Lighting The use of 525nm (Green) LED's in light units

[MikeyB420]

Hi All,

I originally posted this comment in seymours Auto Mazar round 2 thread as to a possible cause to his 'spotting' on one his plants.

The 525nm wavelength LED can be used as a tool for eliciting specific plant responses such as stomatal control, phototropism, photomorphogenic
growth and environmental signaling. When combined with blue, red and far-red wavelengths, 525nm completes a comprehensive spectral
treatment for understanding plant physiological activity.

Well, ever since then I've been doing a lot of research into this subject. I will say at this point I do work in one of the better Physics labs in the
UK and many years ago I was employed in commercial horticultural plant breeding after college (not MJ though) and I still have friends in that
area who now use LED units.

The general consensus of all those that I have spoken to so far is that:

1. 525nm LED's are not suited for 99% of plants and that includes MJ.

2. The statement is not correct when it states 'can be used as a tool for eliciting specific plant responses such as stomatal control, phototropism,
photomorphogenic growth and environmental signaling. When combined with blue, red and far-red wavelengths, 525nm completes a
comprehensive spectral treatment for understanding plant physiological activity.

Specifically;

a. Stomatal control is related to uptake of CO2 and transpiration and is not affected by light.

b. Phototropism (I won't get too technical here, I don't understand some of it myself!) is only receptive to Blue, Red and Far Red areas of the
spectrum.

c. Photomorphogenic growth is the stage around germination and once again receptive to Blue, Red and Far Red only.

d. Environmental signaling: Bullsh*te was the answer from one friend, he said quote, " If I breathe on a plant it's being environmentally
signaled". Once again, nobody can attribute any benefit from 525nm LED's.

3. Several friends have said there would be possibly more benefit from 590nm (Orange LED's) being included, as this is closer to the Red
spectrum and is being trialed with certain crops at the moment but, not at the expense of Red!


Just my "My 2 cents"

Peace and Love

MikeyB.

 

[namvet25]

As far as I no there are no pure green led's and there must be a reason there isn't.

 

[MikeyB420]

As far as I no there are no pure green led's and there must be a reason there isn't.

Hi namvet,

There are pure green leds which operate at 555nm. Although I am led to believe that they are very inefficient at the present time. I'm still not convinced these are the way to go! The total green spectrum runs from 500 - 570nm and that includes yellow at the higher end.

PAL

MikeyB.

 

[Muddy]

Given how much research has gone into LED grow lights that past 5-6 years and the fact that none of the major manufacturers are using them, seems to support your findings.

 

[MikeyB420]

Given how much research has gone into LED grow lights that past 5-6 years and the fact that none of the major manufacturers are using them, seems to support your findings.

Always good to hear your views sir!

Well, Hydrogrow and another firm in Texas who supply agricultural led lighting are using them. Unless they know something my friends don't?

PAL

MikeyB.

 

[Anthropolis]

Well just along the lines of following logic, leaves and chlorophyll containing things look green because when white light hits it, it absorbs and/or refracts the colors within white except for green which it reflects right back and to our eyes as the color green. Plants don't do this or anything for no reason lol, if it's reflecting just green wavelength light, then it must not need it. My thoughts anyway

 

[mauricem00]

Hi All,

I originally posted this comment in seymours Auto Mazar round 2 thread as to a possible cause to his 'spotting' on one his plants.

The 525nm wavelength LED can be used as a tool for eliciting specific plant responses such as stomatal control, phototropism, photomorphogenic
growth and environmental signaling. When combined with blue, red and far-red wavelengths, 525nm completes a comprehensive spectral
treatment for understanding plant physiological activity.

Well, ever since then I've been doing a lot of research into this subject. I will say at this point I do work in one of the better Physics labs in the
UK and many years ago I was employed in commercial horticultural plant breeding after college (not MJ though) and I still have friends in that
area who now use LED units.

The general consensus of all those that I have spoken to so far is that:

1. 525nm LED's are not suited for 99% of plants and that includes MJ.

2. The statement is not correct when it states 'can be used as a tool for eliciting specific plant responses such as stomatal control, phototropism,
photomorphogenic growth and environmental signaling. When combined with blue, red and far-red wavelengths, 525nm completes a
comprehensive spectral treatment for understanding plant physiological activity.

Specifically;

a. Stomatal control is related to uptake of CO2 and transpiration and is not affected by light.

b. Phototropism (I won't get too technical here, I don't understand some of it myself!) is only receptive to Blue, Red and Far Red areas of the
spectrum.

c. Photomorphogenic growth is the stage around germination and once again receptive to Blue, Red and Far Red only.

d. Environmental signaling: Bullsh*te was the answer from one friend, he said quote, " If I breathe on a plant it's being environmentally
signaled". Once again, nobody can attribute any benefit from 525nm LED's.

3. Several friends have said there would be possibly more benefit from 590nm (Orange LED's) being included, as this is closer to the Red
spectrum and is being trialed with certain crops at the moment but, not at the expense of Red!


Just my "My 2 cents"

Peace and Love

MikeyB.

this is one of many peer reviewed studies that would seem to challenge your position http://www.plantphysiol.org/content/46/1/1.full.pdf also one grow light maker is trying to duplicate (fionia lighting fl300)their light has 40% in the 500-600nm range.this could be approximated using 1 430-440nm led and 2 6500k white with 2 3000k white.I just found this and will need to look into it further to find if it corrects the cal/mag deficiency caused by current grow lights after reading many peer reviewed studies on plant pigments and light use I feel that current grow lights place too much emphasis on red light and ignore the plants need for broad spectrum blue light but this mid spectrum light (500-600) may be critical as well.the current designs may be influences by the limited spectrum available when the NASA test were conducted some DIYers are getting good results using just white leds but these lack the 430-440 nm spectrum needed to stimulate some plant pigments including chlorophyll A. I hope this post does not offend anyone but this is stil a very new and evolving technology and there is still much disagreement regarding the best SPD for these lights.my hope is that this will stimulate intelligent discussion

 

[MikeyB420]

this is one of many peer reviewed studies that would seem to challenge your position http://www.plantphysiol.org/content/46/1/1.full.pdf also one grow light maker is trying to duplicate (fionia lighting fl300)their light has 40% in the 500-600nm range.this could be approximated using 1 430-440nm led and 2 6500k white with 2 3000k white.I just found this and will need to look into it further to find if it corrects the cal/mag deficiency caused by current grow lights after reading many peer reviewed studies on plant pigments and light use I feel that current grow lights place too much emphasis on red light and ignore the plants need for broad spectrum blue light but this mid spectrum light (500-600) may be critical as well.the current designs may be influences by the limited spectrum available when the NASA test were conducted some DIYers are getting good results using just white leds but these lack the 430-440 nm spectrum needed to stimulate some plant pigments including chlorophyll A. I hope this post does not offend anyone but this is stil a very new and evolving technology and there is still much disagreement regarding the best SPD for these lights.my hope is that this will stimulate intelligent discussion

It certainly should not offend anyone trying to get the best results! I was quite gobsmacked when I downloaded the first of your pdf's, I and a few others actually used that paper in the early 70's when the company I worked for were developing an improved variety of field bean for animal feed! Small World!!


Anyway, back to the plot. I think it is fair to say that, unless Universities, Plant Breeders etc. turn their attention and research towards the wonderful herb specifically, we are in a bit of a hit and miss situation at the present time. Of course, some of the more unscrupulous drug/chemical companies maybe working on this now but, given the legal status of MJ at the moment in most countries they are not going to be shouting out their results publically!

PAL

MikeyB.