Far red, red, uv, EOD treatment

[Nuggie]

I've been reading lots on this subject and there are some things that I've come across that make me go hmmmm.

LED grows need more magnesium and calcium, according to Dutch passion they believe that something is missing in the led spectrum that causes this. I've also read that low temperatures cause mg and cal deficiencies. If leds are missing far red wavelength light, but far red serves to heat up the leaf surface and accelerates growth (Emerson effect), this should then serve to alleviate the mg and cal deficiencies. This leads to a problem though by adding more infrared you promote stretch and shade avoidance plant responses which in an led grow decreases the efficiency of leds because the lower leaves are farther from led and leds drop off in intensity quite fast with height. This forces us to sog or scorn to maximize plant growth.

This leads me to one conclusion, when adding far red the logical thing to do is to balance the far red addition with uv since blue light shortens the internode distance. This would be a whole day treatment with some variation at beginning and end of day - like a balancing act of the whole spectrum. I have seen nothing about the ratio of uv to far red, would need to be in some proportion to each other like in nature. Seems like most of literature out there focuses on red to far red ratio with very little regard for uv, red and far red ratios all together - i feel this is somewhat typically human, monitor two things as its easier to monitor and setup and run an experiment but add a third variable and now it becomes exponentially more difficult to evaluate and perform experiment. The uv and far red would be on all day but uv would peak at midday and far red peak at the start and end of day. The symphony of lighting would be that the sum of the uv and far red would be such that the plant grows as if it were normal, no abnormal stretch, no short/stunted plant just a normal representation of the plant that is as supposed to be. Stretch at beginning and end of day but uv during day to keep the infrared in check.

[TheOther]

There are few more recent studies that I've been wading through. Blue/Red /Far Red/ Par ratios are more dependent than we thought.
This is flow chart starting to make sense, unfortunately. The Botrytis study was eye opening, read that
Electron Transport flow chart

Big reading list:
https://bmcplantbiol.biomedcentral.com/ ... 018-1310-9
https://www.researchgate.net/publicatio ... luorometry
http://www.plantphysiol.org/content/158/4/2042.full
https://www.sciencedirect.com/science/a ... 1918621306
http://www.plantphysiol.org/content/176/2/1311
https://www.sciencedirect.com/science/a ... 5216301654
https://www.frontiersin.org/articles/10 ... 00322/full

[TheOther]

Maybe that is Ion flow chart above, my brain is too overloaded with both right now.
Alcohol modulation should fix that.

[TheOther]

Plants Actively Avoid State Transitions upon Changes in Light Intensity: Role of Light-Harvesting Complex II Protein Dephosphorylation in High Light
This study looks at plant proteins affected by light, and how to regulate PS1 and PS2 states.
http://www.plantphysiol.org/content/168/2/721.full

[Nuggie]

Maybe that is Ion flow chart above, my brain is too overloaded with both right now.
Alcohol modulation should fix that.

Yeah, it takes me a while to digest these articles. I like the second posting you listed, it seems to make sense and includes blue light, also never heard of second emerson effect until this.

[TheOther]

I got some 20watt Emerson boards attached to a Bridgelux EB2 3500k @120w per 2x2. Haven't tried them yet. 3:1 ratio 660nm :730nm EpiLeds probably.

Can't control the R:FR channels separately, So I'm going to run some 20w RGB strip light for blue:red channels during the day, modulate as needed during grow.
Turning them off 1/2hr before lights out and running Emerson board for 45 minutes should be early enough to control PS2 state using 730nm far red without overwhelming the plant with 660nm red. Unsure if adding timing gap before EOD is beneficial, have to read the modulation study some more.

[TEKNIK]

If you have 660nm it won't work for EOD properly, rbg strip really isn't very bright at all, hardly worth running it.

[TheOther]

If you have 660nm it won't work for EOD properly, rbg strip really isn't very bright at all, hardly worth running it.

Its an Emerson Board with 660 and 730 for EOD.
The RGB strip doesn't have to be bright, it just has to trigger PSI and PSII states, like the Emerson board.
The hard part is determining how many watts need to be applied vs PAR output. Every White LED is going to have a different footprint, different ratios vs PAR for controlling PS1 and PSII.

Timing of channels( Blue/R/FR/PAR) and rough working ratios needed to control growth are whats lacking at this point.
They are looking at green for another control as well, due to the canopy penetration green light achieves.

I used the RGB strips once before, seemed to do well with flowering and finishing. No science, just bro logic.
I didn't mount them overhead. Definitely not bright enough.
Mounted on pvc tubes hanging vertically in the canopy, so they light it from the inside vs overhead vertically.
Started with red only , then added blue , then RGB to finish. Best larf buds ever, the ones that missed pruning...bro.

[Nuggie]

I am going with a 50 W incandescent heat bulb turned on periodically thru day as well as start and eod treatment, its on a WiFi programmed plug, the plants are responding really well but as expected stretching a little more. Leaves are larger than normal and turning a deeper shade of green - will have to monitor this to see if consistently does this. This is my hack job at it, bulb provides a lot of representation for wavelengths between 600 and 800+ nm. It overdoses it on red at 3000k but at 4000k this would be perfect. I am going to commit to adding separate leds in 365, 385, 405, 415, and 730. The uv and far red will be run off independent inventronics programmable drivers to separate the lighting schedule. Figure 7-10 watts total blue, 7 watts total far red per 100 watts.

[Nuggie]

There are few more recent studies that I've been wading through. Blue/Red /Far Red/ Par ratios are more dependent than we thought.

https://www.frontiersin.org/articles/10 ... 00322/full

The last article is money!