Pet ,I don't know if I've made myself clear enough ....
What I'mn noticing (not for the first time to be honest ) here is this :
-
Most probably ,there is a
wl range ,somewhere in the
blue part
( hard guess ? Somewhere in between 450-480 nm ...) ,
that ' youngsters ' (
seedlings only ) ,utilise somehow ,to " figure out "
light intensity** ....
( through PHY or / and CRY action ,most possibly ..)...
** A kind of
geographical region prediction ?
Blue light at Mediterranean Spring is plenty ..
Only to be followed by a powerful ,long lasting summer sun ....
Something that does not happen in the Tropics -Equatorial zone ,in the same ways ...
As light there ,is totally different ..And plants ,grow differently under it ..
^^^ Check where at blue region ,the largest changes ,happen / peak ,
in relation with Sun's angle to the Sky .
( Seasonal Changes of Sunlight : Power -Spectrum-Angle-Duration )
Maybe ,plants ,(-have to _ ) know "what to expect " for the rest of their life cycle ,already from seedling stage ..
And ,my guess ,is yes ,that is the correct -crucial- timming ,for them ,to "realise " ,
in what kind of environment ( light-water-temperatures-humidity) are going to fulfill the rest of their life cycle ....
They have to "know " from soon enough ,so to start 'choosing' ,different gene expressions ,
in order to best 'acclimatize ' to the forthcoming seasonal (enviromental ) 'expected' changes .....
Survival of the fittest ..
The one "fitting" better / best to the environment ...
So,to continue ....
Most probably again,the photomorphogenesis occuring is the result of that " first" light "signals " ...
Making a plant "follow" somesort of a 'certain' pheno-expression .....
( bushy -stocky-branchy-leafy-dark green leaves-thick stems -plenty of ' bud sites '-massive lateral rootballs- etc )
What ,I 've noticed is this :
The "stimulus" is needed only for a shortwhile ....
As plant gets 'older' -& bigger - that kind of light ,may start affecting -in a negative way -the metabolism of a "grown/"adult" plant ...
WTF ...I'll say it ...
.Blue light is for plants what is milk ,for mammals ....
Beneficial for an infant-baby , but builds lots of fat around internal organs if still consumed on later stages of growth ....
Along with messing up the stomach and the rest after ...
Mammals can consume ,trouble-free & beneficially for health , "by-products" of 'fermented' milk,like cheese or other ..
But not ,raw milk ...
Ok...Something like that ...More or less ...
Say the stimulus is there ,for the first week of vegging or so ....
Afterwards ,even if the stimulus is 'removed' (no more blue light ) plants ,keep on following same "growth pattern " ...
Gene -expression is 'locked ',somehow ..
For certain aspects of the plant ...
And won't change no more ...
Not in an easy way,at least ..It will stress the plant(s),most probably
(I.e . HPS=> Sunlight ...Or Sunlight => HPS ....Many plants ,die or suffer ...)
Plant has chosen ,how to ' express ' certain ,
permanent ,characteristics /procedures ..
'Stimulus' is no longer needed ....
Or worse ,it can have deleterious metabolic effects on adult plant(s),if persistent ...
( I.e Photo-inhibition , low mesophyll conductance of CO2 ,heat stress ,excess transpiration ,etc )
Specially, regarding a
non-fluctuating light power/duration of an artif . lighting schedule ...
That's what I've been noticing ...
That ,indeed ,some more blue light ,is needed at the very start ..First 10-14 days ...
Then ,the plants* ,can go on living & thriving ,even with detrimental amounts of blue light ..
(As the plants at current grow do .... )
-*Always referrin' to mj ... Not to be misunderstood-