D
dwhizzle74
Guest
do buds or leaves pick up more sunlight? i was thinkin about doing a small trim job just to get more sunlight inside to the buds but if thats not gonna help em plump up im not gonna mess with it
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The leaves are the engines that drive the buds. Some people like to selectively remove some, others like to tuck them out of the way. Personally, I just leave them.
R
roadsidevendor1
Guest
if you do decide to trim some leaf,
for whatever reason,
i recommend consuming the raw
leaf,or juicing.
raw canna leaf is chock-full of
benefits.
for whatever reason,
i recommend consuming the raw
leaf,or juicing.
raw canna leaf is chock-full of
benefits.
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Don't mess with it mate, at the very least you'll shock the plant & stall growth. I know a few people who remove leaves, and they never do any better than mine where I just tuck the leaves under.
The more leaves you remove, the less leaves you'll have after maybe having an unforeseen problem that would cause the plant to loose a few. (That's a shitty scenario, but you know how it is, anything can happen.) Take away the leaves that suck up light, or should I say, life... My : not good.
The plant thins itself out by itself towards the end. 'Cept for brown leaves or brown parts of leaves. They can go.
: not good.The plant thins itself out by itself towards the end. 'Cept for brown leaves or brown parts of leaves. They can go.
T
Trifid
Guest
This is a good question.. Shade leaves are indeed energy factories essential to all plant processes. However If studies have shown that under conditions of high UV-B (280-315 nm) exposure, cannabis produces significantly greater quantities of THC resin (Lydon, Teramura,Coffman 1987) then shade leaves may be considered more or less essential to the production of fine cannabis since shade leaves absorb light almost exclusively above 400nm having the effect of intensifying the UV-B radiation that reaches the flowers below. Removing the shade leaves (apart from depriving the plant of an essential energy source tailored to it's means) has the effect of subtracting or diluting the UV-B intensity. After-all the plant itself has put them there as directed by millions of years of evolution so it doesn't make much sense to deprive the plants of them.
[Lydon, J., A. H. Teramura and C. B. Coffman (1987) UV-B radiation effects on photosynthesis, growth and cannabinoid production of two Cannabis sativa chemotypes. Photochem. Photobiol. 46, 201-206.]
[Lydon, J., A. H. Teramura and C. B. Coffman (1987) UV-B radiation effects on photosynthesis, growth and cannabinoid production of two Cannabis sativa chemotypes. Photochem. Photobiol. 46, 201-206.]
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M
mattinuk3
Guest
You know something? Some of my photoperiods are more resinous indoor than they were outdoor. Do you think the hydroponics cause the resin difference (just the simple fact that they're in a perfect environment), or is it the uv light from the led? Do the blackstar leds emit more uv than sunlight?
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T
Trifid
Guest
That's another good question. I'm sure others might be able to give some input here also. I don't use LED's but i know they are capable of emitting a variety of wavelengths throughout the color spectrum. Those that emit light toward the blue end of the spectrum ( 450 < λ < 500) such as Zinc selenide (ZnSe), Indium gallium nitride (InGaN), Silicon carbide (SiC) as substrate are closest to the UV region. The real factor influencing the efficiency of LED related to resin production is likely to arise from the fact that the light emission cones of an LED wafer are far more complex than a single point-source light emission. The light emission zone is typically a two-dimensional plane between the wafers whereby each atom across this plane has an individual set of emission cones.
In reply to your question and reference to other environmental factors that may influence resin production, another study (sorry i have no reference for this) suggested a positive correlation to THC secretion and low humidity since it appears that one of the purposes of glandular trichomes is to protect the plant from desiccation. The sticky oil coats the flora and portions of the leaves and protects the plant from becoming too dry, (similar to the way waxy cacti protect themselves).
It's also interesting to note that the evolution of cannabis has spread throughout Indo-China, India, Arabia, Moroco, Afghanistan, all arid dry areas. Most of the best strains are naturally grown in dry arid climates with high levels of UV-B exposure..
In reply to your question and reference to other environmental factors that may influence resin production, another study (sorry i have no reference for this) suggested a positive correlation to THC secretion and low humidity since it appears that one of the purposes of glandular trichomes is to protect the plant from desiccation. The sticky oil coats the flora and portions of the leaves and protects the plant from becoming too dry, (similar to the way waxy cacti protect themselves).
It's also interesting to note that the evolution of cannabis has spread throughout Indo-China, India, Arabia, Moroco, Afghanistan, all arid dry areas. Most of the best strains are naturally grown in dry arid climates with high levels of UV-B exposure..
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M
marclar
Guest
does the uva/uvb spectrum difference matter much?
if your growing indoor can you use a 'reptile & plant' UV supplement bulb such as:
http://www.ebay.com/itm/New-Double-...957?pt=LH_DefaultDomain_0&hash=item415fe73ffd
if your growing indoor can you use a 'reptile & plant' UV supplement bulb such as:
http://www.ebay.com/itm/New-Double-...957?pt=LH_DefaultDomain_0&hash=item415fe73ffd
T
Trifid
Guest
Marclar.. To answer your question - Plants and plant flora are particularly sensitive to UV-B exposure. Standard UV emittance of a compact florescence lamp is approximately 10% UV-B and 30% UV-A. Investigations of UV effects on plant physiology have largely depended on the use of UV-B emitting lamps in both laboratory and field settings - Tevini (1994) and Bornman; Teramura (1993). Interpretation of results however, is confined by an inability to mimic the solar spectrum precisely - as a consequence, comparisons between species with respect to UV-B sensitivity, and analyses of processes responsible for variation in sensitivity, have to be treated circumspectly. Despite these methodological limitations, overall outcomes are unambiguous: UV-B radiation impacts on many aspects of plant biology and in particular the bio-synthesis of various phytohormones and alkaloids.
Many significant effects have been observed for about 60% of the 1000 or so cultivars studied so far, but with some notable variation. UV-B sensitivity is perhaps most noticeable with regard to alterations in plant growth and development (Teramura 1983) these include a reduction in leaf area, internodal spacing and total plant biomass. Growth reductions during vegetative phases depend not only on the level of UV-B exposure but on the associated level of photosynthetic active radiation. Intrinsic susceptibility can vary within a crop species among a series of pheno and geno-types, with the most significant differences noted by Teramura and Murali (1986). Partitioning of growth to different tissues, for example altered internode length, or leaf production, is closely related to UV-B exposure during vegetative phase (Teramura 1983). Such morphological changes may not be significant to plants in isolation but may influence competitive interactions between neighboring plants, and especially their competition for exposure. Thus sensitivity to UV-B irradiation varies with life cycle whereby seedlings are especially vulnerable, as are mature plants under-going their transition from vegetative growth to reproductive development (Teramura and Sullivan 1987).
In general, UV-B radiation causes a net inhibition of photosynthesis in a wide range of plants (see Tevini 1993). From laboratory studies, this inhibition appears to arise from disruptions at a number of points in the photosynthetic cycle including disruption of PSII reaction centres (Strid et al. 1990), a decrease in Rubisco activity and damage to photosynthetic pigments (chlorophylls and carotenoids). Stomatal function, and thus leaf gas exchange, is also commonly impaired (Teramura 1983; Tevini and Teramura 1989).
Alterations in plant growth induced by UV-B radiation have been partly attributed to changes in nucleic acid structure and function (Beggs et al. 1986; Tevini 1994). DNA absorbs strongly in the UV region and is thus especially prone to damage by UV-B radiation (Figure 12.17). The most common lesions are breaks in DNA chains, with a resultant production of thymine dimers. They in turn interfere with accurate base pairing, leading to a disruption of transcription and replication of DNA (Stapleton 1992). These disruptions amount to a mutagenic action for UV radiation in many organisms. Proteins and RNA can also absorb UV-B and are inactivated as a result, but this loss is of secondary importance due to their relative abundance compared with DNA (Stapleton 1992).
Activation and photo-deactivation of various important signal molecules are also sensitive effects of UV-B irradiation on plant growth and development. For instance, cell extension in many plants is influenced by indole acetic acid (a powerful growth promoter) which absorbs in the UV-B region and is photo-oxidised to 3-methyleneoxindole, an inhibitor of hypocotyl growth when exogenously applied (Tevini and Teramura 1989). In contrast, irradiation with UV-B can induce enzyme activity in the shikimic acid pathway, which regulates the synthesis of a broad array of plant compounds ranging from flavonoids to lignin, all of which are important to plant function, including tolerance to UV-B radiation (Caldwell et al. 1989).
Many organisms have evolved to tolerate the molecular morphologies caused by UV radiation. Possibly the most adaptive are terrestrial plants that rely on full sunlight for photosynthesis -protective mechanisms can be classified into two main classes: (1) those whereby UV damage is repaired or its effects negated or minimised, and (2) those whereby the amount of UV radiation actually reaching sensitive areas is reduced. While protective in nature, all of these mechanisms impose an energy cost on plants so adapted.
As mentioned above, plant growth and development is slowed by exposure to enhanced UV-B radiation, and especially in sensitive plants. Ironically, such delay also minimises adverse effects from damage that has occurred. Growth delay and slower cell division provides additional time for DNA repair mechanisms to operate ahead of any recommencement in DNA replication (Beggs et al. 1986).
The use of UV-B is to be taken with caution - there are some dangers involved with human UV exposure in particular UV-A since it is profoundly carcinogenic. Clearly there are both advantages and disadvantages to UV-B exposure in plants relative to their development and productivity. Thus the over-exposure or the use UV-B supplementation for increasing crop productivity is perhaps unjustified and possibly detrimental. Never-the-less some cannabis cultivators continue to impliment UV-B supplimentaion in their grow spaces. A colleague from my institution where we grow tobbacco plants under intense UV-B exposure for the production of micellar-biocides for anti-viral agents uses 10,000K Sunpulse lamps on his crop plants for the last three weeks of flowering.
UV-B exposed Dutch-Passion blueberry
- From my experience, I'd say the product derived from supplementation is no more abundant in trichomes than that produced under standard conditions.
Many significant effects have been observed for about 60% of the 1000 or so cultivars studied so far, but with some notable variation. UV-B sensitivity is perhaps most noticeable with regard to alterations in plant growth and development (Teramura 1983) these include a reduction in leaf area, internodal spacing and total plant biomass. Growth reductions during vegetative phases depend not only on the level of UV-B exposure but on the associated level of photosynthetic active radiation. Intrinsic susceptibility can vary within a crop species among a series of pheno and geno-types, with the most significant differences noted by Teramura and Murali (1986). Partitioning of growth to different tissues, for example altered internode length, or leaf production, is closely related to UV-B exposure during vegetative phase (Teramura 1983). Such morphological changes may not be significant to plants in isolation but may influence competitive interactions between neighboring plants, and especially their competition for exposure. Thus sensitivity to UV-B irradiation varies with life cycle whereby seedlings are especially vulnerable, as are mature plants under-going their transition from vegetative growth to reproductive development (Teramura and Sullivan 1987).
In general, UV-B radiation causes a net inhibition of photosynthesis in a wide range of plants (see Tevini 1993). From laboratory studies, this inhibition appears to arise from disruptions at a number of points in the photosynthetic cycle including disruption of PSII reaction centres (Strid et al. 1990), a decrease in Rubisco activity and damage to photosynthetic pigments (chlorophylls and carotenoids). Stomatal function, and thus leaf gas exchange, is also commonly impaired (Teramura 1983; Tevini and Teramura 1989).
Alterations in plant growth induced by UV-B radiation have been partly attributed to changes in nucleic acid structure and function (Beggs et al. 1986; Tevini 1994). DNA absorbs strongly in the UV region and is thus especially prone to damage by UV-B radiation (Figure 12.17). The most common lesions are breaks in DNA chains, with a resultant production of thymine dimers. They in turn interfere with accurate base pairing, leading to a disruption of transcription and replication of DNA (Stapleton 1992). These disruptions amount to a mutagenic action for UV radiation in many organisms. Proteins and RNA can also absorb UV-B and are inactivated as a result, but this loss is of secondary importance due to their relative abundance compared with DNA (Stapleton 1992).
Activation and photo-deactivation of various important signal molecules are also sensitive effects of UV-B irradiation on plant growth and development. For instance, cell extension in many plants is influenced by indole acetic acid (a powerful growth promoter) which absorbs in the UV-B region and is photo-oxidised to 3-methyleneoxindole, an inhibitor of hypocotyl growth when exogenously applied (Tevini and Teramura 1989). In contrast, irradiation with UV-B can induce enzyme activity in the shikimic acid pathway, which regulates the synthesis of a broad array of plant compounds ranging from flavonoids to lignin, all of which are important to plant function, including tolerance to UV-B radiation (Caldwell et al. 1989).
Many organisms have evolved to tolerate the molecular morphologies caused by UV radiation. Possibly the most adaptive are terrestrial plants that rely on full sunlight for photosynthesis -protective mechanisms can be classified into two main classes: (1) those whereby UV damage is repaired or its effects negated or minimised, and (2) those whereby the amount of UV radiation actually reaching sensitive areas is reduced. While protective in nature, all of these mechanisms impose an energy cost on plants so adapted.
As mentioned above, plant growth and development is slowed by exposure to enhanced UV-B radiation, and especially in sensitive plants. Ironically, such delay also minimises adverse effects from damage that has occurred. Growth delay and slower cell division provides additional time for DNA repair mechanisms to operate ahead of any recommencement in DNA replication (Beggs et al. 1986).
The use of UV-B is to be taken with caution - there are some dangers involved with human UV exposure in particular UV-A since it is profoundly carcinogenic. Clearly there are both advantages and disadvantages to UV-B exposure in plants relative to their development and productivity. Thus the over-exposure or the use UV-B supplementation for increasing crop productivity is perhaps unjustified and possibly detrimental. Never-the-less some cannabis cultivators continue to impliment UV-B supplimentaion in their grow spaces. A colleague from my institution where we grow tobbacco plants under intense UV-B exposure for the production of micellar-biocides for anti-viral agents uses 10,000K Sunpulse lamps on his crop plants for the last three weeks of flowering.
UV-B exposed Dutch-Passion blueberry
- From my experience, I'd say the product derived from supplementation is no more abundant in trichomes than that produced under standard conditions.
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