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Cannabis biochemistry
- Thread starter BullDogUK
- Start date
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willyweed
will take anything you have to offer .lol put it up, could look at weed pics all day every day.willyweed
Haha cheers man 
I'm thinking you meant pulling fan leaves? I'm all for it if you're doing it a few days/10 days (maybe?) before harvest to help with flushing neuts but otherwise you're only cutting down on your plant's sugar production. Obviously if a big leaf is blocking the light getting to a cola then pull the damn thing off, otherwise let the plant be
I'm thinking the next couple of posts will be on the photosynthesis pathways and a bit more advanced genetics. Mendelian genetics is all well and good, but when you're looking at crossing complete phenotypes, things get a bit complex than AaxAa = AA Aa Aa aa...
I'm thinking you meant pulling fan leaves? I'm all for it if you're doing it a few days/10 days (maybe?) before harvest to help with flushing neuts but otherwise you're only cutting down on your plant's sugar production. Obviously if a big leaf is blocking the light getting to a cola then pull the damn thing off, otherwise let the plant be
I'm thinking the next couple of posts will be on the photosynthesis pathways and a bit more advanced genetics. Mendelian genetics is all well and good, but when you're looking at crossing complete phenotypes, things get a bit complex than AaxAa = AA Aa Aa aa...
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willyweed
you are correct,in my dwc the plants have more access to more food and grow too many massive leaves,they have to go,check out my pics of one plant, biggest thing i ever grew between 8-9 dry plucked leaves all the way through,just not to many at a time.works for me.also i read somewhere plants can produce more leaves than it needs,and also in nature the plants suffer bugs eating the leaves and chewing on the roots !!! dam bugs
How are cannabinoids made? pt.1
How are cannabinoids made? pt.1
Hello everyone and welcome back!
University is over so I finally have some time to put into doing this!
So I've decided it'd be cool if we could investigate how cannabinoids are produced in the plant, what sort of factors affect this synthesis and how/why.
As you, hopefully - being in the advanced botany forum, know photosynthesis is the process by which atmospheric CO2 is captured by a plant and converted into sugars via the light independent Calvin cycle.
This cycle leads to the net production of 1 G3P molecules every three 'turns' of the cycle. Two of these molecules can then be combined to form glucose which is the base molecule in carbohydrate synthesis and energy production. Though it is considered to be light independent, without the process of photosynthesis occuring, the required NADPH and ATP rapidly runs out and brings the process to a halt. This process of carbon fixing is how the majority of carbon we see today accumulated in biomass is formed. Trees, for example, are made mostly out of atmospheric CO2, not minerals they've sucked up from the ground.
Now, as this is the main source of a plant's energy, we'd expect more light to equate with a greater yield - the rough equivalent of fattening up an animal before butchering them. What we find though is that this is not necessarily the case.
We can see from this study (Bazzaz et al., 1975, Photosynthesis and Cannabinoid Content of Temperate and Tropical Populations of Cannabis sativa) that the initial growing conditions of the cannabis plant can have a large impact on the highest possible photosynthetic rates; we see that the population of plants grown in 'cool' conditions were not able to reach the same levels of photosynthesis as those grown in the 'warm' chamber when measured at the same temperature. This suggests that the initial environmental factors present during the plant's development can steer a course of gene activation/deactivation which persist throughout it's life cycle. It's conceivable that these epigenetic changes would also persist in clones taken from these plants.
Perhaps the most bizarre feature of this study was the investigation of cannabinoid production in these plants. We see that the typical 'tropical'/'non-tropical' (Sativa/Indica?) categories have no real holding over the cannabinoid production rates. What's really noticeable is just how variable these rates are and how little bearing they have on whether a plant is growing within a 'natural' environment for that particular landrace. This suggests to me that cannabinoid production is likely related to a large number of genes which may be sensitive to environmental factors. The tripling in THC production of Jamaican landraces grown in cool conditions compared to warm conditions shows that perhaps exposure to stress could trigger greater THC synthesis though the high levels of THC in the Nepalese landrace in it's 'natural' setting sort of refutes this.
Anyways hope y'all enjoyed this and thanks for reading
How are cannabinoids made? pt.1
Hello everyone and welcome back!
University is over so I finally have some time to put into doing this!
So I've decided it'd be cool if we could investigate how cannabinoids are produced in the plant, what sort of factors affect this synthesis and how/why.
As you, hopefully - being in the advanced botany forum, know photosynthesis is the process by which atmospheric CO2 is captured by a plant and converted into sugars via the light independent Calvin cycle.
This cycle leads to the net production of 1 G3P molecules every three 'turns' of the cycle. Two of these molecules can then be combined to form glucose which is the base molecule in carbohydrate synthesis and energy production. Though it is considered to be light independent, without the process of photosynthesis occuring, the required NADPH and ATP rapidly runs out and brings the process to a halt. This process of carbon fixing is how the majority of carbon we see today accumulated in biomass is formed. Trees, for example, are made mostly out of atmospheric CO2, not minerals they've sucked up from the ground.
Now, as this is the main source of a plant's energy, we'd expect more light to equate with a greater yield - the rough equivalent of fattening up an animal before butchering them. What we find though is that this is not necessarily the case.
We can see from this study (Bazzaz et al., 1975, Photosynthesis and Cannabinoid Content of Temperate and Tropical Populations of Cannabis sativa) that the initial growing conditions of the cannabis plant can have a large impact on the highest possible photosynthetic rates; we see that the population of plants grown in 'cool' conditions were not able to reach the same levels of photosynthesis as those grown in the 'warm' chamber when measured at the same temperature. This suggests that the initial environmental factors present during the plant's development can steer a course of gene activation/deactivation which persist throughout it's life cycle. It's conceivable that these epigenetic changes would also persist in clones taken from these plants.
Perhaps the most bizarre feature of this study was the investigation of cannabinoid production in these plants. We see that the typical 'tropical'/'non-tropical' (Sativa/Indica?) categories have no real holding over the cannabinoid production rates. What's really noticeable is just how variable these rates are and how little bearing they have on whether a plant is growing within a 'natural' environment for that particular landrace. This suggests to me that cannabinoid production is likely related to a large number of genes which may be sensitive to environmental factors. The tripling in THC production of Jamaican landraces grown in cool conditions compared to warm conditions shows that perhaps exposure to stress could trigger greater THC synthesis though the high levels of THC in the Nepalese landrace in it's 'natural' setting sort of refutes this.
Anyways hope y'all enjoyed this and thanks for reading
Dingofriar
Member
Been a minute since I stuck my nose in here. But great info still. Good luck on your summer vac/studies. Be safe brother!
So the cool chamber varies between 15 and 30, the warmer one between 20-30?
I couldn;t make sence of that graph
I couldn;t make sence of that graph
'Cannabis satire seeds were collected from mature
plants in east central Illinois, near the coast in Panama,
at about 2000 ft elevation in central Jamaica, and at
about 6000 ft near Katmandu, Nepal.
Seeds from these localities were sown in loam-filled
8-in, clay-pots incubated at 22 ° for 11 days and then
transferred to two growth chambers when the seedlings
were about 4 cm tall. The growth chambers were
programmed to approximate tropical and temperate
temperatures. The temperature of the "warm chamber'"
was 32 ° during the day and 23 ° at night, while that of
the cool chamber was 23 ° and 16°; day length was 15hr.
Light intensity, generated by 16 cool white fluorescent
and eight 25W incandescent lamps was approximately
40 000 lux near the top of the plants. Since Cannabis is a
dioecious species and there may be differences
between male and female plants, only mature yet
sexually undifferentiated plants were used for all
measurements. ' Extract from the paper.
plants in east central Illinois, near the coast in Panama,
at about 2000 ft elevation in central Jamaica, and at
about 6000 ft near Katmandu, Nepal.
Seeds from these localities were sown in loam-filled
8-in, clay-pots incubated at 22 ° for 11 days and then
transferred to two growth chambers when the seedlings
were about 4 cm tall. The growth chambers were
programmed to approximate tropical and temperate
temperatures. The temperature of the "warm chamber'"
was 32 ° during the day and 23 ° at night, while that of
the cool chamber was 23 ° and 16°; day length was 15hr.
Light intensity, generated by 16 cool white fluorescent
and eight 25W incandescent lamps was approximately
40 000 lux near the top of the plants. Since Cannabis is a
dioecious species and there may be differences
between male and female plants, only mature yet
sexually undifferentiated plants were used for all
measurements. ' Extract from the paper.
I would have thought that the very definition of epigenetic effects meant that they would reverse when the conditions dictated? How would epigenetic effects last long term through clones ?
From the graph it would suggest just keeping them at 25 degrees C through both day and night? No swing in temps at all? But if you're gonna error, then error on the side of heat? Seems counter intuitive really, I worry if things start to get too warm.
From the graph it would suggest just keeping them at 25 degrees C through both day and night? No swing in temps at all? But if you're gonna error, then error on the side of heat? Seems counter intuitive really, I worry if things start to get too warm.
Well they claim to have used 'sexually undifferentiated plants' though that then raises some questions about the validity of their cannabinoid production study as presumably they mean vegging plants (i.e. does some metabolic change occur during flowering to increase cannabinoid synthesis or is it down to a greater density of trichome glands?).
GMT said:
Well this is the oddity in the study that I thought the table highlighted quite well. You'd expect more photosynthesis to equal more cannabinoid synthesis yet the data they gathered suggest that cannabinoid synthesis was higher in the plants grown in a 'cool' climate.
GMT said:
It depends on the definitions of epigenetics - the term itself means 'above genetics' so we're referring to genetic changes that don't require a change in the genome. So this typically means gene silencing which is done (very simplified!) by the addition of a methyl group to Cytosine (the 'C' base). So in the genome we find lots of sequences of CGCGCGCGCGCGCGCGCGCG which we refer to as CpG islands with the p referring to the phosphate seperating the bases (basically to separate it from meaning the C-G pairing). Once these become methylated they can act as a binding site for proteins which remove an acetyl group from histones to create heterochromatin.
So to step back...
This is what DNA looks like in the nucleus; what's called 'bead's on a string' (anal sex jokes ensue). The DNA chain is wrapped around a protein octomer (8 subunits) called a histone. These histones have multiple sites for modification (such as the aforementioned acetylation/deacetylation) which can alter their physical structure. Generally we see this to create 'euchromatin' which is very spaced out and easy for other proteins to access, as shown in the picture above. We also see heterochromatin in which the nucleosomes are very densely packed and thus restrict access to the DNA, leading to gene silencing.
You're right in that this can change given different conditions. However in humans and animals (which is what I've mostly studied, I have to admit), this typically only occurs during development and it's certainly quite odd to see 'de novo' (new) methylation or demethylation; it's a pretty major source of interest as a cause for cancer and other nasty things right now. In plants, we see discrete areas of developmental like cells at nodes and root tips etc. so I suppose the epigenetics are probably far less stable - I guess giving rise to different morphologies in different branches as you've seen yourself
Anyway seriously I do much prefer answering questions like this, it's kinda hard to think what would be interesting for people to read otherwise
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willyweed
could i cross a stinging nettle or other similar outdoor thriving plant in cold conditions,with a cannabis plant?
a,yes
b,no
c,why
a,yes
b,no
c,why
Thanks for explaining that the temperatures on the graph weren't the temperatures from the cultivation chambers, but now a new query, why weren't warm chamber plants placed under 15 C temps?
Thought I might jump in on this one, if that is actually a question.
a) Yes... using gm but not very practical for your current set up I should imagine?
b) No, because nettles are I believe distant relative of cannabis plants but they're far to different, you might aswell try to breed with a horse...
c) Obstacles include but are not limited to:
physical lay out
Genes in different locations
differening numbers of chromosomes
Cell surface receptors
Though Cannabis plants have be said to grow better around nettles. It is suggested nettles somehow interact with them as "companion" plants.
This may be due to the deterant effect of nettles on animals and their similar requirements from their environment.
Where nettles do well so does cannabis.
And lets not forget there are many thousands of wild populations of canabis all over the world
b - seperate species have a lot of difficulty breeding due to the differences in chromosome numbers etc. Basically it wouldn't produce viable seeds.
DemonPigeon said:
I guess you'd have to ask them
http://www.medicinalgenomics.com/wp-content/uploads/2011/12/Photosynthesis-and-Cannabinoid-Content.pdf
Here's a link to the full article for everyone anyway
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willyweed
what about gene splicing ? also it was a question with a little joke relating to another post i made in response to an answer bulldoguk gave to another thicko question i had to ask because i am slightly retarded and sometimes xim my words up ;_(
Sorry Willy, my bad man, don't think we saw the joke! xD
But as to the question I mean, yes you could technically do it in theory but it would be a lot of work. So temperature is the amount of energy available for atoms in the area - a higher temperature means more energy means the atoms move more. This is why we get evaporation occurring faster at higher temperatures etc.
If you want to try and modify a plant to be adapated to a temperature, you're looking at going through each metabolic process and trying to tweak it to work better at a slower speed. With current technology basically all we can do is copy and paste one gene from a cell to a different cell so you'd be looking at growing from cell cultures once you actually had GM weed, never mind how you'd be able to work out which cells had been successfully modified and which hadn't
Basically, it's a cool idea and it's the premise of why GM is exciting but it's so frickin' complicated that even people with access to multi-million dollar labs struggle doing it with much reliability or accuracy just because it basically goes against the point of forming cells in the first place (to isolate a set of genes).
