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Nighttime starch degradation, the circadian clock, and plant growth

Dkgrower

Active member
Veteran
if i remember right, the higher the brix level, the higher the ammount of all non liquid compounds is in the sample (sugars, chlorophyll, anthocyanins, ...), hence i guess the lowest measurement would provide the smoothest smoke, since we are trying to accomplish the opposite of what a refractometer is used (in vegetables and fruits, the higher the brix level -> more sugars, ... -> better flavor).

blessss
ps.: in tobbacco, they use glycerin to prolong the burning (keeps the tobbacco moist), the sugar, is added for better flavour and masking some of the harshness of the smoke


Cool - thanks for clearing that up, it makes sense to go with low brix readings , so in the morning is optimal or would it be best just to keep em in the dark and harvest after 14 houres keeping them in the dark ?

Then the plants would have minimal starch and non to very littel sugar.

Good day to ya all
 

jayjayfrank

Member
Veteran
it seems to me the window of harvest becomes NightTime+10Hrs

so if you are running 12/12, you wait for the light to go off and harvest in 22 hours(night + 10)


also could this be related to the reason why tropical sativas should be run in a 10/14 light-dark cycle? because of how they use starch reserves at night?
 

purple_man

Well-known member
Veteran
nope tropical sativas most of the time recieve 12/12 during whole of their life, hence shortening the period facilitates the ripening process...

not sure dkgrower... me thinks youll have to make a comparison, one part harvested before lights up, and the 2nd half with additional 14 hours of darkness (if i understand right), note the brix readings, and after a nice cure, the smoke should be a good indicator which one worked better :)

blessss
 

bigshrimp

Well-known member
Veteran
Harvest during the end of night or just after lights turn on, that is when starch levels will be lowest. If you want to ensure all reserves are used you would give them an extra couple hours of darkness. Assuming cannabis behaves the same as aradopsis.
 

Dkgrower

Active member
Veteran
nope tropical sativas most of the time recieve 12/12 during whole of their life, hence shortening the period facilitates the ripening process...

not sure dkgrower... me thinks youll have to make a comparison, one part harvested before lights up, and the 2nd half with additional 14 hours of darkness (if i understand right), note the brix readings, and after a nice cure, the smoke should be a good indicator which one worked better :)

blessss

I tryed with killer queen i harvest a good amount after i extended the dark periode by 2 houres - cutting them down in the dark

For the other end off the spectrum i harvest again a desent amount just before ligth out -

Ditte read the brix to much going on but they just got deleaved and are haning to dry

I am really trying to nail the perfect harvest window and giving the last respect befor the chop chop and find this topic very important

Bom shiva
 

purple_man

Well-known member
Veteran
way to go bro! please let us know, what differences if any you experience, once the ladies are dried...

blessss
 

bigshrimp

Well-known member
Veteran
If starch levels are lowest as lights turn on, why is it recommended that we take cuts in the morning?
 

jayjayfrank

Member
Veteran
who recommends that?

and i bet if i splice some 'starch genes' into an indica it wouldnt flower till 10/14

there has to be some other reason than "its because indica is indica and sativa is sativa and thats that"
 

purple_man

Well-known member
Veteran
yeah who recommends that??? first time i hear this in nearly 2 decades...

nah jayjay... the thing is, if i were to infuse you with ringer liquid supplemented with sugars and vitamins (aka "multivitamin" ringer fluid), while you are asleep, you would not wake up, in a similar way a plant would response, if you were able to disrupt/modify it's starch metabolism....

blessss
 

floral

Member
Auxins are regulated on a circadian rhythm, too. I have read various reasons for taking clones in the morning, some involving moisture levels and heat and others saying that auxins are higher in the morning.

Separate issue from harvesting after nighttime stash of starches have degraded.
 

trichrider

Kiss My Ring
Veteran
"Providing sugar in the growth medium prevents carbon starvation during the night and
restores normal plant growth."

molassess...

uh, when you dry/cure isn't the plant using up those starch/sugar reserves?
it makes sense to start with the smallest amount though.

...and you're removing the fans which store those sugars/starches prior to drying, right?

when you burn sugar it is disgustingly ugly, you wouldn't want that in your flowers.

monitor senescence to alleviate chlorophyll exposure by removing fan leaves as they yellow. translocation thus relies on storage in smaller sugar leaves which depletes them of their sugar load.

it may well reduce yeild, but as a personal grower, i could shive a git.
 

floral

Member
I tryed with killer queen i harvest a good amount after i extended the dark periode by 2 houres - cutting them down in the dark

For the other end off the spectrum i harvest again a desent amount just before ligth out -

Dkgrower, how did your test turn out? Any differences?
 

Max Headroom

Well-known member
Veteran
An important hallmark of the circadian clock is its free-running 24-h rhythm. Free running refers to the fact that, once entrained by light signals, the circadian clock maintains a 24- h rhythm in continuous light or continuous darkness, anticipating dusk and dawn according to previously encountered conditions.

interesting!
i guess that's why i had troubles last time, when i had day-time in veg from 9AM to 3AM but in flower switched to 7PM to 7AM?
 

GET MO

Registered Med User
Veteran
interesting read... I always did my outdoor when it smelled best, some strains smelt better in morning, others in afternoon.
 

GET MO

Registered Med User
Veteran
wouldnt those starches and sugars add to your yield? or do they not weight that much?
 

earthwyrms

Active member
An important hallmark of the circadian clock is its free-running 24-h rhythm. Free running refers to the fact that, once entrained by light signals, the circadian clock maintains a 24- h rhythm in continuous light or continuous darkness, anticipating dusk and dawn according to previously encountered conditions. In fact, the property of being a 24-h timer has revealed the involvement of the circadian clock in the control of starch degradation. When plants are grown in light–dark cycles shorter or longer than 24 h, abnormal starch degradation patterns are observed during the night. In 28-h light–dark cycles (14 h of light, 14 h of darkness), starch is degraded extremely fast, so reserves are exhausted before dawn—specifically, at 10 h into the night rather than at the actual dawn after 14 h of night (Fig. 1b).


so if the plant is kept on a non 24 hr light cycle it won't lock in and can start to get used to/mutate to another one?

so if it is on a 23/13 cycle, then foliar sprays at night towards the end of the dark period could offset the starvation/boost growth?
(someone here said sativas need at least 13dark to go to flower immediately and 23 light gives it 36 which is a half day cycle off )

what if it gets used to a pattern of cycles rather than a fixed one 13/13, 14/13, 15/13, 16/13, 17/13, 18/13, 19/13, 20/13, 21/13, 22/13, 23/13, 22/13, 21/13, 20/13, 19/13, 18/13, 17/13, 16/13, 15/13, 14/13.......

13/13, 14/13, 14/14, 15/14, 15/15, 16/15, 17/14, 18/14, 19/14, 19/15, 19/14, 18/14, 17/14, 16/15, 15/15, 15/14, 14/14, 14/13.....


or 11/13, 12/13, 13/13, 14/13, 15/13, 16/13, 17/13, 18/13, 19/13, 20/13, 21/13, 22/13, 23/13, 22/13, 21/13, 20/13, 19/13, 18/13, 17/13, 16/13, 15/13, 14/13, 13/13, 12/13.......
which i think gives it 720hr cycles

12/13, 13/13, 14/13, 15/13, 16/13, 17/13, 18/13, 19/13, 20/13, 21/13, 22/13, 23/13, 22/13, 21/13, 20/13, 19/13, 18/13, 17/13, 16/13, 15/13, 14/13, 13/13...
i think gives 671, one hour short of 672 which is 28*24, approximately a full moon cycle in days times the hours in a day

just wondering
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
Making a plant to "get used to" a non-24 h based day will be anything but simple because some of the "molecular switches" (notably, we don't even know all involved mechanisms of the circadian clock) involve degradation and half-lives on a chemical level. This means, the plant would have to express either completely new chemicals or at least different amino acid or RNA sequences. Seems like the circadian clock is a very-very old machinery possibly as old as life on earth. Changing one might require to change the other...
Certainly, there are effects such as sugar translocation and starvation signals which might be adjustable especially with human interventions but these do not suffice to really change the internal clock.
But I like the idea of tweaking those things with the hope of altering the plants physiology in a way beneficial for our intentions.
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
wouldnt those starches and sugars add to your yield? or do they not weight that much?
They do ;) .
But as mentioned already above by someone else; high sugar/starch levels in the final product are not desirable. Tobacco farmers know this for centuries. On the other hand, flowers and "sucker" leaves are sink tissues and hence way less affected by night-time starch degradation than are fan leaves (and it's the latter one uses for tobacco production).
As a side note, one effect (if not the most important one IMHO) of proper flushing is a starvation response pushing the plant to invest more energy (= carbohydrates) into their root zone and diminishing aboveground starch accumulation.
 
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