending on where you buy one, they cost between 35 and 50ukp and need to be fitted in a ceramic e27 socket, they generate a lot of infrared and heat too.

3. A 100w or 160w self ballasted mercury vapour lamp, there are several brands of these for sale, they are sold as reptile UV basking lamps, they are a smaller version of the Vitalux.

There are lots of cheap UVA tubes on ebay these days, you can buy a pack of four 9W PL-S CFL UV lamps for 5ukp, they are intended for acrylic nail art curing and are basically blacklights with a peak at 365nm so they are useful for UVA but have virtually no UVB.

Also widely available now are the UV-C germicidal lamps, these are available in all kinds of sizes and shapes and are pretty cheap. They are nothing more than a fluorescent lamp without a phosphor coating and emit a spike of UVC centred at 254.7nm which is no good for THC stimulation and will just damage the plants.

One use for UVC tubes in the grow room though, and I'm going to get a couple of 9 watters to try this out is pest and disease control. UVC kills pests like thrips, mites and gnats and destroys mildew and moulds. I will have to read up on what exposure lengths and dosages should be used, perhaps 15 mins a day will be enough, it is UVC which fucks with DNA and it is highly hazardous, you need to setup a switch to turn off any UV lights before entering your grow whether UVA, UVB or UVC.

I bought a pair of UV protective ski goggles on ebay for 4.99, not for protecting me against the UVC and UVB I will be using, i will make sure I'm nowehre near those lamps when they are on, but so i can work on my grow without turning off the UVA tubes. Anyone who is gonna mess with UV, get yourself a pair, it's much cheaper than a new pair of eyes!

PS two of the carotenoid terpenoids have UVB blocking properties and are found in the human retina where they serve as UV protection, they are also found in cannabis and are stimulated by UVA/violet light in the 380-440 range.

 

[B. Friendly]

http://www.exo-terra.com/en/products/compact_fluorescent_bulbs.php I use these and yes they add crystal production!!!

http://www.greenmanspage.com/guides/thc.html
Home Page:
http://www.greenmanspage.com/guides/

An elaboration on the phytochemical process that makes marijuana THC
The resin exuded by the glandular trichome forms a sphere that encases the head cells.

When the resin spheres are separated from the dried plant material by electrostatic attraction and placed on a microscope slide illuminated with a 100W incandescent bulb, they appear very dark when observed through a 300X microscope. Since orange, red, and infrared are the component wavelengths of incandescent light, and since the absorption of light makes an object dark or opaque to the frequency of the incoming wave, one can conclude that these wavelengths are probably not directly involved in energizing the cannabinoid pathway.

However, the resin sphere is transparent to ultraviolet radiation.

The author found through trial and error that only one glandular
trichome exhibits the phytochemical process that will produce the amount of THC associated with pain relief, appetite stimulation and anti-nausea; euphoria and hallucinations are side-effects, however. This trichome is triggered into growth by either of the two ways that the floral bract is turned into fruit.

Of all the ways that optics are involved in the phytochemical production of THC, the most interesting has to be how the head cells and cannabinoid molecules are tremendously magnified by the resin sphere. These and other facts are curiously absent from the literature. The footnotes update the literature to include electrostatic separation of the resin sphere from the dried plant material and marijuana parthenocarpy.


(1) "For all spheres, a ray drawn perpendicular to the sphere's surface will intersect the center of the sphere, no matter what spot on the surface is picked, and the magnifying power(a) of a glass sphere is greater the smaller its size. A sphere of glass can also bring light that is heading to a focus behind it to a point within it, with freedom from two aberrations, spherial aberration and coma, but not from chromatic aberration. Chromatic aberration results when different wavelengths are focused on different planes and is the most difficult of the aberrations to correct. The human eye lens also exhibits chromatic aberration, but a yellow pigment(b) called the macula lutea in the fovea, an area at the rear of the eyeball, corrects this problem by the way it absorbs blue light."

(a)"The formula to calculate the magnifying power of a sphere is l=333/d, where l is the magnifying power and d is the diameter of the sphere expressed in mm."

(b)Interestingly, the resin exuded by drug-type flowering female marijuana plants has a yellow tint. Could this pigment work to correct chromatic aberration in the resin sphere like the macula lutea does in the fovea for the eyeball?

(2) Quoting from the Mahlberg and Kim study of hemp(a) "THC accumulated in abundance in the secretory cavity where it was associated with the following: cell walls, surface feature of secretory vesicles, fibrillar material released from disc cell wall, and cuticle. It was not associated with the content of the secretory vesicles."

The resin spheres contain the THC. It is not contained in the leaf or floral bract. After the resin spheres are dissolved in solvent or dislodged by electrostatic attraction, and a microscopic examination of the leaf or floral bract has revealed that only the glandular trichomes' stalks remain, no effect will be felt after smoking the dried plant material from which the resin spheres have been removed.

(3) The electrostatic collection of the resin spheres from dried marijuana plants with plenty of ripe seeds has been for hundreds of years the method indigenous people of North Africa and Lebanon have used to make hashish. Obtain a round metal can 8" or so in diameter x 3" or so in depth (the kind that cookies come in) with a smooth lid. Obtain 2 ounces of dried marijuana with plenty of ripe seeds in the tops. To remove the seeds and stems, sift the marijuana tops through a 10-hole-to-the-inch wire kitchen strainer into the can. Close the can with the lid and vigorously shake the closed can three or four times. This gives the resin spheres an excess negative charge. Let the can sit for a moment and then remove the lid. Opposites attract. The negative-charged resin spheres have been attracted to the metal surface of the can and lid which has a positive charge. Take a matchbook cover or credit card and draw the edge across the surface of the lid. Note the collected powder. Observed under 300X magnification, the collected powder from this "shake" is composed of resin spheres with an occasional non-glandular trichome. As the marijuana is shaken again and again, and more of the yellow resin spheres are removed from the plant material, the collected powder gradually becomes green-colored as the number of non-glandular trichomes increases in the collected powder. The greener the powder, the less the effect.

(4) "Cannabinoids represent a dimer consisting of a terpene and a phenol component. Cannabigerol (CBG) is the first component of the pathway. It undergoes chemical change to form either cannabichromene (CBC), or cannabidiol (CBD). Delta 9-tetrahydrocannabinol (THC) is derived from CBD."

(5) "Pate (1983) indicated that in areas of high ultraviolet radiation exposure, the UVB (280-320 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 UVB has also been experimentally determined by Lydon et al. (1987)."

The writer's own experience allow for a more specific conclusion: If the UVB photon is missing from the light stream(a), or the intensity as expressed in µW/cm2 falls below a certain level(b), the phytochemical process will not be completely energized with only UVA photons which are more penetrating but less energetic, and the harvested resin spheres will have mostly precursor compounds and not fully realized THC(c).

(a)Examples of an environment where the UVB photon would be missing from the light stream include all indoor cultivation illuminated by HID bulbs and in glass or corrugated fiberglass covered greenhouses.

(b)"The maximum UVB irradiance near the equator (solar elevation angle less than 25 deg.) under clear, sunny skies is about 250 µW/cm2. It was observed that the daily solar UVB in Riyadh, Saudi Arabia (N24.4Lat.) decreased from September to December by about 40% (Hannan et al. 1984). The further a person is from the tropics, the less UVB radiation there is: the average annual exposure of a person living in Hawaii is approximately four times that of someone living in northern Europe." Below are some UVB readings taken in Hoyleton, Illinois, on a clear sunny day in June by David Krughoff as reported in Reptile Lighting 2000.

7am: 12 microwatts/cm2
8am: 74 microwatts/cm2
9am: 142 microwatts/cm2
10am: 192 microwatts/cm2
11am: 233 microwatts/cm2
12pm: 256 microwatts/cm2
1pm: 269 microwatts/cm2
2pm: 262 microwatts/cm2
3pm: 239 microwatts/cm2
4pm: 187 microwatts/cm2
5pm: 131 microwatts/cm2
6pm: 61 microwatts/cm2

(c)Cannabinoid pathway: Anywhere in this pathway UVB does a better job than UVA in energizing a phytochemical reaction that will produce more fully realized THC because "all cannabinolic compounds show an absorption maximum between 270 and 280 nm in the ultraviolet region."

(6) Capitate-stalked glandular trichome.

(7) #1: The ovum has been fertilized and there is a seed developing: In the areas of the Northern Hemisphere where indigenous people have grown heterozygous drug-type marijuana for hundreds of years, pollination is used to trigger the growth of the capitate-stalked glandular trichome on the floral bract and concomitant leaves of the flowering females before the autumnal equinox(a) so the majority of seeds will be ripe(b) before November.

(7) #2: The floral bract has become parthenocarpic: Parthenocarpic fruits develop without fertilization and have no seeds. Except for transmutation and turning lead into gold, there has been more nonsense written about seedless marijuana than on any other subject. In marijuana parthenocarpy, the floral bract (the fruit) enlarges in size as though there were a seed growing inside, and the capitate-stalked glandular trichome is triggered into growth on the floral bract and concomitant leaves. "Most popular supermarket tomatoes are parthenocarpic which was induced artificially by the application of dilute hormone sprays (such as auxins) to the flowers." In a trial, marijuana parthenocarpy was not induced by the application of the spray used on tomatoes. Only the photoperiod(c) will trigger parthenocarpy in flowering female marijuana plants. Marijuana parthenocarpy occurring before the autumnal equinox is considered by the author to be "long-day" and marijuana parthenocarpy occurring after the autumnal equinox to be "short-day".

The longest photoperiod that will trigger parthenocarpy in unfertilized flowering homozygous(d) Indica female marijuana plants is 13:00 hours, give or take 15 minutes. This effect can be obtained in the month of August at N35Lat, and because the capitate-stalked glandular trichomes received plenty of UVB during this month at this latitude, the harvested resin spheres had fully realized THC. Rating: euphoria and hallucinations, major appetite boost and pain relief, deep dreamless sleep. These plants seldom grow taller than four feet but potency makes up for the reduced harvest.

The gene pool is heterozygous if a flowering female marijuana plant is not parthenocarpic by the end of the first week in September in the Northern Hemisphere. If this is the case, pollination is used instead of parthenocarpy to trigger the growth of the capitate-stalked glandular trichome before the autumnal equinox to obtain as much fully realized THC as possible in the harvested resin spheres by the time the majority of the seeds are ripe.

The longest photoperiod that will trigger parthenocarpy in unfertilized flowering heterozygous female marijuana plants is 11:00 hours, give or take 15 minutes: This effect can be obtained in the month of November at N35Lat. Because of the low intensity of UVB radiation at this latitude at sea level during November, the harvested resin spheres evidenced only slightly more THC than precursor compounds. Rating: mild to medium euphoria, appetite boost and pain relief, good snooze.

Thai marijuana falls into this 11:00 hour category, and its parthenocarpy is characterized by an inflorescence in which many floral bracts are attached to an elongated meristem. It is these elongated meristems that are harvested to become a THAI STICK. On the other side of the world, Mexican marijuana grown around the same latitudes (Michoacan, Guerrero, Oaxaca) also falls into this short-day parthenocarpic category and the unfertilized marijuana will become "sensimilla" in the 11:00 hour photoperiod which begins in mid-December in that region. The winter sunshine in those latitudes has enough UVB intensity to produce fully realized THC--unlike the winter sunshine at N35Lat.

All unfertilized flowering female marijuana plants will become parthenocarpic in a 9:00 hour photoperiod (15:00 hour dark period): This can be obtained in the month of December at N35Lat. At this latitude in this month there is not even enough UVB in sunlight for precursor vitamin D3 to develop in human skin. The phytochemical process will not produce fully realized THC when UVB falls below a certain level of intensity expressed in µW/cm2. Rating: no effect.

(a)In the Northern Hemisphere above the Tropic of Cancer, the key to all marijuana potency is this: The more days of sunlight the capitate-stalked glandular trichomes' resin spheres accumulate before the autumnal equinox the more fully realized THC.

(b)It is recognized in the indigenous world that drug-type marijuana with a majority of ripe seeds will produce more euphoria, hallucinations, appetite stimulation, pain relief, and sleep aid than with a majority of unripe seeds.

(c)The photoperiodic response is controlled by phytochrome. "Phytochrome is a blue pigment in the leaves and seeds of plants and is found in 2 forms. One form is a blue form(Pfr), which absorbs red light, and the other is a blue-green form(Pr) that absorbs far-red light. Solar energy has 10X more red (660nm) than far-red (730nm) light causing the accumulation of Pfr." The first and last hour of a day's sunlight is mostly red light because of the scattering effect on blue light. "So at the onset of the dark period much of the phytochrome is in the Pfr form. However, Pfr is unstable and returns to phytochrome Pr in the dark." The red light in sunrise returns the Pr to the Pfr form. "Phytochrome Pfr is the active form and controls flowering and germination. It inhibits flowering of short-day plants (the long night period is required for the conversion of Pfr to Pr) and promotes flowering of long day plants."

(d)In Nepal and nearby areas of India where the capitate-stalked glandular trichome is triggered into growth by parthenocarpy rather than by fertilized ovum, great care is taken to make sure that all male marijuana plants are destroyed as soon as they reveal their sex. This is because unfertilized Indica flowering females can have both stigma and anther protruding from the floral bract. In the Indica gene pool, female-produced pollen carries an allele for long-day parthenocarpy, and seeds resulting from this female-produced pollen will produce another generation of female plants that will also exhibit long-day parthenocarpy during flowering. But if pollen from male plants is introduced into this gene pool, the resulting seeds will produce a generation of females that will exhibit short-day parthenocarpy instead. The allele for long-day parthenocarpy in the female-produced pollen is carried into the gene pool by self-pollination and cross-pollination, and perhaps homozygous is used too loosely here to describe the genetic result.

(8) It appears that the resin sphere acts as an UVB receptor and magnifying lens. The latter apparently lets it gather in a lot more photons than would otherwise be possible; because a lens also acts as a prism, the resin sphere may prevent some wavelengths from being focused where the phytochemical processes are taking place because they could interfere with the phytochemical process that makes THC.





electrostatic collection of resin spheres and non-glandular trichome

-------illuminated with 100 watt light bulb------- ---illuminated with sunlight---

© 2002 jknuc rev. April 2004
Bibliography - marijuana-optics.greatnow.com/

Marijuana THC


Buy Marijuana Seeds / Free Marijuana Grow Guide Library / Link with Green Man / World Listings / Affiliate Programs / Site Map / Marijuana Seeds

 

[indifferent]

This is absolutely required reading for anyone with any interest in how and why THC is produced, the key thing to note is that the resin head on a glandular trichome serves as a lens to focus UVB radiation into the phytochemical pathway that produces THC. In short, glandular trichomes are UVB receptors. it has been shown that Basil requires UVB in order to fill it's glandular trichomes with essential oils, basil grown without UVB lacks smell and taste. The same is true of cannabis, without UV it lacks something.

An elaboration on the phytochemical process that makes marijuana THC
The resin exuded by the glandular trichome forms a sphere that encases the head cells.

When the resin spheres are separated from the dried plant material by electrostatic attraction and placed on a microscope slide illuminated with a 100W incandescent bulb, they appear very dark when observed through a 300X microscope. Since orange, red, and infrared are the component wavelengths of incandescent light, and since the absorption of light makes an object dark or opaque to the frequency of the incoming wave, one can conclude that these wavelengths are probably not directly involved in energizing the cannabinoid pathway.

However, the resin sphere is transparent to ultraviolet radiation.

The author found through trial and error that only one glandular
trichome exhibits the phytochemical process that will produce the amount of THC associated with pain relief, appetite stimulation and anti-nausea; euphoria and hallucinations are side-effects, however. This trichome is triggered into growth by either of the two ways that the floral bract is turned into fruit.

Of all the ways that optics are involved in the phytochemical production of THC, the most interesting has to be how the head cells and cannabinoid molecules are tremendously magnified by the resin sphere. These and other facts are curiously absent from the literature. The footnotes update the literature to include electrostatic separation of the resin sphere from the dried plant material and marijuana parthenocarpy.


(1) "For all spheres, a ray drawn perpendicular to the sphere's surface will intersect the center of the sphere, no matter what spot on the surface is picked, and the magnifying power(a) of a glass sphere is greater the smaller its size. A sphere of glass can also bring light that is heading to a focus behind it to a point within it, with freedom from two aberrations, spherial aberration and coma, but not from chromatic aberration. Chromatic aberration results when different wavelengths are focused on different planes and is the most difficult of the aberrations to correct. The human eye lens also exhibits chromatic aberration, but a yellow pigment(b) called the macula lutea in the fovea, an area at the rear of the eyeball, corrects this problem by the way it absorbs blue light."

(a)"The formula to calculate the magnifying power of a sphere is l=333/d, where l is the magnifying power and d is the diameter of the sphere expressed in mm."

(b)Interestingly, the resin exuded by drug-type flowering female marijuana plants has a yellow tint. Could this pigment work to correct chromatic aberration in the resin sphere like the macula lutea does in the fovea for the eyeball?

(2) Quoting from the Mahlberg and Kim study of hemp(a) "THC accumulated in abundance in the secretory cavity where it was associated with the following: cell walls, surface feature of secretory vesicles, fibrillar material released from disc cell wall, and cuticle. It was not associated with the content of the secretory vesicles."

The resin spheres contain the THC. It is not contained in the leaf or floral bract. After the resin spheres are dissolved in solvent or dislodged by electrostatic attraction, and a microscopic examination of the leaf or floral bract has revealed that only the glandular trichomes' stalks remain, no effect will be felt after smoking the dried plant material from which the resin spheres have been removed.

(3) The electrostatic collection of the resin spheres from dried marijuana plants with plenty of ripe seeds has been for hundreds of years the method indigenous people of North Africa and Lebanon have used to make hashish. Obtain a round metal can 8" or so in diameter x 3" or so in depth (the kind that cookies come in) with a smooth lid. Obtain 2 ounces of dried marijuana with plenty of ripe seeds in the tops. To remove the seeds and stems, sift the marijuana tops through a 10-hole-to-the-inch wire kitchen strainer into the can. Close the can with the lid and vigorously shake the closed can three or four times. This gives the resin spheres an excess negative charge. Let the can sit for a moment and then remove the lid. Opposites attract. The negative-charged resin spheres have been attracted to the metal surface of the can and lid which has a positive charge. Take a matchbook cover or credit card and draw the edge across the surface of the lid. Note the collected powder. Observed under 300X magnification, the collected powder from this "shake" is composed of resin spheres with an occasional non-glandular trichome. As the marijuana is shaken again and again, and more of the yellow resin spheres are removed from the plant material, the collected powder gradually becomes green-colored as the number of non-glandular trichomes increases in the collected powder. The greener the powder, the less the effect.

(4) "Cannabinoids represent a dimer consisting of a terpene and a phenol component. Cannabigerol (CBG) is the first component of the pathway. It undergoes chemical change to form either cannabichromene (CBC), or cannabidiol (CBD). Delta 9-tetrahydrocannabinol (THC) is derived from CBD."

(5) "Pate (1983) indicated that in areas of high ultraviolet radiation exposure, the UVB (280-320 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 UVB has also been experimentally determined by Lydon et al. (1987)."

The writer's own experience allow for a more specific conclusion: If the UVB photon is missing from the light stream(a), or the intensity as expressed in µW/cm2 falls below a certain level(b), the phytochemical process will not be completely energized with only UVA photons which are more penetrating but less energetic, and the harvested resin spheres will have mostly precursor compounds and not fully realized THC(c).

(a)Examples of an environment where the UVB photon would be missing from the light stream include all indoor cultivation illuminated by HID bulbs and in glass or corrugated fiberglass covered greenhouses.

(b)"The maximum UVB irradiance near the equator (solar elevation angle less than 25 deg.) under clear, sunny skies is about 250 µW/cm2. It was observed that the daily solar UVB in Riyadh, Saudi Arabia (N24.4Lat.) decreased from September to December by about 40% (Hannan et al. 1984). The further a person is from the tropics, the less UVB radiation there is: the average annual exposure of a person living in Hawaii is approximately four times that of someone living in northern Europe." Below are some UVB readings taken in Hoyleton, Illinois, on a clear sunny day in June by David Krughoff as reported in Reptile Lighting 2000.

7am: 12 microwatts/cm2
8am: 74 microwatts/cm2
9am: 142 microwatts/cm2
10am: 192 microwatts/cm2
11am: 233 microwatts/cm2
12pm: 256 microwatts/cm2
1pm: 269 microwatts/cm2
2pm: 262 microwatts/cm2
3pm: 239 microwatts/cm2
4pm: 187 microwatts/cm2
5pm: 131 microwatts/cm2
6pm: 61 microwatts/cm2

(c)Cannabinoid pathway: Anywhere in this pathway UVB does a better job than UVA in energizing a phytochemical reaction that will produce more fully realized THC because "all cannabinolic compounds show an absorption maximum between 270 and 280 nm in the ultraviolet region."

(6) Capitate-stalked glandular trichome.

(7) #1: The ovum has been fertilized and there is a seed developing: In the areas of the Northern Hemisphere where indigenous people have grown heterozygous drug-type marijuana for hundreds of years, pollination is used to trigger the growth of the capitate-stalked glandular trichome on the floral bract and concomitant leaves of the flowering females before the autumnal equinox(a) so the majority of seeds will be ripe(b) before November.

(7) #2: The floral bract has become parthenocarpic: Parthenocarpic fruits develop without fertilization and have no seeds. Except for transmutation and turning lead into gold, there has been more nonsense written about seedless marijuana than on any other subject. In marijuana parthenocarpy, the floral bract (the fruit) enlarges in size as though there were a seed growing inside, and the capitate-stalked glandular trichome is triggered into growth on the floral bract and concomitant leaves. "Most popular supermarket tomatoes are parthenocarpic which was induced artificially by the application of dilute hormone sprays (such as auxins) to the flowers." In a trial, marijuana parthenocarpy was not induced by the application of the spray used on tomatoes. Only the photoperiod(c) will trigger parthenocarpy in flowering female marijuana plants. Marijuana parthenocarpy occurring before the autumnal equinox is considered by the author to be "long-day" and marijuana parthenocarpy occurring after the autumnal equinox to be "short-day".

The longest photoperiod that will trigger parthenocarpy in unfertilized flowering homozygous(d) Indica female marijuana plants is 13:00 hours, give or take 15 minutes. This effect can be obtained in the month of August at N35Lat, and because the capitate-stalked glandular trichomes received plenty of UVB during this month at this latitude, the harvested resin spheres had fully realized THC. Rating: euphoria and hallucinations, major appetite boost and pain relief, deep dreamless sleep. These plants seldom grow taller than four feet but potency makes up for the reduced harvest.

The gene pool is heterozygous if a flowering female marijuana plant is not parthenocarpic by the end of the first week in September in the Northern Hemisphere. If this is the case, pollination is used instead of parthenocarpy to trigger the growth of the capitate-stalked glandular trichome before the autumnal equinox to obtain as much fully realized THC as possible in the harvested resin spheres by the time the majority of the seeds are ripe.

The longest photoperiod that will trigger parthenocarpy in unfertilized flowering heterozygous female marijuana plants is 11:00 hours, give or take 15 minutes: This effect can be obtained in the month of November at N35Lat. Because of the low intensity of UVB radiation at this latitude at sea level during November, the harvested resin spheres evidenced only slightly more THC than precursor compounds. Rating: mild to medium euphoria, appetite boost and pain relief, good snooze.

Thai marijuana falls into this 11:00 hour category, and its parthenocarpy is characterized by an inflorescence in which many floral bracts are attached to an elongated meristem. It is these elongated meristems that are harvested to become a THAI STICK. On the other side of the world, Mexican marijuana grown around the same latitudes (Michoacan, Guerrero, Oaxaca) also falls into this short-day parthenocarpic category and the unfertilized marijuana will become "sensimilla" in the 11:00 hour photoperiod which begins in mid-December in that region. The winter sunshine in those latitudes has enough UVB intensity to produce fully realized THC--unlike the winter sunshine at N35Lat.

All unfertilized flowering female marijuana plants will become parthenocarpic in a 9:00 hour photoperiod (15:00 hour dark period): This can be obtained in the month of December at N35Lat. At this latitude in this month there is not even enough UVB in sunlight for precursor vitamin D3 to develop in human skin. The phytochemical process will not produce fully realized THC when UVB falls below a certain level of intensity expressed in µW/cm2. Rating: no effect.

(a)In the Northern Hemisphere above the Tropic of Cancer, the key to all marijuana potency is this: The more days of sunlight the capitate-stalked glandular trichomes' resin spheres accumulate before the autumnal equinox the more fully realized THC.

(b)It is recognized in the indigenous world that drug-type marijuana with a majority of ripe seeds will produce more euphoria, hallucinations, appetite stimulation, pain relief, and sleep aid than with a majority of unripe seeds.

(c)The photoperiodic response is controlled by phytochrome. "Phytochrome is a blue pigment in the leaves and seeds of plants and is found in 2 forms. One form is a blue form(Pfr), which absorbs red light, and the other is a blue-green form(Pr) that absorbs far-red light. Solar energy has 10X more red (660nm) than far-red (730nm) light causing the accumulation of Pfr." The first and last hour of a day's sunlight is mostly red light because of the scattering effect on blue light. "So at the onset of the dark period much of the phytochrome is in the Pfr form. However, Pfr is unstable and returns to phytochrome Pr in the dark." The red light in sunrise returns the Pr to the Pfr form. "Phytochrome Pfr is the active form and controls flowering and germination. It inhibits flowering of short-day plants (the long night period is required for the conversion of Pfr to Pr) and promotes flowering of long day plants."

(d)In Nepal and nearby areas of India where the capitate-stalked glandular trichome is triggered into growth by parthenocarpy rather than by fertilized ovum, great care is taken to make sure that all male marijuana plants are destroyed as soon as they reveal their sex. This is because unfertilized Indica flowering females can have both stigma and anther protruding from the floral bract. In the Indica gene pool, female-produced pollen carries an allele for long-day parthenocarpy, and seeds resulting from this female-produced pollen will produce another generation of female plants that will also exhibit long-day parthenocarpy during flowering. But if pollen from male plants is introduced into this gene pool, the resulting seeds will produce a generation of females that will exhibit short-day parthenocarpy instead. The allele for long-day parthenocarpy in the female-produced pollen is carried into the gene pool by self-pollination and cross-pollination, and perhaps homozygous is used too loosely here to describe the genetic result.

(8) It appears that the resin sphere acts as an UVB receptor and magnifying lens. The latter apparently lets it gather in a lot more photons than would otherwise be possible; because a lens also acts as a prism, the resin sphere may prevent some wavelengths from being focused where the phytochemical processes are taking place because they could interfere with the phytochemical process that makes THC.

 

[indifferent]

Hehehe B Friendly, you and I posted that at the same time!

Some more science I found on this subject:

Review
The effect of ultraviolet radiation on the accumulation of medicinal compounds in plants
Wen Jing Zhanga, b and Lars Olof Björna, c, ,
aLund University, Department of Cell and Organism Biology, Sölvegatan 35, SE-22362 Lund, Sweden
bQingHai Normal University, Key Laboratory of Resources and Environment in Qinghai-Tibet Plateau, Ministry of Education, Qinghai 810008, China
cKey Laboratory of Ecology and Environmental Science in Guangdong Higher Education, School of Life Science, South China Normal University, Guangzhou 510631, China
Received 8 January 2009; accepted 11 February 2009. Available online 23 February 2009.
Abstract
A review is given of how the production by plants of compounds useful as medicines or raw materials for manufacture of medicines is influenced by ultraviolet radiation, particularly by UV-B radiation (280–315 nm wavelength). The compounds considered in this review are flavonoids and other phenolics, alkaloids (especially indole terpenoid and purine alkaloids), essential oils and other terpenoids, cannabinoids, glucosinolates and isothiocyanates, and compounds having human hormone activity. A short account is also given of ultraviolet signalling in plants. The review concludes with a discussion of the possible evolutionary mechanisms that have led to the evolution of UV-B regulation of secondary metabolite accumulation.

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. (198 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.
Conclusions

Although the chemistry of Cannabis has come under extensive investigation, more work is needed to probe the relationship of its resin to biotic and abiotic factors in the environment. Glandular trichomes are production sites for the bulk of secondary compounds present. It is probable that the cannabinoids and associated terpenes serve as defensive agents in a variety of antidessication, antimicrobial, antifeedant and UV-B pigmentation roles. UV-B selection pressures seem responsible for the distribution of THC-rich Cannabis varieties in areas of high ambient radiation, and may have influenced the evolution of an alternate biogenetic pathway from CBG to THC in some of these strains. Though environmental stresses appear to be a direct stimulus for enhanced chemical production by individual plants, it must be cautioned that such stresses may also skew data by hastening development of the highly glandular flowering structures. Future studies will require careful and representative sampling to assure meaningful results.

Twenty years ago virtually nothing was known about the effects of UVR on plants (Teramura 1986). Even today knowledge is principally limited to the effects on agricultural crops; little is known of the effects of UVR in other natural ecosystems such as forests, meadows, savannas, tundra and alpine areas (Tevini and Teramura 1989).

The responses of plants to UV irradiation include physiological, biochemical, morphological and anatomical changes. Clearly more information is needed before a reliable assessment can be made on whether changes in ambient UVB are likely to affect significantly productivity.

Responses in surface structure and chemistry
Outdoor UV-B supplementation studies of higher plants involving modulated lamp banks have revealed some significant responses, but plant responses to UV-B generally seem to be more subtle than those based on exclusion studies. The most consistent response in higher plants was an increase in the concentrations of soluble leaf UV-B-absorbing compounds. Phenylpropanoids, e.g. hydroxycinnamic acid, cinnamoyl esters, and flavonoids, including flavones and flavonols, and anthocyanins provide a UV-A and UV-B screen in higher plants. The flavonoids responsible for UV screening vary from species to species, and most plants synthesize a range of compounds to provide more effective screening. So far, most of the studies have been made with summer-green species.
The studies with evergreens have shown that, in warm years, the production of soluble phenolics is higher compared to cold years. UV-B radiation and altitude alter the foliar flavonoid composition in forest tree species, such as Scots and ponderosa pine. The responses may be transient or long-lasting. Phenolics increase with needle age in Scots pine, black pine and ponderosa pine Enhanced UV-B radiation increased Scots pine needle cutinization and wall-bound phenolics as well as flavonoids, , which are important during the late winter and early spring.
The natural UV-screening mechanisms in evergreens have been shown to include UV light screening via reflectance of UV/violet light by the epidermis, UV light screening via reduction of transmission by special anatomical arrangement of epidermal cells as well as light-reflecting hyaline hypodermal cells, conversion of UV light via fluorescence and UV light screening by UV-screening substances in cell walls and on surfaces. In higher plants, anthocyanins and flavones increase in response to high visible light levels, and UV irradiation induces flavonoids, sinapate esters, isoflavonoids and psoralens, and in evergreens, diacylated flavonol monoglycoside induction, for example, has been detected and p-coumaric acid, ferulic acid and astragalins have been identified as UV-B-absorbing substances

Sharma (1975) reported a greater glandular trichome density on leaves of Cannabis growing in xeric circumstances. Paris et al. (1975a) have demonstrated a marked increase in the cannabinoid content of Cannabis pollen with decreased humidity. Murari et al. (1983) grew a range of Cannabis fiber cultivars in three climatic zones of Italy and found higher THC levels in those plants grown in the drier "continental" (versus "maritime") climate. Hakim et al. (1986) report that CBD-rich English Cannabis devoid of THC produced significant amounts of THC and less CBD, when grown in the Sudan. This trend was accentuated in their next generation of plants.

Why do plants need UV light?
UV increases the level of essential oils in mints & the production of resin by trichomes of relatives, UV is used for maximum yield and quality of these oils.
UV induces color development in flowers, essential for beautiful red veins in green Kale or Chard.
Full Power Flower - UV light needed to fully fill the glandular trichomes of basil. Plants of Ocimum basilicum L. were grown in the absence of UV light, both peltate and capitate glandular trichomes were incompletely developed in both mature and developing leaves, the oil sacs being wrinkled and only partially filled, there was a large decrease in the number of broken oil sacs among the peltate glands as the mature glands broke open, releasing volatiles. the number of glands and the qualitative or quantitative composition of the volatiles were badly affected by the lack of UV light.
Tasty Sunscreen?.With added UV light, an increased level of essential oils yields a more powerful scent and flavour. The essential oils also aid in the absorption of UV light , thus a sunscreen for plants. Plants in the wild produce their own kind of “sunscreen,” called flavonoids. Flavonoids screen out some of the more dangerous UVB-type radiation.

OK, what are these Flavonoids? Flavonoids are antioxidants in fruits, vegetables, tea, and wine - plant nutrients that belong to the polyphenol family. They are really good for you. Flavonoids are responsible for brilliant blues, purples, and greens, as well as yellows, oranges, and reds which cannot be attributed to carotenoids (found in carrots). Carotenoids are fat-soluble, while flavonoids are predominantly water-soluble. Flavonoids are found in more concentrated forms in beans and berries, but also red wine, green tea, and soy products, as well as many common fruits and vegetables. Products are have been developed using these molecules to battle cell and DNA damage involved in cancer, heart disease, diabetes and possibly brain degeneration, by neutralizing"free radicals". Research links them to reduced risks for cancer, heart disease, and other age-related degenerative diseases, as well as antioxidant protection of body fluids such as blood. They also may help prevent stroke, flu, tooth decay, and other ailments. Apple skins rich in flavonoids are discarded in all food products such as juices because the flavonoids in the skin cause cloudiness in the juice. A waste, when you consider the antioxidant activity in apple peel is potent enough to stop cancer cells growing. Flavonoid content is highest in the leaves of St. John's wort (you must know about this flower), and is at maximum concentration during full bloom. In the flowers, the content of flavonoids is highest at the start of flowering, falling during flowering. In tests, St. John's wort (flowers) had the highest content of flavonoids (11.71%) of any of 223 species tested.
Several hundred flavonoids can be found in plants, they are the compounds which affect colour, aroma and flavour.
COMMERCIAL APPLICATION - UV light slows foliar growth and stem length. Bedding plants are often grown from seedlings in greenhouses. The growing conditions in a greenhouse cause many plants to outstrip their containers, growing too tall to be easily transported by the time their color matures. Plants overly tall for their containers may also be aesthetically displeasing, which can hinder their marketing. Height control of greenhouse-grown plants has long been an issue in the bedding plant industry. Chemical growth regulators are often used on ornamentals but are not considered safe on vegetable crops. Using UV light (particularly UVB) to regulate growth is a relatively new, but much safer alternative that works on several bedding plant species as well as select vegetables, exposing plants such as impatiens, tomatoes and cucumbers to UV treatments for a few hours slows their foliar growth and stem length without reducing color or other favorable characteristics.

Colour of plants - where's that pigment from?

Colour depends on if your Sunscreen is sweet and on Acid? (not forgetting hydroxycinnamate) Anthocyanin production requires light for photosynthesis in the PAR range. Anthocyanins, such as cyanidin, provide a natural sunscreen for plants. Because the molecular structure of an anthocyanin includes a sugar, production of this class of pigments is dependent on the availability of carbohydrates within a plant. Anthocyanin color changes with pH, which is why soil acidity affects leaf color.

Some good info about UV radiation and reptile bulbs:

I would like to give some insight into UV light.
My background: I am currently studying to become an Exotic Veterinarian. I am working on my Thesis paper right now, on Metabolic Bone Diseases associated with reptiles. MBD is generally caused from lack of UV-B. All reptiles require UV-B to properly metabolize Vitamin D3. I also used to breed Panther Chameleons and Uromastyx.

UV-A light ranges between 320-400 nm, UV-B light ranges between 290-320 nm, and UV-C 180-290 nm. UV-C light is dangerous to all living organisms.
UV-B light cannot be transferred through normal glass. Glass will filter out UV-B light. The typical lizard lamps that produce UV-B light are not made from typical glass (ie. Silicate) but instead are made from quartz.
The typical reptile lamp that is a 7% or a 10.0 is kinda of tricky to figure out and it actually took several phone calls to many companies. I needed to know where they came up with the basis of 7% or 5.0 or 10.0 for my paper. I finally got a good answer as to what the 7% actually stands for from Exo Terra. It is somewhat hard to explain what the 7% or the 5.0 or the 10.0 UVB stands for. It is actually a relative rating based on levels taken on the equator with the sun directly over head. Now with that being said, 7% is actually only 7% of the actual UVB recieved mid day on the equator. I really see no harm running a 10.0 or a 5.0 or a 7% bulb during the entire photo period of the life cycle. I hope that helps a little.

 

[B. Friendly]

to funny indifferent. Here's the pics that goes with the article

(8) It appears that the resin sphere acts as an UVB receptor and magnifying lens. The latter apparently lets it gather in a lot more photons than would otherwise be possible; because a lens also acts as a prism, the resin sphere may prevent some wavelengths from being focused where the phytochemical processes are taking place because they could interfere with the phytochemical process that makes THC.


electrostatic collection of resin spheres and non-glandular trichome

-------illuminated with 100 watt light bulb------- ---illuminated with sunlight---

 

[indifferent]

Hehe, funny indeed, we bought picked up on the same piece of text as being the important bit too!

I'm keen to get some experimentation going. I'm using four types of supplemental fluoro tube for my experiment:

1. 10k Actinic Marine Blue, has loads of blue and a fair bit of UVA, mostly in the 380-400nm upper range.

2. Philips CLEO 15W 300mm tube. I bought a couple of 4-tube facial tanning units dirt cheap on ebay and have dismantled them to use the tubes, end caps and ballasts, these tubes have a strong UVA output and between 3 and 4% UVB which is much higher than a reptile tube and these things do hurt your eyes to look at.

3. UV Acrylic Nail Art curing 9W PL-S CFL, these are all UVA with the peak at 365nm.

4. Blacklight t5 15W, these are similar to the curing PL-S tubes but they peak at 350nm and have a tiny wee bit of UVB.

As well as this array of fluoros, I've bought a 100W Mercury Vapour lamp (again dirt cheap on ebay) and this is my primary UVB source, i will only run this lamp for between 1 and 3 hours in the middle of the 'day' period.

 

[indifferent]

i managed to find an abstract for that 1985 Lyndon study we keep seeing referenced:

UV-B RADIATION EFFECT ON PHOTOSYNTHESIS, GROWTH AND CANNABINOID PRODUCTION OF TWO Cannabis stavic CHEMOTYPES: by John Lyndon, USDA-ARS, Southern Weed Science Laboratory, P. O. Box 350, Stoneville, MS, 38776, USA: Alan H. Teramura, Department of Botany, University of Maryland, College Park, MD, 20742, USA., & C. Benjamin Coffman, USDA-ARS, Weed Science Laboratory, AEQ, I, Beltsville, MD, 20705, USA: Received August 29, 1986, accepted February 24, 1987: page 201 Although the mechanism is unknown, a relationship exists between cannabinoid content and the attitude altitude at which C. sativa is grown. Mobark et al., (197 suggested that the high-altitude environment was responsible for an increased population of propyl cannabinoids in plants grown in 1300m. The average total cannabinoid content of wild, mature (flowering) Indian C. sativa from elevations between 250m and 1000m was 2.43% (by dry weight); between 1000 m and 2000m was 3.01%; and above 2000m Was 1.39% (Turner et al., 1979). The cannabinoid content in four out of five of these mature Indian C. sativa variants decreased when grown at sea level in Mississippi, USA. One likely factor which may be of significance to cannabinoid production in both high-altitude and tropical environments is ultraviolet radiation. page 202 Pate (1983) reported that C. sativa populations originating from high UV-B environment contained little or no cannabidiol (CBD) but high levels of delta 9 - tetrahydrocannabinol (delta 9 - THC), while the opposite was true for population from low UV-B environments, and proposed that the two distinct C. sativa chemotypes (drug and fiber) evolved as a result of selective pressures brought about by UV-B radiation. Fairbairn and Liebmann (1974) reported that the delta 9 - THC content of leaf tissue from UV irradiated greenhouse-grown drug-type C. sativa was 23% greater than non- irradiated greenhouse-grown plants. However, neither the spectral distribution nor the daily dose of UV radiation . The objectives of this study were to test (a) The physiological and morphological insensitivity of both the drug and fiber types of C. sativa to UV-B radiation; and (b) to correlate this insensitivity with a change in production of delta 9 - THC or CBD in drug and fiber type plants, respectively. Material and Methods Page 203 Results....Only the delta 9 THC content in leaf and floral tissues of drug type plants increased significantly with UV-B radiation. page 204 Discussion page 205 The results presented here indicate that both types of vegetative C. sativa are physiologically and morphologically insensitive to UV-B radiation. The increased level of delta 9 - THC found in leaf tissues upon UV-B irritation may account for this insensitivity on the drug type plants. However, fiber-type plants showed no comparable change in the level of CBD which has similar UV-B absorption characteristics). Thus, the contribution of cannabinoids to the UV-B insensitivity in vegetative C. sativa is equivocal. Perhaps the background levels of CBD present in the fiber-type tissues were sufficient to protect the plant from UV-B radiation. Alternatively, other UV-B absorbing compounds such as flavonoids may account for this UV-B insensitivity. Flavonoids are the principle pigments associated with UV radiation greening in plants . Barrett et al (1985) reported the concentration of Cannflavin A (a flavonoid from C. sative) was similar in drug and fiber type leaf tissue, whereas Gellert et al (1974) reported relatively more flavonoids in drug than fiber type plants. Whether the quality and quantity of flavonoids in leaf tissues of the chemotypes in this study were sufficient to account for observed UV-B insensitivity was not determined. It should be pointed out, however that one should be cautions when extrapolating from greenhouse to field conditions in UV-B studies. In addition, when considering the distribution of C. sativa, one cannot overlook the fact that it is one of the oldest cultivated plants known to man. Thus, its present distribution may possibly be an artifact of man's cultural practices. In conclusion, the delta 9 THC content in leaf and floral tissues of greenhouse grown drug-type C. sativa 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.

http://www.hempforus.com/reseaag4.htm

This here has copies of most of the full bodies of text of published studies that you'd normally need to pay to see. The sources are cited at the beginning of each paragraph, so you could likely contact these people (If they're still at these places) and verify the inforrmation.

 

[B. Friendly]

the only lights i have used are these reptile lights:
http://www.exo-terra.com/en/products/compact_fluorescent_bulbs.php
I am really curious to see how your experiments work out.

Really hard to find bulbs that give this spectrum:
(5) "Pate (1983) indicated that in areas of high ultraviolet radiation exposure, the UVB (280-320 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 UVB has also been experimentally determined by Lydon et al. (1987)."

 

[indifferent]

The closest to a pure UVB spectrum you can get are those Philips TL-01 types, they have a peak output at 311nm and cover the entire UVB spectrum with no UVA or UVC.

My concern with the reptile bulbs is that they have so much more UVA than UVB that the UVA levels may be responsible for any noticeable effects in the plant and the UVB effects are no apparent as they are much smaller.

This is why I'm trying to use other types of bulbs - so I can discern the effects of UVA and UVB seperately, UVA is probably gonna stimulate terpenoids, flavonoics and other stuff, UVB is gonna stimulate THC. Probably I will get a philips TL-01 bulb eventually so I can try adding just UVB and just UVA.

The academic research has been done, what we need to do now is take the academic findings and use them to design effective grow systems, we have to put theory into practice and that is always the hard part. Think of the manhattan project, working out the maths of the physics behing nuclear fission was rather simple, but building the bomb itself was the greatest engineering task ever undertaken.

 

[B. Friendly]

so where trying to build the A-BOMB of the dope world, i c.
I'll checkout the phillips did not know they existed. gracias

 

[indifferent]

I think we are perhaps doing work as significant as that done by the fellas running the centrifuges at oak ridge enriching the uranium for the bomb in that we're the guys trying to make something out of the numbers crunched by the mega brains.

Took me a lot of reading f threads around the place to find out about that philips lamp, it's expensive but will work very well.

This is a Chinese manufacturer of the 20W 2 foot type:

http://www.alibaba.com/product-free/246293497/UV_Lamp_G40T10E.html

Here is the 9W PL-S type in philips' catalogue:

http://www.prismaecat.lighting.philips.com/ecat/Light/Details.aspx?fh_eds=%C3%9F&fh_location=//prof/en_GB/categories%3C{fepplg}/countries%3E{en_GB}/status%3E{act}&fh_refview=search&fh_search=12&fh_secondid=927901701207_2&left_nav=gb_en&tab=family

Here is the 20w 2 foot philips type:

http://www.prismaecat.lighting.philips.com/ecat/Light/ApplicationRouter.aspx?fh_secondid=928010001201_2&fh_location=%2f%2fprof%2fen_GB%2fcategories%3C{fepplg}%2fcountries%3E{en_GB}%2fstatus%3E{act}%2fcategories%3C{F_0012FEPPLG_3177_PHL_xumcol12}&fh_eds=%C3%9F&fh_refview=lister&tab=&family=&&left_nav=gb_en&

This place, Don's bulbs will probably have them for sale, they have three different philips UVB types listed, two are 300nm, one is 310nm:

http://www.donsbulbs.com/cgi-bin/r/b.pl/f|24inch|t12|g13|20w|310nm|rapid-start.html

 

[Ghostwolf]

Thanks "indifferent" and "B.Friendly" I've been trying to find testing and research of this nature for along time. In the 70's I read that article in High Times about the cannabis growing at higher elevations under stronger UV-B sun's ray's and how the THC production was significantly increased. And wanted to know who else has experimented with this subject. I've learned a lot more than I knew before here thanks to you and all the others here. I feel that I'm able to to try this kind of lighting on a micro grow and find out if I can do this right. I didn't know about the reptile UV-B CFL's. I was thinking that all I had to work with was Black Light tubes or CFL's. Now I see that there's really a lot out there to use for UV-B lighting like this. I was thinking of combining BL CFL's, Daylight CFL's and Soft White CFL's. I've tried to research this subject with some ridicule from a few, but now I feel like it was worth it that now you have proven me right and not to be full of crap after all. Again Thanks Ghostwolf

 

[amoril]

i dont have the time now, but ill be back in a few hours. thought id throw it out there though, let you all mull it over....

the article posted by both indifferent and B. Friendly is, effectively, bunk. Its a hypothesis, with little in the way of actual scientific evidence. unfortunately, the MJMan video on YouTube thats so popular, is also based on this article

in fact, the pictures with it, arent from that article at all. When I get back, ill find the link to the real article, with the pictures. The "Joe Knuc" article or whatever just jacked the photos from an actual scientific publication, and didnt even credit them. Itll make more sense when you see, I promise

 

[B. Friendly]

there's always another side. But unless you have used the bulbs you would not know. So from experience i can say that adding uva and uvb light did increase crystal production.
Another thing that is true is that some of the best varieties come from areas around the world that are close to the equator. Which has an increased spectrum of uvb light. So Amoril outside of nay saying and some dude's opinion please tell me you have something more.

 

[amoril]

there's always another side. But unless you have used the bulbs you would not know. So from experience i can say that adding uva and uvb light did increase crystal production.
Another thing that is true is that some of the best varieties come from areas around the world that are close to the equator. Which has an increased spectrum of uvb light. So Amoril outside of nay saying and some dude's opinion please tell me you have something more.

first, it almost sounds like youre pegging me a "naysayer" which is false. I use the same reptile bulbs that indifferent uses, and have for a while but thanks anyways

anyhow, the scientific publication which first produced the pictures, and is referred to in the article in question is here : http://www.hempreport.com/issues/17/malbody17.html

now, he goes on to make a few assertions.... but THC is formed enzymatically. it doesnt require a specific wavelength of light to directly trigger the reaction.

check this out, it goes into more detail about the chemical processes that govern cannabinoid synthesis. this is science, not unfounded pseudo-hypothesis. its a PDF, so that may take a second to load. be patient, youll be bookmarking this one

its from Leiden University, in the NL, in 2008. https://openaccess.leidenuniv.nl/dspace/bitstream/1887/13206/6/01.pdf

thats a little tough to follow if you dont read or speak "science" talk, but its oh-so-valuable. It lays out all secondary metabolites, not just cannabinoids.


its only when you look at the bigger picture, that you see the influence of UV light, IMO. I think I saw some links / quotes earlier about UVB's effect on flavanoid production, right? if not, ill track those down again too....

anyhow, its the increase of the compounds that are precursors to cannabinoids, IMO, that is how UV light plays a role. I currently run UV light through veg, to stimulate diverse terpenoid and phenolic profiles, and ideally, lead to a more diverse / fully realized cannabinoid profile.

how's that, B. Friendly?

 

[amoril]

specifically addressing the "article" in question, though....

on his footnotes (cause thats where the "good stuff" is anyhow )

#1 - the sphere concept is right, but there's no solid evidence that a cannabinoid head is a perfect sphere, and not slightly elliptical (which changes things entirely).

#2 is pointless, really. its covered in the links I provided at least

#3 isnt relevant

#4 is directly refuted by the link I provided from Leiden University. The spoiler, THC is directly derived from CBG, making it a primary cannabinoid pathway, 1 of 3. If you want details, you gotta read the article

#5 is all assertion, based on the assumption that he has been correct thus far. he hasn't so its all bunk.

#6 good work, CSGT

#7 is him applying a fancy term for "flowering". Seriously, re-read it and put "flowering" or a proper derivative, in place every time he refers to parthenocarpy. Then, youll see that he's really kinda pulling some shit out of his ass, as lots of factors come into play (root mass, nutrient, levels of stress, wavelength of light, maturation, individual plants genetics, etc...).

he's right about #7(c) though....for what thats worth

#8 it appears to have been pulled from his ass, really. there's no reason to support that claim, that the resin sphere serves as a UV magnifier

------------------------

no offense intended to both of you who quoted the article, but its just not accurate. I used to be a believer in it, but that just led to more research, and I found a lot that contradicts what he says, and the latter usually has supporting evidence.

the kicker, is that the chemicals we all agree are reactive to UV light, are the only ones that are permeable through the stalk of the capitate stalked glandular trichome (csgt). those chemicals are produced in sessile glands, iirc. I could have just pulled that from my ass, but I know theyre produced elsewhere, and permeate into the trichome through the stalk. thats in the first link i put out tonight.

thats why my conjecture, is that the benefit is in the pre-cursors

 

[B. Friendly]

Is uva and uvb found in nature, if so then i would want it over my girls. Also if mj has evolved under uv light then it would be fare to say the plant would not waste this light. I don't think is blowing smoke to say this.

 

[amoril]

Is uva and uvb found in nature, if so then i would want it over my girls. Also if mj has evolved under uv light then it would be fare to say the plant would not waste this light. I don't think is blowing smoke to say this.

so what youre saying is....

you didnt read anything I posted...thats cool, hopefully someone will read it, and not continue to act as though Im "nay-saying"

its all good man.

edit - what Im saying about the article, put simply, is that its almost kinda right, but for all the wrong reasons

 

[indifferent]

I read your posts, not read the paper you linked to, but will do later, way too high right now to focus on scientific literature as I'm not a scientist at all and have a limited grasp of plant biology.

My interest in using blue and UV light began with response curves that showed not only chlorophyll a and b curves but also the carotenoid curve and carotenoids respond strongly to blue light.

One small experiment with a UV/blue cfl later and I am seeing increased smell and colouration which leads me to conclude certain spectra of light can stimulate creation of various shit within the plant.

Also, I am sure that the greater the levels of terpenoids, flavonoids and cannabinods the better the smoke will be.

Therefore I;m supplementing the neglected 280-400 spectrum heavily to see what happens.

The science is all well and good, but I;m interested in what I can achieve using the currently available lights, my goal being to replicate the light conditions of the equator as i like to grow equatorial sativas and that is hard to do with traditional 400-700nm visible light sources.