Jump to content


Photo

Uv-A & Uv-B Rays And There Possible Effects On Growing Marijuana

uv rays spectrums 0calli thc

  • Please log in to reply
83 replies to this topic

#1 OFFLINE   0calli

0calli

    BLuNo$eR

  • Inactive Stoner
  • 882 posts
  • LocationDoWn bY THe BeEeAcH !!!!!!!!!

Contributor

Posted 30 September 2012 - 04:45 PM

Ok guy I got something for you please read I think I'm onto something here lol

Ok so pot plants produce resin to combat the effects from uv-a and uv-b rays , so sitting here in wallowing in my own self greatness aka stoned as fuk ! I came up with the idea that the sad but true thinning of our atmospheres protective layers is letting in from what science says alarming amounts of these rays Are penateating through and therefore we have an increase I read some where's of 150% more concentration of these rays compared to the fifties and sixties and part of the seventies , ok so my thought is this I know we great advances in Pot fertilizers lights feeding systems cross pollinating etc my thought is even with all this and what we do know about pot production of resin and it uses I'm willing to bet one of the major reasons our outdoor pot is so much stronger is because of the higher concentration of these uv-a and uv-b rays.

So what do ya guys think ?


here is a lotttt of info but I took my time to read and my understanding of the above question

was answered ten fold and some very worth the read if you really want your buds covered in

FROST !!!!


BUT DO REMEMBER THAT INCREASED RESIN PRODUCTION DOES NOT INCREASE CBN'S OR THC POTENCY


The Evolutionary Effects of Ultraviolet-B Radiation on the Psychoactive Potency and Cannabinoid Content of Cannabis sativa L. The Evolutionary Effects of Ultraviolet-B Radiation on the Psychoactive Potency and Cannabinoid Content of Cannabis sativa L.



After a review of some scientific literature relating to the psychoactive potency of Cannabis, it is the author's opinion that Ultraviolet-B type radiation is the single most important environmental factor for developing varieties with highly narcotic properties. Ultraviolet-B radiation (UV-B) is defined as that part of the electromagnetic spectrum between 280 and 315 nanometers.

Cannabis sativa has two main chemotypes, one almost devoid of psychoactive principals ("fiber-type") and the other with an abundance of said principals. This is actually where the taxonomical split between C. indica and C. sativa originated, when in 1793 Lamarck named Cannabis indica as a distinct species from Cannabis sativa because of slight morphological differences, but mainly because of the intense mind-altering effects after ingestion of C. indica, as opposed to the fiber-type C. sativa (Schultes and Hofmann, 1980(?)). Almost every "fiber-type" variety has been grown outside the range of intense levels of UV-B radiation, whereas the opposite is true for "drug-type" varieties. This can be seen in a chart made by David Pate for his Ph.D. dissertation for the University of Missouri, where he used the data of Small and Beckstead (1973), taking careful steps to disqualify any varieties whose origins could have been in question, and plotted their THC content in relation to their UV-B radiation intensity (Image 1), and also their THC to CBD ratio in relation to UV-B radiation intensity (Image 2). About the data he says,
Quote:
The remaining data (Table 1) are assumed to be plants native to their respective areas or introduced long enough ago to be well adapted. (Pate, 1979)
And,
Quote:
Higher levels of delta-9-THC are evident in plants from origins of intense UV-B (Fig. 26). Even with the rather non-specific data base used, the results are highly significant (prob. = .0001) and ambient UV-B levels of seed origin account for over 40% (r^2 = .409537) of the observed variation in % delta-9-THC content. As could be expected, there is also a negative correlation between % CBD and UV-B intensity. (Pate, 1979)
This is a rather interesting observation, and one that has been noted by Bouquet,
Quote:
In Egypt, when the Viceroy Mehemet Ali wished to create a navy, he got Cannabis http://www.rollitup.org/marijuana-seeds.php from Europe in order to obtain suitable fiber for cordage. New seed had to be brought periodically, because the hemp plants obtained soon became incapable of producing good textile fibers. On the other hand, they began to secrete abundant quantities of the inebriating resin. (Bouquet, 1950)
And,
Quote:
Hemp cultivated in the plains gradually loses the property of supplying active resin. (Bouquet, 1950)
Bergel reported similar findings when he wrote,
Quote:
When we were still working in this field we were told that the production of active resin, in any kind of Cannabis plant, depends entirely on the altitude of the plantation; for example, you get rich charas or bhang in Northern India only at a certain height above sea level. It was also reported that in order to obtain active resin one had to plant Cannabis in Germany or near Rosenheim not far from Munich, which again is above a certain altitude. (Bergel, 1965)
David Pate discusses Bouquet when he says,
Quote:
The work of Small and Beckstead (1973) has indicated a substantial biosynthesis of (delta-9-THC) in plants originating between 30 degrees North and South latitudes. This is complimented by their observations of high-latitude CBD-predominant strains and an intermediate chemotype from border areas. Is it only coincidence that this pattern follows latitudal increases of UV-B, with the 30 degrees North to 30 degrees South belt exposed to the greatest intensities? Certain regions somewhat outside this belt that are known for their Cannabis products (including Morocco, Afghanistan, Lebanon, and the Yarkand district of China) raise their crops at UV-B enriched altitudes. (Pate, 1979)
He goes on to say,
Quote:
One of the samples that Small et al. (1975) investigated originated from seed of a Mexican strain raised in Mississippi by Turner et al. for NIMH distribution as 'standardized http://www.rollitup.org.' This strain produced only 1.5 % (delta-9-THC) in Canada, about 50% of its content when grown in the more southerly location. ... one might plausibly suspect the ~150% UV-B exposure difference between the two locations (for the increase in delta-9-THC). (Pate, 1979)
Other data he found supporting his idea was from Davis et al., who in 1963 analyzed and plotted Cannabis from Morocco, Greece, Brazil, Canada, Switzerland, Germany, and a seizure sample thought to be from Mexico (Davis et al., 1963). In it, Davis found while comparing high latitudes and tropical climates that,
Quote:
Samples with the highest ratios (of delta-9-THC to CBN/CBD) came from regions whose sunshine was least attenuated by cloud cover, a variable affecting levels of UV-B irradiances. (Pate, 1979)
Not long after that, at the first symposium organized by the Institute for Drug Dependence, whose topic was Cannabis, the topic of UV-B radiation was slightly covered. In the discussion on biosynthesis, when Agurell was discussing the cannabinoid content from an experiment, this discussion took place,
Quote:
Haney: Were the plants you were working with grown outdoors, or under glass?
Miras: Outdoors.
Agurell: In a greenhouse, with U.V. tubing.
Haney: Ultra-violet light is a very important factor.
(Joyce and Curry, 1970)


He does hint at the reason why when he says,
Quote:
His (Small's) conclusion that there is a strong correlation existing between high-THC cannabinoid phenotypes and cultural selection for potent strains does not take into consideration that his data also reflects that individuals of phenotype I, considered drug Cannabis, are usually grown south of 35 degrees latitude. (Clarke, 1981)
Although Clarke would like to contribute this to longer days, he failed to realize that intense UV-B radiation is another important factor missing from climates outside 35 degrees North and South latitude.

In John Lydon's Ph.D. dissertation, he showed experimentally that Cannabis plants irradiated with intense UV-B had a higher content of delta-9-THC and a lower content of CBD than those without UV-B. Although his experiment did not use clones, he reported a significant 38% difference in the content of delta-9-THC. (Lydon, 1985). Another issue he reported about was that Cannabis was morphologically and physiologically insensitive to UV-B radiation. That means that the plant did not encounter any growth changes or health problems in an area of UV-B exposure equal to that of 3000 Meters above sea level at 0 degrees latitude. Also in his dissertation are two graphs that show the strikingly different cannabinoid contents between "fiber" and "drug" Cannabis with the "fiber-type" coming from high latitude origins and the "drug-type" coming from low latitudes originally (Images 4 and 5). He quotes a different article from David Pate (Pate, 1983) when he says that Pate,
Quote:
Proposed that the two distinct C. sativa chemotypes (delta-9-THC producing, drug type and CBD producing, fiber type) evolved as a result of selective pressures brought about by UV-B radiations. (Lydon, 1985)
In Pate's closing paragraph he says,
Quote:
The results of the experiment clearly indicate that individuals of Cannabis have been selected to produce large quantities of (delta-9-THC) in situations of high UV-B exposure. This seems to be the consequence of an advantage conferred by the organism by the UV-B screening properties of this compound. (Pate, 1979)
Pate does not get into finding out why this phenomenon occurs in his dissertation, but he does discuss it some time later in 1994 when he published the "Chemical Ecology of Cannabis." The papers subject was the environmental factors that affect the potency of Cannabis, and UV-B radiation is covered in detail. He says,
Quote:
... the more intense ambient UV-B radiation of the tropics, in combination with the UV-B lability of cannabidiol, may have influenced the evolution of an alternate biogenetic route from cannabigerol to tetrahydrocannabinol in some varieties. (Pate, 1994)
He explains later, saying,
Quote:
Their experiments (Lydon, 1987) demonstrate that under conditions of high UV-B exposure, drug-type Cannabis produce 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. (Pate, 1994)
He then gives two explanations for the phenomenon. First, THC would be more energetically efficient to produce because it would last longer as a UV-B blocker than CBD. The other explanation is,
Quote:
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. (Pate, 1994)

And also by Bassman when speaking in general of UV-B radiation's effects on plants,
Quote:
In addition, some secondary metabolites may increase with enhanced UV-B radiation, whereas concentrations of others may decrease. (Bassman, 2004)


There has been a large group of individuals in modern times, who for various reasons attempt to grow Cannabis indoors under artificial lighting for its narcotic properties. These individuals try to mimic the output of the sun as closely as possible in order to grow their plant to their highest potential, although intense UV-b radiation is never represented in their indoor environments, mainly due to lack of information on UV-B's effects on Cannabis potency. There have been a few select individuals who have gone through the pains to supplement their HID (High-Intensity Discharge, the most common type of lamp used for this purpose) lighting with UV-B producing lamps and reported their findings, with almost all of them reporting positive results. This was observed on the Internet Cannabis growing community Overgrow.com. On that website, there have been five people who've supplemented UV-B through the whole life cycle of a Cannabis plant, aallonharja, Alchemy Grower, middle_aged_crazy, maxgrow_de, and Sam_Skunkman.


Quote:
You can determine clear differences in between the UV powered plant and the other two ladies.

In support of the fact that Ultraviolet-B radiation positively influences the narcotic properties of Cannabis, one could look at the writings of Ed Rosenthal, an author who specializes in indoor Cannabis growing. He seems to believe that UV-B is important in growing a narcotically potent Cannabis plant. His advice has been taken by more people on indoor Cannabis growing than any other author, mostly from his "Ask Ed" column which appears in Cannabis Culture magazine, or his best selling books on Cannabis growing. There have been at least two "Ask Ed" articles that speak of UV-B radiation, both in a positive light.

The first is from the November 2002 issue of Cannabis Culture in an article entitled "Light Disagreement", where an individual claims that Metal Halide HID lamps are better for the flowering cycle because of the UV radiation emitted by them. The person claims,
Quote:
MH lamps produce more (Ultraviolet light) than HPS lamps and the more UV, the higher the potency climbs in normally high potency plants. (Rosenthal, 2002)
In response, while probably speaking of Lydon's dissertation, Rosenthal says,
Quote:
A researcher conducted a controlled experiment in a greenhouse. ... He found that the percentage of THC increased in a direct ratio with the increase in UVB light. This research confirms the adage that high altitude plants are more potent than those grown at low altitudes. If you look at old-world land races of Cannabis plants that have become adapted to the climate and latitude, the ratio of THC to CBD starts at 100:1 at the equator. At the 30th parallel (the Hindu Kush Valley) the plants have a ratio of 50:50. At the 45th parallel the ratio is near 1:100. This corresponds roughly with the amount of UVB light received at these latitudes. There is much more UVB at the equator than the 45th parallel. (Rosenthal, 2002)
The second instance of Mr. Rosenthal speaking on UV-B radiation is from the February 2003 issue of Cannabis Culture. In the article entitled "Metal Halide for Flowering?" Rosenthal says,
Quote:
Third, the lamps emit more UVB than HPS lamps, although still in very small amounts. The amount of UVB light plants receive is directly related to the quality of buds. The more UVB, the higher the quality. (Rosenthal, 2003)
Mr. Rosenthal's advice should not be taken lightly due to his reputation and widespread audience in the Cannabis growing community.

The scientific data has shown that intense levels of Ultraviolet-B radiation have been the single most important environmental factor in developing Cannabis varieties with highly narcotic properties. The environmental stress of UV-B radiation coupled with the obvious artificial or cultural selection carried out by the human race, has resulted in varieties of Cannabis with large quantities of the psychoactive principal delta-9-THC. It would seem that today, With the amount of high quality, highly narcotic Cannabis strains available today, it would seem that the last step would be to give the plant a supplemental dose of Ultraviolet-B type radiation equal to that of low-latitude or high-altitude environments in order to fully develop the biosynthetic pathway to THC with little or no CBD involved. The lack of UV-B radiation in a Cannabis growing environment would effect the potency of the mind-altering attributes, as in the plant would not be as narcotic as if there was a quantifiable level of UV-B radiation in the light. Highly potent Cannabis can be grown without UV-B radiation being represented due to intense cultural selection, although it would seem that almost all the strains grown today are originally from areas of intense UV-B radiation.

Ultraviolet-B radiation is the single most effective environmental stress to increase the psychoactive potency of Cannabis. In fact, it's evolutionary, and over the years, along with a human hand, it has played the most important role in developing Cannabis with large quantities of its main psychoactive principal, delta-9-THC.

UVB/Cannabis science report





Article: UV-B RADIATION EFFECTS ON PHOTOSYNTHESIS, GROWTH AND CANNABINOID PRODUCTION OF TWO Cannabis Sativa CHEMOTYPES.
By: JOHN LYDON, ALAN H. TERAMULA and C. BENJAMIN COFFMAN.
Department of Botany, University of Maryland, College Park, MD 20742, USA.

My estimated conclusion: "Add 3 x 26w UVB lights / m2 to your grow room and increase THC levels up to 30% in buds"

Read this science article regarding UVB lights effect on drug type cannabis originated from high heigted tropical areas with highly elevated UVB levels. In experiments with plants they have shown an increase of THC concentration levels in leaves (glands) from in a range from 22% - 48% depending on UVB intensity. In flower trichomes they got an increase between 15% - 32%. Thats staggering news! Now, this is laboratory conditions with UVB lights filtered to emitt in 300 nm wavelenght UVB light. It's widely known that THC UVB absorption properties range between 280 - 315 nm, so that is important. There's no longer any doubt in my mind that UVB boosts the THC potency of drug type cannabis, and that dont having UVB light is not realising the full potential of our dear plants!


Environmental Influence It takes high quality genetics to produce high quality http://www.rollitup.org, but genetics is only half of the equation. The genetic structure (genotype) only plays 50% of the role in determining the appearance and quality (phenotype) of a given plant. The other half is determined by environmental conditions such as light, temperature, humidity and soil nutrition. All these factors play a role in both the physical and chemical nature of http://www.rollitup.org%27s trichomes.
The best way to take a look at how environment affects THC production is to look where on the planet cannabis has naturally adopted a high THC profile. As cannabis has spread around the world it has taken on many different traits to help in its adaptation to varied areas. The best drug varieties have always been found at equatorial or high altitude locations. The one thing which both of these variables have in common is high light intensity and a large amount of ultraviolet (UV) light in the spectrum.
Recent Swiss trials in outdoor plots of clones grown at different altitudes have shown that there is correlation between higher altitude and increased potency (although there seems to be a trade off in yield). This likely means that THC-rich resins act to protect the plant and its seed from both higher light intensities and ultraviolet presence. It's no surprise that cannabis has developed a chemical to protect itself against the Sun's damaging UV rays, as they can be injurious to all forms of life.
http://www.cannabisculture.com/library/images/uploads/2159-19_tri.jpgIn a plant's search for survival, energy put towards unneeded processes is wasted energy. Therefore a high-THC plant grown in a low THC environment will likely produce a medium THC result.


  • greengenez, suntrust7, Reggaerican and 4 others like this

#2 OFFLINE   0calli

0calli

    BLuNo$eR

  • Inactive Stoner
  • 882 posts
  • LocationDoWn bY THe BeEeAcH !!!!!!!!!

Contributor

Posted 30 September 2012 - 04:48 PM

The 15w black light's I use for extra trich production are similar to these

http://www.rollitup.org/attachments/outdoor-growing/1958054d1325018835-uv-uv-b-rays-there-sl-2000blb__92476.jpg
http://www.rollitup.org/attachments/outdoor-growing/1958055d1325018836-uv-uv-b-rays-there-uranium-marbles.jpg
  • DarKwon, SRH88 and RoofCraig like this

#3 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 30 September 2012 - 08:01 PM

I get more than my share from the hydrogen fusion light system I use. No scientific readings but usually 10+ most the time. Buds tend to be pretty gummy, even when bone dry. I live at 4000ft in So. Az.
  • greengenez, GoodOleDog, 0calli and 2 others like this

#4 OFFLINE   0calli

0calli

    BLuNo$eR

  • Inactive Stoner
  • 882 posts
  • LocationDoWn bY THe BeEeAcH !!!!!!!!!

Contributor

Posted 30 September 2012 - 08:12 PM



I get more than my share from the hydrogen fusion light system I use. No scientific readings but usually 10+ most the time. Buds tend to be pretty gummy, even when bone dry. I live at 4000ft in So. Az.


  • DarKwon, SRH88 and tiltswitch like this

#5 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 01 October 2012 - 05:01 AM

Cool vid .

How'd that Critical Overdrive come out or have you run it yet? My CO cross to Urban Poison came out quite nice.Ran them outdoors. Hence my hydrogen fusion lighting...
  • onehit57 likes this

#6 OFFLINE   PureGro1

PureGro1
  • LocationBeast Coast

Contributor

Posted 01 October 2012 - 10:01 AM

Great post O, I am interested in this....

Im going to re-read this a couple of times and make sure im understanding what is being said, a few things stick out to me

By the way im reading its being said that altitude should affect potency, But Co is highest state here with cali and fla in a tie with deleware for lowest state here in US. There is no disernable difference in weed potency and if anything I would say fla and cali have been known for good weed longer than Co.

I think there mixing some things up and I dont see them speak about- THC-V which is where I think there going off track, accounting the THC value...

what we do know about pot production of resin and it uses I'm willing to bet one of the major reasons our outdoor pot is so much stronger is because of the higher concentration of these uv-a and uv-b rays.

BUT DO REMEMBER THAT INCREASED RESIN PRODUCTION DOES NOT INCREASE CBN'S OR THC POTENCY


I think you answered your own question here at the end, You can grow as strong a Pot indoor today as you can outdoor- IMO- pot hasnt gotten stronger but good genetics have made a mass proliferation and you dont see the BADDDDD stuff we used to see so much anymore. Its the free market of Pot, Competition has brought out better and better genetics
  • roofwayne, DarKwon, SRH88 and 3 others like this

#7 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 01 October 2012 - 11:17 AM

I think there's a trade off
UV destroys THC also...
  • The Yorkshireman and 0calli like this

#8 OFFLINE   0calli

0calli

    BLuNo$eR

  • Inactive Stoner
  • 882 posts
  • LocationDoWn bY THe BeEeAcH !!!!!!!!!

Contributor

Posted 02 October 2012 - 06:24 PM

I think there's a trade off
UV destroys THC also...

ive heard what your saying but is it based on a live plant to a harvested one is my question for this known fact of uv degrading THC
  • RoofCraig likes this

#9 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 05 October 2012 - 01:02 PM

I think UV index, for outdoors, may be telling. The equatorial sun at sea level [if HI counts] does not feel as hot, but WILL burn you pretty seriously...
  • Theowl likes this

#10 OFFLINE   Brick Top

Brick Top

    Losing Lighters

  • Inactive Stoner
  • 56 posts
  • LocationThe Confederate States of America

Posted 14 October 2012 - 05:40 AM

Bits from a research study about the effects of UV-B light waves on medicinal elements in plants. Not all of it is about cannabis plants, but when it comes to plant biology cannabis plants are not radically different in how they react to the same elements, conditions and environment.

The most potent natural strains, those created by 'Mother Nature,' evolved in the tropical zone and in the sub tropical zone, between 30 degrees North and South latitude. The natural strains that evolved there were highest in THC and lowest in CBD. Of the other most potent natural strains they evolved at high altitudes, though some did have higher levels of CBD than the tropical and sub tropical strains. But what they all shared, what they all had in common in their highly diverse environmental regions, where each evolved, is increased levels of UV-B light waves.

UV-B light waves are filtered out by the atmosphere and the shorter distance they have to travel through the atmosphere, either due to being closer to the equator or by being at high altitude, the more intense the UV-B rays are that strike plants growing there.

That, being increased levels of UV-B light waves, is the singular common factor shared by the most potent natural strains ever regardless of where around the planet they evolved. That cannot be overlooked by anyone wishing to 'tickle out' the highest degree of potency, and also medicinal value, from the plants they grow, though potency (as in high levels of THC) and the greatest amount of medicinal value do not always go hand in hand.



Review
The effect of ultraviolet radiation on the accumulation of medicinal
compounds in plants
Wen Jing Zhang a,b, Lars Olof Björn a,c,⁎
a Lund University, Department of Cell and Organism Biology, Sölvegatan 35, SE-22362 Lund, Sweden
b QingHai Normal University, Key Laboratory of Resources and Environment in Qinghai-Tibet Plateau, Ministry of Education, Qinghai 810008, China
c Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, School of Life Science, South China Normal University, Guangzhou 510631, China


Essential oils and terpenoids
Essential oils constitute a heterogeneous collection of
chemical compounds. They have in common that they are
synthesized by plants and are volatile and mostly soluble in
ethanol. They have traditionally been obtained from plants
by extraction and distillation. Since the middle ages, they
have been widely used for insecticidal, medicinal and cosmetic
purposes. For a detailed review of their biological effects
the reader is referred to Bakkali et al. [80]. Schelz et al.
[81] have assayed antimicrobial effects of several of them.
Some essential oil compounds are terpenoids, i.e. a class of
hydrocarbons and derivatives of them. The substances from
Glycyrrhiza and yew dealt with at the end of this section are
also terpenoids.
Karousou et al. [82] studied two different chemotypes of
Mentha spicata, and found that in one of them UV-B radiation,
on a dry weight basis, caused a 50% increase in essential oil
production, while in the other chemotype the increase was
insignificant.
A more thorough investigationwas carried out by Johnson
et al. [22] on essential oil production in sweet basil (Ocimum
basilicum L.), in which the effect of ultraviolet radiation is
much greater. They separately analyzed no less than 22 different
essential oil compounds in this plant. The effect of
UV-B radiation increased with the age of the plants, and was
different for different compounds, but mostly positive. At
the 5 leaf stage the irradiated plants contained between 3
and 4 times as much of most essential oil components as did
the unirradiated control plants. In a later paper [83] by the
same group, the authors reported that UV-B radiation is
necessary for normal development of oil glands in sweet
basil. There seems to be a requirement for UV-B in the filling
of the glandular trichomes of this plant.


Cannabinoids
Pate [95] cites older literature suggesting that UV-B radiation
promotes cannaboid production in Cannabis and also
speculates about cannaboid evolution. Plots of estimated UV-B
exposure in different growth places shows an increase in Δ9-
tetrahydrocannabinol (Δ9-THC) with exposure, but a decrease
in cannabidiol. Lydon [96] and Lydon et al.[97] found that in
both leaf and floral tissues the concentration of Δ9-THC but not
of other cannabinoids increased linearly with UV-B exposure
in drug-type Cannabis sativa plants (Fig. 7), but not in fibertype
plants of the same species. Nowadays many sites on the
Internet show that the dependency of cannabinol accumulation
on UV-B radiation is common knowledge among private
entrepreneurs in the drug industry. The biosynthetic pathway
of cannabinoid synthesis is shown in Fig. 8.
It is not known which enzyme or enzymes for Δ9-
tetrahydrocannabinol biosynthesis are induced or stimulated
by UV-B radiation, but one can speculate. The gene for polyketide
synthase catalyzing the synthesis of olivetolic acid
possesses strong sequence homology with chalcone synthase
and may have evolved from this. Chalcone synthase is one of
the classic UV-B-regulated enzymes.


Conclusion
We have seen that the contents of medicinal substances of
many kinds in many plants are increased by exposure to
ultraviolet radiation, and in particular UV-B radiation. This
effect is not always regarded as a stress phenomenon, as in
many cases the increase in the secondary metabolites can be
achieved by radiation so low that they do not negatively affect
growth, and do not result in any visible damage. Thus, in order
to make the production of medicinal plant substances efficient,
it may be advisable to try exposure to ultraviolet radiation
also in cases which have not yet been investigated. I some cases UV-A or UV-C radiation may be more suitable
than UV-B.


http://www.elsevier....ote_80_p207.pdf


  • PureGro1, DarKwon, 0calli and 2 others like this

#11 OFFLINE   Brick Top

Brick Top

    Losing Lighters

  • Inactive Stoner
  • 56 posts
  • LocationThe Confederate States of America

Posted 14 October 2012 - 05:52 AM

A few quotes on the effects of UV-B light waves, some sue to outdoor growing and in particular at lower latitudes where there are increased levels of UV-B light waves.


UVB LIGHT

Ultra-violet B light is a spectrum of light that is invisible to us but is visible to insects and some other organisms. In humans it causes suntan and sunburn and is implicated in the formation of eye cataracts. It is the light emitted by tanning bulbs.

UVB light also affects marijuana potency. The potency of high quality marijuana increases in direct ratio to the amount of UVB light it receives.

Ed Rosenthal's Marijuana Grower's Handbook





Plots of estimated UV-B exposure in different growth places shows an increase in Δ9-tetrahydrocannabinol (Δ9-THC) with exposure, but a decrease
in cannabidiol.
That fits the pattern of sativas, and in particular the more equatorial sativas that are high in THC but very low in CBD.

It is not known for sure which enzyme or enzymes for Ä9-tetrahydrocannabinol biosynthesis are induced or stimulated by UV-B radiation, but one can speculate. The gene for polyketide synthase catalyzing the synthesis of olivetolic acid possesses strong sequence homology with chalcone synthase and may have evolved from this. Chalcone synthase is one of the classic UV-B-regulated enzymes.


Back as far as 2002 in an article titled Pot Potency Cannabis Culture Magazine said:



Environmental Influence

It takes high quality genetics to produce high quality marijuana, but genetics is only half of the equation. The genetic structure (genotype) only plays 50% of the role in determining the appearance and quality (phenotype) of a given plant. The other half is determined by environmental conditions such as light, temperature, humidity and soil nutrition. All these factors play a role in both the physical and chemical nature of marijuana's trichomes.

The best way to take a look at how environment affects THC production is to look where on the planet cannabis has naturally adopted a high THC profile. As cannabis has spread around the world it has taken on many different traits to help in its adaptation to varied areas. The best drug varieties have always been found at equatorial or high altitude locations. The one thing which both of these variables have in common is high light intensity and a large amount of ultraviolet (UV) light in the spectrum.

Recent Swiss trials in outdoor plots of clones grown at different altitudes have shown that there is correlation between higher altitude and increased potency (although there seems to be a trade off in yield). This likely means that THC-rich resins act to protect the plant and its seed from both higher light intensities and ultraviolet presence. It's no surprise that cannabis has developed a chemical to protect itself against the Sun's damaging UV rays, as they can be injurious to all forms of life.

http://www.cannabisculture.com/articles/2159.htm


In 2009 Cannabis Culture Magazine had an article called Inside the Trichome where it said:




Inside the Trichome

THC and other cannabinoids are produced in only one place on the cannabis plant: inside the heads of the trichomes. How it happens: Organelles produced by the plant called Vacuoles – which contain phenols, a chemical compound similar to alcohol [pictured at right in blue], and another type of organelle called plastids – containing hydrocarbons called terpenes [red], make their way up the trichome stalk [green] and combine inside the secretory cavity into a fibrous mat [yellow]. This concentrated mat is hit by UV-B light waves, causing the creation of cannabinoids.

http://www.cannabisculture.com/content/2009/06/11/Inside-Trichome




In the Sept. 11th, 2011 High Times an article written by HERB SPADOWSKI, PH.D. touched on light quality. It said:

Another study-this one preformed in Indiana University by two researchers named Maahlberg and Hemphill-tested THC content in the leaves of cannabis plants grown under sunlight, red light, blue light, green light, or complete darkness. The experiment revealed that the plant grown under the sunlight had the highest THC concentration.




Ask Ed Marijuana Grow Tip #41: Spring Has Sprung

Posted by Ed Rosenthal on Thursday, April 12, 2012 · 2 Comments

Has spring sprung in your area? Do the evenings stay above 50 degrees and does it get up into the seventies during the day? If it does, you can start a spring crop. You’ll grow the plants vegetatively for a month or two, and then place them into flowering. The plants won’t be very large when they are mature, but they will be very potent because the flowers will be maturing during a time of increasing UV light. By the time they come in, in early summer, UV will be at its peak. The advantage of this is that the quality of the plants – that is, the percentage of THC – increases with increasing UV light.

Ask Ed Marijuana Grow Tip #41: Spring Has Sprung : EdRosenthal.com


From Spiritridge Medicinals, Mendocino County, CA.


Quote:

Some people believe that marijuana grown indoors has a higher THC content. One important contributing factor to the level of THC in marijuana is the amount of ultraviolet light that the plant gets during it flowering stage.

Spirit Ridge Medicinals



I did not read the Feb 2012 High Times but I did read where in it Greg Green said supplemental UV lighting does increase potency.




Posted Image




Get More THC From Your Medical Marijuana Plants Using UV Light

August 24 2012

What if I told you that increasing the potency of your favorite strains was as easy as hanging up a few 20 watt florescent lights? To good to be true? More like too true not to do. It turns out the same thing baking your skin at the beach can make prized buds swell with THC. Ultra-violet (UV) light has the power to turn a good strain into a real head-knocker.
What Is UV Light?

At this point you might be asking, "how is UV light different from normal light?" Even though humans can't see it, a good way to think of UV is to visualize a rainbow and pretend there is an extra color band past the blue and purple. All light is basically just waves of energy, and UV light is just like any other form of radiation. These waves wash over your plants at different frequencies (how many waves pass per second). UV light has a smaller gap between each wave than visible light, which means more waves are passing per second. This gives UV high energy, making it more like an X-ray than a radio wave.

How Does UV Light Effect Marijuana Plants?

But what does all this mean to your cannabis garden? To answer that, we need to investigate how UV light affects plants cells. Ultra-violet radiation, particularly UVB, has been shown to be detrimental to plant cell function. UV causes damage to plant cells in the same way it tears through your skin, eventually causing sunburn. As a result of this damage, all plants have created defenses against UV in the form of gene UVR8.

UVR8 is a protein molecule which senses UV all by itself, and then "tells" plant cells to change their behavior. Exactly how UVR8 molecules sense UV was recently discovered and is pretty interesting. UVR8 is what chemists call a "dimer." which just means that it's made of two structurally similar protein subunits. When UV light hits the two protein subunits in UVR8, their charge weakens and they break apart. To help visualize this, imagine rubbing two balloons against one another. The balloons will stick together because of a static charge. Now imagine the balloons get rained on. The water takes the static charge with it and the two balloons fly apart. In this example, the balloons are the two protein subunits and the rain is UV light cascading down on the plant cell. After the protein subunits break apart, they head to the cell nucleus to deliver their information.

More UV Can Mean More THC



One of these changes caused by this information is very important in your cannabis garden. UV stress stimulates cannabis' production of chemicals via the phenylpropanoid pathway, specifically malonyl-CoA and phenylalanine. Why is this important? It's important because cannabis uses malonyl-CoA to make Olivtol, which it in turn uses to make THC. Now we can see the specific pathway which cannabis uses to increase potency when exposed to UV light.

UV light is already present in your garden, but it's being blocked by the special glass your bulb is made of. Lamp manufacturers must use this type of glass by law because UV light can cause skin cancer when humans are overexposed. You wouldn't want everyone getting cancer from street lights would you? You can increase the amount of UV getting to your cannabis by mixing metal halide bulbs into your bloom room and leaving the glass off your air-cooled hoods. But a better and safer way is to buy and install cheap fluorescent UV lights.

Remember, UV light causes stress to the plant, so put the fluorescents on timers and only have them on for part of the light cycle. Having them on for fifteen minutes of every hour should do the trick. The only downside of this whole process is that yields go down slightly. The plant has to reroute resources and undergoes some physical damage from the UV. As long as you don't overdo the UV the increase in quality is well worth the decrease in yield.

Get More THC From Your Medical Marijuana Plants Using UV Light | BigBuds Magazine - Your one source for growing medical marijuana


  • PureGro1, DarKwon, The Yorkshireman and 2 others like this

#12 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 14 October 2012 - 05:59 AM

Hi Bricktop,
This info is confirming what I've been telling the folk around here for a while.
....I'm not a great grower. I live in a superior growing climate. 4000ft ele in southern AZ. Air is dry and clear. UV index of 10+ most the time and very few cloudy days.
  • PureGro1, 0calli, RoofCraig and 1 other like this

#13 OFFLINE   Brick Top

Brick Top

    Losing Lighters

  • Inactive Stoner
  • 56 posts
  • LocationThe Confederate States of America

Posted 14 October 2012 - 06:12 AM

All these strains had one thing in common as they evolved and as they grow today in their natural regions, increased levels of UV-B light waves due to the latitude they evolved in/are in.

a) Colombia - (0 to 10 north latitude)

Colombian Cannabis originally could be divided into two basic strains: one from the low-altitude humid coastal areas along the Atlantic near Panama, and the other from the more arid mountain areas inland from Santa Marta. More recently, new areas of cultivation in the interior plateau of southern central Colombia and the highland valleys stretching southward from the Atlantic coast have become the primary areas of commercial export Cannabis cultivation. Until recent years high quality Cannabis was available through the black market from both coastal and highland Colombia. Cannabis was introduced to Colombia just over 100 years ago, and its cultivation is deeply rooted in tradition. Cultivation techniques often involve transplanting of selected seedlings and other individual attention. The production of "la mona amarilla" or gold buds is achieved by girdling or removing a strip of bark from the main stem of a nearly mature plant, thereby restricting the flow of water, nutrients, and plant products. Over several days the leaves dry up and fall off as the flowers slowly die and turn yellow. This produces the highly prized "Colombian gold" so prevalent in the early to middle 1970s (Partridge 1973). Trade names such as "punta roja" (red tips [pistils] ), "Cali Hills," "choco," "lowland," "Santa Marta gold," and "purple" give us some idea of the color of older varieties and the location of cultivation.

In response to an incredible demand by America for Cannabis, and the fairly effective control of Mexican Cannabis importation and cultivation through tightening border security and the use of Paraquat, Colombian farmers have geared up their operations. Most of the marijuana smoked in America is imported from Colombia. This also means that the largest number of seeds available for domes tic cultivation also originate in Colombia. Cannabis agri-business has squeezed out all but a few small areas where labor-intensive cultivation of high quality drug Cannabis such as "Ia mona amarilla" can continue. The fine marijuana of Colombia was often seedless, but commercial grades are nearly always well seeded. As a rule today, the more remote highland areas are the centers of commercial agriculture and few of the small farmers remain. It is thought that some highland farmers must still grow fine Cannabis, and occasional connoisseur crops surface. The older seeds from the legendary Colombian strains are now highly prized by breeders. In the heyday of "Colombian gold" this fine cerebral marijuana was grown high in the mountains. Humid lowland marijuana was characterized by stringy, brown, fibrous floral clusters of sedative narcotic high. Now highland marijuana has become the commercial product and is characterized by leafy brown floral clusters and sedative effect. Many of the unfavorable characteristics of imported Colombian Cannabis result from hurried commercial agricultural techniques combined with poor curing and storage. Colombian seeds still contain genes favoring vigorous growth and high THC production. Colombian strains also contain high levels of CBD and CBN, which could account for sedative highs and result from poor curing and storage techniques. Domestic Colombian strains usually lack CBD and CBN. The commercial Cannabis market has brought about the eradication of some local strains by hybridizing with commercial strains.


Colombian strains appear as relatively highly branched conical plants with a long upright central stem, horizontal limbs and relatively short internodes. The leaves are characterized by highly serrated slender leaflets (7-11) in a nearly complete to overlapping circular array of varying shades of medium green. Colombian strains usually flower late in temperate regions of the northern hemisphere and may fail to mature flowers in colder climates. These strains favor the long equatorial growing seasons and often seem insensitive to the rapidly decreasing daylength during autumn in temperate latitudes. Because of the horizontal branching pattern of Colombian strains and their long growth cycle, pistillate plants tend to produce many flowering clusters along the entire length of the stem back to the central stalk. The small flowers tend to produce small, round, dark, mottled, and brown seeds. Imported and domestic Colombian Cannabis often tend to be more sedative in psychoactivity than other strains. This may be caused by the synergistic effect of THC with higher levels of CBD or CBN. Poor curing techniques on the part of Colombian farmers, such as sun drying in huge piles resembling com post heaps, may form CBN as a degradation product of THC. Colombian strains tend to make excellent hybrids with more rapidly maturing strains such as those from Central and North America.


B) Congo - (5 north to 5 south latitude)


Most seeds are collected from shipments of commercial grade seeded floral clusters appearing in Europe.
d) India Centra1 Southern - Kerala, Mysore, and Madras regions (10 to 20 north latitude)


Ganja (or flowering Cannabis tops) has been grown in India for hundreds of years. These strains are usually grown in a seedless fashion and are cured, dried, and smoked as marijuana instead of being converted to hashish as in many Central Asian areas. This makes them of considerable interest to domestic Cannabis cultivators wishing to reap the benefits of years of selective breeding for fine ganja by Indian farmers. Many Europeans and Americans now live in these areas of India and ganja strains are finding their way into domestic American Cannabis crops.


Ganja strains are often tall and broad with a central stalk up to 12 feet tall and spreading highly-branched limbs. The leaves are medium green and made up of 7 to 11 leaf lets of moderate size and serration arranged in a circular array. The frond-like limbs of ganja strains result from extensive compound branching so that by the time floral clusters form they grow from tertiary or quaternary limbs. This promotes a high yield of floral clusters which in ganja strains tend to be small, slender, and curved. Seeds are usually small and dark. Many spicy aromas and tastes occur in Indian ganja strains and they are extremely resinous and psychoactive. Medicinal Cannabis of the late 1800s and early 1900s was usually Indian ganja.


e) Jamaica - (18 north latitude)


Jamaican strains were not uncommon in the late 1960s and early 1970s but they are much rarer today. Both green and brown varieties are grown in Jamaica. The top-of-the-line seedless smoke is known as the "lamb's bread" and is rarely seen outside Jamaica. Most purported Jamaican strains appear stringy and brown much like low land or commercial Colombian strains. Jamaica's close proximity to Colombia and its position along the routes of marijuana smuggling from Colombia to Florida make it likely that Colombian varieties now predominate in Jamaica even if these varieties were not responsible for the original Jamaican strains. Jamaican strains resemble Colombian strains in leaf shape, seed type and general morphology but they tend to be a little taller, thinner, and lighter green. Jamaican strains produce a psychoactive effect of a particularly clear and cerebral nature, unlike many Colombian strains. Some strains may also have come to Jamaica from the Caribbean coast of Mexico, and this may account for the introduction of cerebral green strains.


f) Kenya - Kisumu (5 north to 5 south latitude)


Strains from this area have thin leaves and vary in color from light to dark green. They are characterized by cerebral psychoactivity and sweet taste. Hermaphrodites are common.

h) Malawi, Africa - (10 to 15 south latitude)


Malawi is a small country in eastern central Africa bordering Lake Nyasa. Over the past few years Cannabis from Malawi has appeared wrapped in bark and rolled tightly, approximately four ounces at a time. The nearly seedless flowers are spicy in taste and powerfully psycho active. Enthusiastic American and European Cannabis cultivators immediately planted the new strain and it has be come incorporated into several domestic hybrid strains. They appear as a dark green, large plant of medium height and strong limb growth. The leaves are dark green with coarsely serrated, large, slender leaflets arranged in a narrow, drooping, hand-like array. The leaves usually lack serrations on the distal (tip portion) 20% of each leaflet. The mature floral clusters are sometimes airy, resulting from long internodes, and are made up of large calyxes and relatively few leaves. The large calyxes are very sweet and resinous, as well as extremely psychoactive. Seeds are large, shortened, flattened, and ovoid in shape with a dark grey or reddish brown, mottled perianth or seed coat. The caruncle or point of attachment at the base of the seed is uncommonly deep and usually is surrounded by a sharp edged lip. Some individuals turn a very light yellow green in the flowering clusters as they mature under exposed conditions. Although they mature relatively late, they do seem to have met with acceptance in Great Britain and North America as drug strains. Seeds of many strains appear in small batches of low-quality African marijuana easily available in Amsterdam and other European cities. Phenotypes vary considerably, however, many are similar in appearance to strains from Thailand.


i) Mexico - (15 to 27 north latitude)


Mexico had long been the major source of marijuana smoked in America until recent years. Efforts by the border patrols to stop the flow of Mexican marijuana into the United States were only minimally effective and many varieties of high quality Mexican drug Cannabis were continually available. Many of the hybrid strains grown domestic ally today originated in the mountains of Mexico. In recent years, however, the Mexican government (with monetary backing by the United States) began an intensive pro gram to eradicate Cannabis through the aerial spraying of herbicides such as Paraquat. Their program was effective, and high quality Mexican Cannabis is now rarely available. It is ironic that the NIMH (National Institute of Mental Health) is using domestic Mexican Cannabis strains grown in Mississippi as the pharmaceutical research product for chemotherapy and glaucoma patients. In the prime of Mexican marijuana cultivation from the early 1960s to the middle 1970s, strains or "brands" of Cannabis were usually affixed with the name of the state or area where they were grown. Hence names like "Chiapan," "Guerreran," "Nayarit," "Michoacan," "Oaxacan," and "Sinaloan" have geo graphic origins behind their common names and mean something to this very day. All of these areas are Pacific coastal states extending in order from Sinaloa in the north at 27; through Nayarit, Jalisco, Michoacan, Guerrero, and Oaxaca; to Chiapas in the south at 15 - All of these states stretch from the coast into the mountains where Cannabis is grown.


Strains from Michoacan, Guerrero, and Oaxaca were the most common and a few comments may be ventured about each and about Mexican strains in general.


Mexican strains are thought of as tall, upright plants of moderate to large size with light to dark green, large leaves. The leaves are made up of long, medium width, moderately serrated leaflets arranged in a circular array. The plants mature relatively early in comparison to strains from Colombia or Thailand and produce many long floral clusters with a high calyx-to-leaf ratio and highly cerebral psychoactivity. Michoacan strains tend to have very slender leaves and a very high calyx-to-leaf ratio as do Guerreran strains, but Oaxacan strains tend to be broader-leafed, often with leafier floral clusters. Oaxacan strains are generally the largest and grow vigorously, while Michoacan strains are smaller and more delicate. Guerreran strains are often short and develop long, upright lower limbs. Seeds from most Mexican strains are fairly large, ovoid, and slightly flattened with a light colored grey or brown, unmottled perianth. Smaller, darker, more mottled seeds have appeared in Mexican marijuana during recent years. This may indicate that hybridization is taking place in Mexico, possibly with introduced seed from the largest seed source in the world, Colombia. No commercial seeded Cannabis crops are free from hybridization and great variation may occur in the offspring. More recently, large amounts of hybrid domestic seed have been introduced into Mexico. It is not uncommon to find Thai and Afghani phenotypes in recent shipments of Cannabis from Mexico.

k) Nepal - (26 to 30 north latitude)


Most Cannabis in Nepal occurs in wild stands high in the Himalayan foothills (up to 3,200 meters [10,000 feet]). Little Cannabis is cultivated, and it is from select wild plants that most Nepalese hashish and marijuana originate. Nepalese plants are usually tall and thin with long, slightly branched limbs. The long, thin flowering tops are very aromatic and reminiscent of the finest fresh "temple ball" and "finger" hashish hand-rubbed from wild plants. Resin production is abundant and psychoactivity is high Few Nepalese strains have appeared in domestic Cannabis crops but they do seem to make strong hybrids with strains from domestic sources and Thailand.
m) South Africa - (22 to 35 south latitude)


Dagga of South Africa is highly acclaimed. Most seeds have been collected from marijuana shipments in Europe. Some are very early-maturing (September in northern latitudes) and sweet smelling. The stretched light green floral clusters and sweet aroma are comparable to Thai strains.


n) Southeast Asia - Cambodia, Laos, Thailand and Vietnam (10 to 20 north latitude)



Hi Bricktop,
This info is confirming what I've been telling the folk around here for a while.
....I'm not a great grower. I live in a superior growing climate. 4000ft ele in southern AZ. Air is dry and clear. UV index of 10+ most the time and very few cloudy days.




And to give some idea of how elevation increases UV-B light wave intensity .... for every 1000 meters increase in altitude UV-B radiation levels increase by 10% to 12%.
If you hiked to the top of Mount Rushmore, the UV-B levels there would be 15-18% stronger than at sea level, just from the change in altitude alone. If you climbed to the top of Mount Everest you would be looking at a 100% and greater increase in UV-B strength.

Humidity, more precisely low humidity, during the flowering stage of growth, is important, it does play a factor, it will result in shorter, stronger and thicker/more dense trichome development. High humidity will result in the opposite. Long tall trichome stalks with heads that break off easily and less dense trichome coverage of buds, leaves and along veins.
  • PureGro1, DarKwon, 0calli and 1 other like this

#14 OFFLINE   DarKwon

DarKwon

    Ganga Din

  • High Society Stoner
  • 18,504 posts

Posted 14 October 2012 - 06:48 AM

you keep adding to my contention, my friend
Humidity is pretty low here, too. 30% is high. Our temp spreads [day/night] are typically +25-30. I live in a cold air drainage, which makes it worse. 40` between day and night is not uncommon.
  • PureGro1, 0calli, RoofCraig and 1 other like this

#15 OFFLINE   Brick Top

Brick Top

    Losing Lighters

  • Inactive Stoner
  • 56 posts
  • LocationThe Confederate States of America

Posted 14 October 2012 - 11:38 AM

http://www.reptileuv...ay-products.php
  • Liveforever likes this





Similar Topics Collapse

  Topic Name Started By Stats Last Post Info

Also tagged with one or more of these keywords: uv rays, spectrums, 0calli, thc