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  • earthwyrms
    replied
    here's a repost with color highlights to help visibility. i imagine the form above is better for a poster to edit, while this one is easier on the eyes.


    * 12/12....... far red (730nm) on during first (0) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 12/12....... far red (730nm) on during first (30) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 12/12....... far red (730nm) on during first (ALL) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (0) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (30) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (ALL) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    Leave a comment:


  • earthwyrms
    replied
    i am still somewhat confused. please copy/paste this with the findings. it will make it a whole lot easier to understand, remove the guesswork and show what we know, what we don't know and what we predict.

    * 12/12....... far red (730nm) on during first (0) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 12/12....... far red (730nm) on during first (30) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 12/12....... far red (730nm) on during first (ALL) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (0) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (30) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower

    * 10/14....... far red (730nm) on during first (ALL) minutes of night.
    (leave one, [observed] or [predicted]) __ weeks to flower
    Last edited by earthwyrms; 11-17-2015, 04:53.

    Leave a comment:


  • Bubbleblower
    replied
    Originally posted by Phaeton View Post
    Now the shorter nights are being tested. The plant is going into it's second week of 14/10.
    It will be another five harvests before anything definitive can be said but so far so good.
    This is after 19 days 14/10:



    It works if you use far red, but the downside is it will take a few weeks longer to finish.
    The same goes by the way for longer than 24h light cycles, while shorter schedules have the opposite effect.

    Some sativa's will even start to flower with less than 8 hours dark if it gets darker relatively fast = 3.5 minutes per day.
    They are much more sensitive to this change than indica's, at our latitude after solstice they are auto flowers avant la lettre.

    Leave a comment:


  • earthwyrms
    replied
    Originally posted by Phaeton View Post
    I did five harvests with a half hour of far red immediately after lights out. These were done at 12/12 to establish a baseline.
    The strain is a sativa that normally produces seeds starting at six weeks, it smokes so well that early harvests worked out and the plant is productive.
    While establishing the baseline it was noted that the sativa no longer produced seeds at the six week mark. In fact taking the plant all the way to thirteen weeks did not produce any seeds.
    Five harvests were done to confirm what happened was not an anomaly.

    Now the shorter nights are being tested. The plant is going into it's second week of 14/10.
    It will be another five harvests before anything definitive can be said but so far so good.

    to clarify, the sativa normally seeds in 6weeks 12/12? and far red, 730nm for 30min of dark period prevented this?

    i originally was puzzled and thought maybe you meant the baseline was 12/12 no far red and no seeds formed, then 12/12 with far red got 6week seeds.

    it's hard to tell because "normaly" could mean; the sativa was not grown previously and the 1st 5 were "normaly" after 5 times using far red and some later baseline test at 12/12.

    it is confusing to me because if i interpret it in the case that normal means, without far red, then it implies far red prevents seeding. with it being tested again with even less light, i could assume you meant it did work; unless, it was to prove far red is equally or more preventative to seeding than less light at 14/10.

    i also am uncertain if you mean to say that seeding and flowering are affected differently in male and female plants, by far red light.

    please write the details
    Last edited by earthwyrms; 11-12-2015, 22:22.

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  • Phaeton
    replied
    I did five harvests with a half hour of far red immediately after lights out. These were done at 12/12 to establish a baseline.
    The strain is a sativa that normally produces seeds starting at six weeks, it smokes so well that early harvests worked out and the plant is productive.
    While establishing the baseline it was noted that the sativa no longer produced seeds at the six week mark. In fact taking the plant all the way to thirteen weeks did not produce any seeds.
    Five harvests were done to confirm what happened was not an anomaly.

    Now the shorter nights are being tested. The plant is going into it's second week of 14/10.
    It will be another five harvests before anything definitive can be said but so far so good.

    Leave a comment:


  • Bubbleblower
    replied
    Originally posted by Only Ornamental View Post
    That whole far red light thing is simply fascinating.
    Probably another reason why some sativa's start flowering here (the kop van Noord Holland ) with less than 8 hours of night.

    "During the night, the PFR converts back to PR.
    The PR form is needed for the release of the flowering signal.
    You need X hours of darkness in which to convert all the PFR present at sundown into PR and carry out the supplementary reactions leading to the release of the flowering signal ("florigen").

    If this process is interrupted by a flash of 660-nm light, the PR is immediately reconverted to PFR and the night's work is undone (C)
    A subsequent exposure to far-red (730 nm) light converts the pigment back to PR and the steps leading to the release of "florigen" can be completed (D)
    Exposure to intense far-red light at the beginning of the night sets the clock ahead about 2 hours or so by eliminating the need for the spontaneous conversion of PFR to PR (E)."



    That's why HPS does so much better as you would expect based on theory, it releases a large amount of FR after it is switched off.
    If you have led just add an incandescant which you switch on 20 minutes before lights go out and leave on for half an hour.
    It will make a huge difference.

    Leave a comment:


  • Only Ornamental
    replied
    It should (at least in a scientific setup) even suffice to use it for a few minutes directly after lights out to turn all the Prf into Pr. Thereby, the perceived night is as long as the 'apparent/real' night whereas under normal conditions, the perceived one is shorter by 1-4 hours depending on the plant species.

    Leave a comment:


  • earthwyrms
    replied
    ah, so possibly the 175-180nm would not affect this though and stimulate THC. daytime would seemingly be optimal though.

    i don't understand though, if red converts Pr to Pfr and Pfr turns to Pr overnight, would an far red diode only turned on for the duration of the night, help (if far red helps Pfr turn to Pr)?

    Leave a comment:


  • R043
    replied
    Lets see if I can clarify things for you. Since I am not aware of what you already know, forgive me if I go in too much details on things you already have a good grasp on. At least it might be of interest for people who read this and haven't been exposed yet to those concept.

    First remember all of this is theoretical and the link I provided and that you quoted is the only one I found on the net where someone claim to have success using it on Cannabis.


    "Long day and short day plants react just the opposite to phytochrome manipulation"


    Cannabis is a short day plant. As you know, if you keep the daylight long enough, it will stay in vegetative. If you want your plant to start flowering, you will reduce the daylight length. Wich is why it is called a short day plant.

    Long day plants are exactly the opposite. They will stay in vegetative as long as the day are under a certain daylight lenght. To induce flowering, you will need to expose them to longer daylight.

    You would think that plant woud somehow know the duration of daylight lenght, but actually it is the duration of the night that the plant is aware of (in a manner of speaking). So calling them long day or short day is kind of a misnommer and calling them short night or long night plants would make more sens.

    Back to the quotation, we have clarify short day and long day plants. Now "phytochrome manipulation" in this context refer to using the knowledge about Pr and Pfr to have an effect on inducing or preventing flowering.

    Outside the scope of this article, phytochrome manipulation could mean something else. For exemple, elongation is known to be tied to the Pr/Pfr ratio whithin the plant during day time.

    Before going on with the next part of the quote let's specify something.

    The minimal night lenght necessary to induce flowering in short day plant is called the critical period. In long day plant, the critical period is the maximum night length that induce flowering. It should be noted that different strains and most likely different pheno will have different critical period. 12/12 have been adopted and widely used because it is short enough to induce flowering in most strain. Yet, there are report of strains (mostly some Sativas and Sativa dominant hybrid) responding better with longer night than 12 hours.

    Earlier in this thread I mentionned the theory that at the beggining of night time, flashing Cannabis with Far Red could theoretically reduce the night critical period. The article we are quoting state a slightly different approach.

    Basically, he says there are strains that will flower under 14/10 (so the critical would theoretically be 10 hours). Yet he also says that from his experience, a strain flowered under 14/10 will take longer to finish it's flowering cycle than ir it was under 12/12. Instead of flashing his Far Red at the beggining of the night, he adds it to his spectrum at the end of the day cycle, making sure also to lower his Red spectrum.


    "Where as high red, low far red light stimulates flowering in long day plants, it's just the opposite in short day plants like cannabis"


    Originally posted by earthwyrms View Post
    does the writer mean High Far Red and Low Red is beneficiary for flowering cannabis?
    No, he is just saying that you need at the end of the day cycle a high Far Red and low Red spectrum to help induce flowering and to avoid slowing the full flowering cycle all the while using 14/10 (which he states increase total yield).

    Note that it does not mean that it would be benificial to keep this spectrum day long through flowering. Or that it would be beneficial under 12/12 (yet it could be with some strains that respond better with 11/13).

    Originally posted by earthwyrms View Post
    i'm not sure what to make about the rest of his paragraph on that with wattage being unmentioned
    I am not sure what exactly you refer to. But you do not need wattage to make sens of all this. The spectrum is the intensity of light at different wavelenght. So supplementing Far Red shouldn't be too hard. But making sure to have a low Red would need some creativity for sure. If I was growing under HID and really wanted to try this, I would add some LED whitout the Red band and turn off the HID for the last hour.

    Originally posted by earthwyrms View Post
    Pr absorbs red, Pfr absorbs far red.
    This is 100% correct.

    Originally posted by earthwyrms View Post
    they can interconvert somehow. red helps Pr turn to Pfr.
    Not somehow. When Pr absorb Red, it turns into Pfr. When Pfr absorb Far Red, it reverts to Pr.

    What is interesting is that even in the absence of Far Red (so at night) Pfr slowly revert to Pr. This would be one of the different mechanism by which plants are aware of the night lenght. The longer the night, the less Pfr left.

    Originally posted by earthwyrms View Post
    Pfr can be bound to a protien and work on DNA (im guessing it doesn't back convert after this or is used up?)
    I was exposed to this for the first while watching the video from your link. It was only state as an exemple of the different role Phytochromes plays. The video stated it was the case of certain plants only. I do not know if Cannabis is one of them but it is irrelevant to this discussion.

    I really did not understand exactly where you were getting at with the rest of your post. However you talked about very high nm which are purely infrared and not Far Red. Pfr will aborb less past 730 nm and I would think not much above 800 nm (yet I might be wrong).

    I have joined the graph of Phytochrome absorbtion spectrum so you can see visually want I am talking about. It is interesting to see they absorb also in the blue wavelenght and even in UV. For this reason, I would avoid pulsing UVB at night. Alhto I might be wrong and it might work, I see not benefit in trying this since UVB addition in day time works.

    Well I hope this was useful.
    Attached Files

    Leave a comment:


  • earthwyrms
    replied
    R043 i found it odd on http://www.growweedeasy.com/phytochr...ation-cannabis that the writer wrote

    "Long day and short day plants react just the opposite to phytochrome manipulation. Where as high red, low far red light stimulates flowering in long day plants, it's just the opposite in short day plants like cannabis."

    does the writer mean High Far Red and Low Red is beneficiary for flowering cannabis?

    i'm not sure what to make about the rest of his paragraph on that with wattage being unmentioned

    i watched this video, https://www.youtube.com/watch?v=xMCupB8pSZ8, which is 1:39 minutes, which gave me a start on understanding phytochromes, although i got confused at the end. Pr absorbs red, Pfr absorbs far red. they can interconvert somehow. red helps Pr turn to Pfr. Pfr can be bound to a protien and work on DNA (im guessing it doesn't back convert after this or is used up?)







    perhaps if the main lights are turned off or dimmed for an hour and the temperature is either kept constant from a heat lamp also use the far red LEDs and/or infrared LEDs, there could be a reset or hourglass effect.

    maybe not

    concerning the night time anyway, there's a black (totally black opaque glass) ceramic heat bulb by fuxin that is black and made tobarely light and glow like the moon i believe it was written.

    the bulbs are in wattages from 25W to 100W and the flat faced type with the spiral pattern is supposed them to be better for efficiency

    they are "E27 ceramic heat bulb" or something like that [beware of mains types, 110v or 220v] it gives off Far Infrared

    Black Dog LED has a paper about leaf temperature.
    https://www.blackdogled.com/lst

    "There is a prevailing consensus that 75 °F is the ideal ambient temperature to grow Cannabis under HPS lighting without CO2 supplementation. This experimental result indicates that an 84 °F ambient air temperature is required to achieve the same optimal leaf surface temperatures when using plant-optimized LED lighting-- and that a 75 °F ambient air temperature with LED lighting would not achieve optimal leaf surface temperatures, slowing metabolic rates and leaf and flower production."



    maybe some combination of the fuxin far infrared lamp, the 730nm far red LEDs and/or the 940nm invisible infrared LEDs can have a good effect on plants if turned on as the lights are turned off or before they come on for some amount of time.

    the 940nm LEDs are supposedly true invisible infrared which maybe doesn't do anything beneficial although i don't know if i saw any tests otherwise.
    i am wondering about the 1000nm to 1500+nm fiber optic/telecommunication wavelengths and what they might do too.

    i was wondering if UV flashes or pulses at night instead day of 280nm might do something good. maybe randomly or patterns or super low amounts continually. there are led diodes from 275nm +-5nm at mW levels, which maybe can be run continually, even at night to make a possible simulated background for the plant to produce THC to counter.
    I read 280-310nm stimulates THC production

    about the lower light intensity
    you both may be interested in post #344 here
    https://www.icmag.com/ic/showthread....108973&page=23

    and lastly, what if 650nm lasers only half a watt can be focused to cover plant leaves, not as a dot, but through a collimated image projector or just a unfocused lens. there are lots of 100 diodes encased in heatsinks at 5mW power (consumption or radiant, i don't know) for around $23 i think.

    thats got to be a good experiment, plant with light as control, same plant with same light and those lasers shining diffuse on the leaves as the experiment, in amounts untill a difference is noticed.
    i think 650nm is close to one of the peak absorbtions, not peak but close to 630nm and i t don't remember the other one in the 600s.

    Leave a comment:


  • R043
    replied
    Oh and I am not sure if it is a typo but for the people who will read this and get confused, it is actually the Pfr that revert to Pr in the absence of light. Not the other way around. That is the reason you want to flash Far Red light, so Pfr phytochrome revert faster than they do naturally.

    One last thing, if this was the only mechanism at work for the plant to know the night time lenght, one could flash Far Red for an hour only and then start another day cycle. Of course this won't work and we know that this model (called the hourglass model) is incomplete. Still, shortning the night lenght by one or more hours would be great.

    Leave a comment:


  • R043
    replied
    Yes it is a very interesting topic. There are obvious advantage if it works, that is for sure.

    You mentionned some and I others, there are probably more we haven't think of yet.

    A long day plant could be kept in veg while receving longer light time and faster grow.

    Lots of cool possibilities.

    I've said earlier in this thread that I haven't found anyone who claimed to have try this with success. While going through my archives, I've found a link I forgot. I have no idea what degree of credibility to give the guy but actually I was wrong. He does claim to have use this with success.

    http://www.growweedeasy.com/phytochr...ation-cannabis

    Originally posted by Only Ornamental View Post
    ...It also might tell me the natural delay or Pr to turn into Pfr or in other words the 'real' minimal night length and not the apparent one...
    I am not sure what you mean by the "apparent one". Maybe you meant you go with a standard 14 hours of darkness (which would be the apparent one) and mean you never tried to find the exact minimum critical (that would of course vary from strain to strain).

    In any case, I've heard the best way to find the exact critical period would be to start, when ready to flip, with 9 hours of darkness. Each week you add 15 minutes of darkness. Once you see flowers, you know the critical is somewhere close to your current night lengt minus 15 - 30 minutes (1 to 2 weeks prior to this point the plant started flowering). Next run you can pinpoint this precisely.

    As for psychoactive hemp you got me extremely interested and I am on my way to the link in your sig. Right now.

    Leave a comment:


  • Only Ornamental
    replied
    That whole far red light thing is simply fascinating. It also might tell me the natural delay or Pr to turn into Pfr or in other words the 'real' minimal night length and not the apparent one (e.g. something between 10 and 13 hours based on other plant species). Lets assume that the use of far red would turn the minimal night length for flower induction down to 10, then I could use my meagre wattage 14 instead of 10 hours per day and still keep the natural (allegedly best) day length interval. This is a considerable increase in photosynthesis and hence product quality combined with less stretch and blablabla .

    Some of my hemp varieties, yes fibre/seed hemp aka industrial hemp, contain psychoactive individuals. Check out my gallery and follow the link in my signature for more infos.

    Leave a comment:


  • R043
    replied
    How painful that I can't edit. I know hemp is Cannabis.

    And this : I wanted to make this is what you meant

    Should read : I wanted to make sure this is what you mean

    Leave a comment:


  • R043
    replied
    I completly understand. In any case I would still be curious in the outcome of your experiment so there is no reasons why you shouldn't be either.

    DLI was the acronyme you were looking for. Daily Light Integral.

    I didn't really assumed you would grow only one strain, it just came out like that. If you grow something with 14 hours of critical then there is definetly a good reason to try and reduce this. I am still wondering why you think it is a nice thing.

    Maybe by now you have figured I am quite curious, which is why I need to ask. When you refer to hemp, do you mean you are growing the non psychoactive hemp as opposed to cannabis ? Nothing wrong with that. Just a bit surprising. I am asking because I wanted to make this is what you meant and not some kind of exotic old school cannabis strain.

    Should it be that I misunderstood and that it was indeed some psychoactive variety you refer to as hemp, then I would be quite curious about in what ways do they react to temperature and DLI.

    Leave a comment:

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