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A blog by HC01
HARDCORE CANNABIS
First I would like to thank Green House Seeds, a seed to make the best
Franco and Fuzzy for trusting me and put me on the list of Tester.
And the moderators Romeo and Dusty for support.
It's my first test, and I'm here to learn and not to teach
for so I can fix any errors.
But is not my first crop, already growing sativas South American strains.
Peace to all!
By HC01,
EFFECT OF LIGHT QUALITY ON CANNABINOID CONTENT
OF CANNABIS SATIVA L. (CANNABACEAE)
PAUL G. MAHLBERG AND JOHN K. HEMPHILL
Department of Biology, Indiana University, Bloomington, Indiana 47405
Plants of a drug strain of Cannabis sativa L.-grown 33 days under daylight, shaded daylight
conditions, filtered green, blue, and red light, and darkness---were analyzed by gas-liquid chromatography
for their cannabinoid content. The highest content of cannabinoids, predominantly áƒ9- tetrahydrocannabinol
(áƒ9-THC) in this strain, occurred in the youngest leaves of daylight-grown plants.
Leaves at successively lower nades of this contrai condition and ali treated plants subsequently grown’
in daylight contained progressively lower leveis of cannabinoids. Leaves from plants grown under
filtered green light and darkness contained significantly lower leveis of áƒ9-THC than those from plants
grown in daylight. However, the áƒ9-THC content of leaves from plants grown under shaded daylight
and filtered red and blue light did not differ significantly from the áƒ9-THC content in daylight contrais,
indicating that these conditions did not a! ter the synthetic rate of this cannabinoid. The cannabichromene
(CBC) content of plants grown under filtered red and green light and darkness differed from the
CBC content in plants grown in daylight, indicating that the formation of this cannabinoid was
independent of áƒ9-THC. Leaves from plants grown under filtered red and green light and darkness
recovered the capacity to synthesize typicallevels of áƒ9-THC and CBC when placed under daylight
conditions. Plants from ali light and dark treatments, when subsequently placed under daylight conditions
for 66 days, attained leveis of cannabinoid synthesis comparable to the daylight contrais.
Introduction
Both qualitative and quantitative variability in cannabinoid composition among numerous vari eties of Cannabis have been reported (SMALL and BECKSTEAD 1973; TURNER et al. 1975; HEMPHILL, TURNER, and MAHLBERG 1980). Aside from arti factual differences induced by sampling techniques (FAIRBAIRN and LIEBMANN 197 4; TURNER, HEMP HILL, and MAHLBERG 1977, 1978), the factors con trolling the cannabinoid profile in plants are only partially understood. Both genetic and environ mental infl.uences probably contribute to their can nabinoid composition. The effects of light and, in a broader relationship, of the photosynthetic ap paratus on cannabinoid production are incom pletely understood. CROMBIE (1977) reported that albino and green tissues on green plants contained cannabinoids. Green plants placed in the dark continued to possess cannabinoids (FAIRBAIRN and LIEBMANN 197 4; HEMPHILL, TURNER, and MAHLBERG, unpublished). VALLE et al. (1978) sug gested that photoperiod can infl.uence cannabinoid content in that increased daylength increased the tetrahydrocannabinol content in plants. Cyclic or rhythmic changes in cannabinoid content in plants have been reported to occur in which A•-tetrahy drocannabinol (áƒ9-THC) content varied through out the growing season in comparison with that for other cannabinoids (PHILLIPS et al. 1970; TURNER et al. 1975), although LANYON et al. (forthcoming) could not detect any rhythmic pattern for the prouction of cannabinoids in an in-depth 2-yr study of three clones.
The purpose of this study was to determine the effects of light quality on cannabinoid composition of C annabis. Plant populations of a Mexican drug strain were used and examined periodically during a growth period under daylight, filtered red, blue, and green light, and darkness to assess the infl.uence of light quality on cannabinoid formation.
Material and Methods
Plants of a Mexican drug strain of Cannabis Sativa L. (HAMMOND and MAHLBERG 1977, 1978) were grown from seed in a greenhouse in a uniform
soil mixture in peat pots maintained in flats, each containing ca. 50 plants. Plants were grown under different light treatments, including daylight, two conditions of shaded daylight, green, blue, and red filtered light, and darkness (tables 1, 2). For day light conditions, flats were maintained on a green house bench; the two shaded conditions were prepared by covering a frame around the flats with multiple layers of cheesecloth, which shaded plants to selected light levels. Green, blue, and red con ditions were established by placing flats under cu bic chambers, 30 inches on each side, made from Rohm and Haas Plexiglas (green, no. 2092; blue, no. 2045; red, no. 2444) that possesses spectral properties applicable in wavelength studies (RAG HAVAN 1973; GALSTON and SATTER 1974). Each filter chamber was placed over a 30-inch central opening in a light-tight wooden base, 48 inches square X 6 inches high. The base, open at the bottom, was placed on the gravel bed of a green house bench. Air circulation in these chambers was
provided by two light-baffled 4-inch ports in the base. A 3-inch fan was mounted in one port and was in continuous operation during the experi ments. All flats were watered from the exterior and received measured volumes of water periodically, All plants and chambers were maintained in an air-conditioned greenhouse with temperatures ranging between 20 and 30 C during the experi ments. Plants grown in chambers were never ex posed to white light. Plants grown in the dark were maintained in similar chambers covered with black cardboard and placed in a shaded area of the green house.Light level in the greenhouse at noon during spring on a sunny day measured an average of
1.5 x 105 ergs em-' s- • with the thermistor shaded from direct sunlight (YSI-Kettering Radiometer, model 65). The two shaded conditions averaged
4. 0 X 104 (condition A) and 3.2 X 104 (condition b ergs cm-2 s-•. Light level at noon under green, blue, and red light was adjusted to a similar level,
5. 5 X 104 ergs em-' s-•, with one or two 200-W incandescent bulbs suspended over the chambers. These bulbs were on from 10:00 A.M. to 2:00 P.M. to supplement normal daylight.
Leaves or shoot tips from ca. 10 plants in each treatment were harvested at night under dim green light after 33, 66, and 99 days of growth. All treat ments at these times were sampled the same night without exposing the plants to white light. Har vested tissues were immediately oven dried at 60
C for 12- 14 h. Dried tissues for each sample in each treatment were randomly divided into threelots, except that only one sample was available for green, blue, and red treatments at the 33-day interval.
All samples were extracted for analyses of cannabinoids by gas-liquid chromatography (HEMPHILL et al. 1980). Each datum value in the tables
represents the mean from analyses of the three lots for each sample, except where indicated below.
The remaining plants after the 33-day treatment were removed from the chambers and maintained under ambient daylight conditions along with daylight
controls. Leaf samples from specific nodes (tables 2--4) of several to 10 plants were collected again after 66 and 99 days of growth (33 and 66days in daylight, respectively, for plants from chambers). Leaf samples were collected and analyzedas described above.
This experimental study was repeated three times during a 2-yr period. Data presented in this report represent those derived from the third study; however,
data and trends for cannabinoids were similar in the several studies. The t-test was used to examine significance of áƒ9-THC and total cannabinoids
in tables 1 and 2.
Voucher specimens of several ages of the Mexican strain of C. sativa are deposited in the departmental herbarium.
Results
The cannabinoid content of 33-day-old plants grown in daylight possessed a characteristic distribution of cannabinoids for leaves along the vegetative
axis (HEMPHILL et al. 1980). The youngest leaves at node 1 (N- 1) contained the highest concentration of áƒ9-THC (2. 24 mg/ 100 mg dry weight
[DW]), as well as lower concentrations of cannabichromene (CBC), cannabidiol (CBD), and cannabinol (CBN) (table 1). Older leaves on subjacent
nodes (N-2 through N-5) contained progressively lower concentrations of áƒ9-THC and other cannabinoids.In plants grown for 33 days under different light
conditions, those grown under daylight contained an average of 0. 77 mg áƒ9-THC/ 100 mg DW tissues (table 2). This value represented the average content
for leaves from all nodes, N- 1 through N-5 (table 1). The youngest leaves on the daylight control plants (N- 1 and N-2) contained considerably
greater quantities of áƒ9-THC (2. 24 mg and 0. 95 mg/100 mg DW, respectively) than leaves on lower
nodes. The average value of Ll 9-THC for daylight controls was compared with the total Ll 9 -THC con tent for other experimental conditions because it was not possible to distinguish among leaf nodes on plants under ali treatments at the end of 33 days. Partia! shading of plants grown in daylight (shaded A, 0.41 mg Ll áƒ9-THC; shaded B, 0.33 mg Ll áƒ9-THC) resulted in a trend toward a decreased cannabinoid content (table 2). Young leaves (N-1) of daylight plants had a significantly greater quan tity of cannabinoids (as Ll áƒ9 -THC) than shaded plants, but when the average (O. 77 mg Ll áƒ9-THC) was compared withLl áƒ9 -THC content in shaded plants, there was no significant difference for this
cannabinoid between these sets of plants.
The cannabinoid concentrations in plants grown 33 days under filtered light and in the dark showed a trend toward a lower concentration of Ll áƒ9-THC compared with the daylight controls. The Ll áƒ9-THC content in the top node of the daylight control was significantly greater than the content in leaves from ali filter treatments as weli as for plants grown in darkness. However, the average Ll áƒ9-THC content in the daylight controls did not differ significantly from leveis present in plants grown under red and blue filtered light.
The levei of CBC, another prominent cannabi noid in this strain, remained comparable to day light controls under most treatments, including those plants grown in the dark. Under red filtered light, the plants contained over twice the levei (0.69 mg) of CBC present in the daylight controls (0.30 mg). Under daylight and shaded daylight conditions, the Ll áƒ9-THC content always exceeded the CBC con tent. However, the ratio of CBC to Ll áƒ9-THC be came reversed under ali filtered light and dark conditions. A relatively high levei of CBC, but very low levei of Ll áƒ9-THC, occurred in plants grown in the dark (table 2).
Leaf tissue of plants from ali treatments, after being placed in daylight for 33 days, was coliected and analyzed for cannabinoid composition to de termine whether treated plants could recover from imposed light-stress conditions (table 3). Sufficient
leaf material had developed on all plants during the 33 days of growth in daylight to make it possible to analyze leaves from three nodal positions: young leaves from nodes near apex (table 3, sample 1), leaves from subjacent middle nodes (sample 2), and leaves from lower nodes (sample 3).
Total cannabinoid and /áƒ9-THC content in young leaves (sample 1) contained increased levels for these compounds in all treatments (cf. tables 2, 3). Plants derived from red and blue light treatments showed a trend toward higher total levels of cannabinoids than daylight-grown plants, while those from green light and shaded B conditions contained lower cannabinoid levels than other treatments (table 3, sample 1). Samples 2 and 3 contained progressively lower cannabinoid and /áƒ9-THC levels under all treatments, a trend consistent for plants grown under daylight conditions (table 3, samples 2 and 3). CBD and CBN synthesis are typically low in this strain. However, for plants grown under blue filters and in darkness, no CBD was detectable, while plants grown under red filters synthesized appreciably greater quantities of both CBD and CBN than other treatments (table 3, sample 1).
Sample 3 for plants originally under filters and in the dark represented leaves that had formed during the first 33 days of treatment and subsequently enlarged when exposed to daylight for the second 33-day growth period. Some /áƒ9-THC synthesis occurred in these leaves upon exposure to light during this second growth period since the CBC to /áƒ9-THC ratio, greater than 1.0 in filterand dark-treated plants (table 2), was restored to the more typical less than 1.0 ratio (table 3, sample3).
Plants were maintained for 66 days in daylight (99 days of total growth) and again analyzed for cannabinoid contents to determine whether plants after an extended growth period in daylight developed a pattern of cannabinoid synthesis comparable to daylight-grown plants. Sufficient new growth had occurred on plants during their 99-day growth period to provide leaf materials from different nodal positions for analysis (table 4).
Leaves from nodal regions at three different levels along the axis, including those from N-1-3, N-7-9, and N- 17- 19 (table 4), were sampled for cannabinoid composition. Plants transferred to daylight from the dark remained somewhat smaller than other plants, and leaf samples were derived from nodal positions indicated in table 4. The total cannabinoid and áƒ9-THC contents in young leaves (N-1-3) in most treatments were similar (no significant differences) and were also similar to these values for plants in table 3. Plants transferred to daylight from blue filter treatment and darkness contained somewhat lower cannabinoid levels than those from other treatments.
The cannabinoid contents for daylight-grown plants (3. 48 mg áƒ9-THC and 4.99 mg total, table 4) are comparable, within the range of sample variation, to the contents of N- 1, N-2, and N-3 of young plants grown in daylight (3.66 mg áƒ9-THC and 5. 94 mg total, table 1). CBD, in blue filtered light and dark treatments
remained undetectable in plants subsequently grown for 66 and 99 days in daylight (tables 3, 4). The CBD concentration decreased in plants previously grown under green filters as well as in daylight after a total growth period of 99 days (table 4). Factors contributing to this altered CBD content remain unknown.
Discussion
Results from this study show that light quality and quantity affect cannabinoid synthesis in the growing plant. The effects were evident on the concentration of the principal cannabinoid component (áƒ9-THC) of this strain, although other cannabinoids, particularly CBC, also were influenced by light. Cannabinoid content decreased progressively and rapidly with aging of leaves for plants grown 33 days under experimental conditions. The áƒ9-THC content of the youngest leaves in the daylight controls was significantly greater than for young leaves of treated plants. However, when the average áƒ9-THC content of the control was compared to treated plants, no significant differences were evident among most treatments. Only under green filtered light was cannabinoid synthesis significantly reduced (0. 05 level) over controls. Decreased light level may reduce the pool of precursor substrates available for cannabinoid synthesis. The factors influencing the progressive decrease in cannabinoid content in successively older leaves for all treatments, as shown here and reported in other studies (HEMPHILL et al. 1980; TURNER, HEMPHILL, and MAHLBERG 1980), require further study.
Presence of cannabinoids in plants grown in darkness indicated that their synthesis can occur in the absence of light since mature nongerminated seeds of this strain lack detectable cannabinoids (HEMPHILL et al. 1980). Substrates for cannabinoid synthesis in leaves apparently were derived from seed storage materials. CBC was the most prominent component in dark-grown plants, whereas áƒ9-THC was the only other detected cannabinoid. Synthesis of áƒ9-THC in darkness, although very low, indicates that light is not essential for formation of this cannabinoid. Synthesis of cannabinoids occurred under each light condition in this study. Accumulation of a high level of CBC, in particular, resulted in an altered ratio between this cannabinoid and áƒ9-THC in plants under green, blue, and red filtered light as well as darkness. The synthesis of each of these cannabinoids is independent of that of any other, which supports the interpretation that they represent products of an alternate pathway derived from cannabigerol (CBG) (MECHOULAM 1973; SHOYAMA et al. 1975). The pathway leading to CBC is little affected by the presence or absence of light, although the enhancement noted for filtered red light requires further study. The significant reduction of áƒ9-THC under filtered green light and in the dark indicates an active, but imprecisely known, role for light in áƒ9-THC synthesis. New leaves that developed on all plants after 33 and 66 days under daylight conditions, following their transfer from filtered light treatment, synthesized cannabinoids in a pattern typical for leaves grown in daylight. Only plants grown previously under the blue filter and in darkness did not appear to attain levels of áƒ9-THC synthesis recorded for other treatments. In general, the leaves at different nodal levels showed the typical decreasing trend for each cannabinoid and their total content from young to maturing leaves. Young leaves, originally formed under filtered light and darkness and then exposed to daylight, retained the metabolic mechanism to synthesize typical levels of cannabinoids even during the protracted period of stress treatment. Leaves initiated under filtered light conditions and darkness and subsequently exposed to daylight increased their áƒ9-THC content and altered the ratio of áƒ9-THC to CBC so as to reflect the typical levels of cannabinoids present in leaves developed under daylight conditions.
Light quality influenced the ratio of CBC to áƒ9- THC accumulation in leaves. The high ratio of CBC to áƒ9-THC under filtered light conditions and the very high ratio for dark-grown plants indicated that the CBC pathway functioned under lightstressed conditions. CBC production was maintained at comparable or greater levels than those in daylight and shaded conditions. Importantly, these same leaves, when exposed to white light, were capable of d9-THC synthesis, resulting in the reversal of the CBC:áƒ9-THC ratio. Synthesis and accumulation of áƒ9-THC, therefore, can occur independently of these processes for CBC. V ALLE et al. ( 1978) also reported a change in the ratio for these cannabinoids in plants grown under different daylength conditions. The change in ratio between 33 and 66 days of daylight may be a reflection, in part, of increased day length under greenhouse conditions during our study. However, the basis for the differential between plants formerly grown in the dark ( 1:7) and those grown in daylight ( 1:3.5) after 66 days in daylight may relate to a more direct effect of the presence or absence of light. Thus, the mechanism for cannabinoid synthesis can be partially inactivated in light-stressed leaves but can be reactivated when such leaves are placed in daylight, resulting in the production of a cannabinoid profile characteristic of the plant strain.
The protoplasmic site of cannabinoid synthesis, as yet unknown, is under study at this time.
Full Archive: Effect of Light Quality on Cannabinoid Content of Cannabis sativa L.(Cannabaceae)
Good reading.
Peace.
Source: Effect of Light Quality on Cannabinoid Content of Cannabis sativa L. (Cannabaceae)
Source: WHEN WE GROW, This is what we can do (Full Documentary)
L.S.D.
Strain: L.S.D.
Breeder: Barneys Farm
Location: Indoor, Outdoor
Type: Mostly Indica
Flowering: 60/65 days
Yield: Optimum Indoor. 600 gr/m²
Indoor Height: 50 - 60 cm
Outdoor harvest time: Mid September
Ideal Pot Size: 5 Litres
THC: 24 %
CBD: 1.3 %
PEACE.
Source: *HC01* Grow Area - L.S.D.
Big Surprise, of the Green House Seeds Co.
17/05/2012
Today birthday eve, I could not get a bigger surprise, early in the morning.
I just have to thank all, just do the tests of the best seeds of the world have I'm grateful to Green House Seeds Co.
Thank you very much Arjan, Franco, Admin (H), Fuzzy, I do not have words except these,
thanks so much, I will dedicate myself more to do tests and make a contribution to the Strain Hunters Forum,
you can be absolutely sure here is my second home now.
Thank you, my great friend Scorro, who teaches me a lot to every conversation with him is a teaching.
Many thanks to my great friends Romeo and Dust, really true support always
answers very wise and direct their great support techniques are very important.
Thank you very much Green House Seeds Co. for giving me great happiness
Source: HC01 - CABOOSE - LIVE - TEST
