Praying leaves

cobshopgrow

Well-Known Member
something ive found.
"Shade avoidance-related leaf positioning has been reported in Impatiens (Whitelam & Johnson 1982), tobacco (Hudson & Smith 1998; Pierik et al. 2004a) and Arabidopsis (Vandenbussche et al. 2003; Millenaar et al. 2005), with leaf inclination varying with the ratio of red light to far-red light. In Arabidopsis, mutants deficient in phytochrome are hyponastic (Ballaré & Scopel 1997; Vandenbussche et al. 2003). In addition to this regulation by light quality, leaf inclination is also dependent upon light intensity, with leaves in Arabidopsis becoming more horizontal with increasing light intensity (Hangarter 1997; Millenaar et al. 2005; Fig. 1). While this intensity-dependent response of rosette species is consistent with a role in shade avoidance, it differs from the response of many non-rosette species, in which leaves generally become more vertical with increasing light intensity as a protective mechanism against photodamage from excess light interception (King 1997; Valladares & Pugnaire 1999; Falster & Westoby 2003). "

our plants are shade avoiders too.
 

bam0813

Well-Known Member
something ive found.
"Shade avoidance-related leaf positioning has been reported in Impatiens (Whitelam & Johnson 1982), tobacco (Hudson & Smith 1998; Pierik et al. 2004a) and Arabidopsis (Vandenbussche et al. 2003; Millenaar et al. 2005), with leaf inclination varying with the ratio of red light to far-red light. In Arabidopsis, mutants deficient in phytochrome are hyponastic (Ballaré & Scopel 1997; Vandenbussche et al. 2003). In addition to this regulation by light quality, leaf inclination is also dependent upon light intensity, with leaves in Arabidopsis becoming more horizontal with increasing light intensity (Hangarter 1997; Millenaar et al. 2005; Fig. 1). While this intensity-dependent response of rosette species is consistent with a role in shade avoidance, it differs from the response of many non-rosette species, in which leaves generally become more vertical with increasing light intensity as a protective mechanism against photodamage from excess light interception (King 1997; Valladares & Pugnaire 1999; Falster & Westoby 2003). "

our plants are shade avoiders too.
Interesting correct me if I’m wrong but doesn’t the last paragraph starting at fig. 1 claim it would be to shade and not to avoid shade or is MJ a rosette species?
 

Hairybuds

Well-Known Member
Interesting correct me if I’m wrong but doesn’t the last paragraph starting at fig. 1 claim it would be to shade and not to avoid shade or is MJ a rosette species?
Yeah I’m confused too as to the conclusion of those statements. Until it says cannabis and light response I think it’s futile to draw conclusions
 

cobshopgrow

Well-Known Member
Interesting correct me if I’m wrong but doesn’t the last paragraph starting at fig. 1 claim it would be to shade and not to avoid shade or is MJ a rosette species?
i understood it so far.
there are only 2 types of plants, shade avoiding and shade loving plants.
cannabis is classified as shade avoider.
the article is only refering to shade avoiding plants.

i would think the relevant part for us should be.
"response of many non-rosette species, in which leaves generally become more vertical with increasing light intensity as a protective mechanism against photodamage from excess light interception "
as cannabis is a non rosette species but still a shade avoider.
 

bam0813

Well-Known Member
Agree that’s the relevant part. But I read that as the plant, non rosette species mj, does it for shade.

become more vertical with increasing light intensity as a protective mechanism against photodamage from excess light interception "

it says protective mechanism against damage from EXCESS light. That doesn’t sound like it’s trying to get more light
 

cobshopgrow

Well-Known Member
i have no clue why this rosette want to go horizontal instead of vertical like the other named plants.
maybe its picked cause its the exeption of the rule.

for me shade avoiding plant and protective mechanism dont exclude each other.
understood it as you "trying to avoid more light" intensity, not wanting more intensity.
in general these kind of mentioned plants avoid shade, they still can have too much and show it with leaves going vertical.
by doing this they collect less photons and also let more red light reaching lower leaves which had been shaded before.
thats my understanding of it.
shade itself is detected also by the ratio of far red to red by the plant.
in the end leaves arent digital, a certain leaf inclination is normal and needed.
 
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Tuned

Well-Known Member

I grow tropical brugmansia plants outdoors in the summer months and they point their leaves up every evening. From horizontal to vertical in a matter of minutes. One theory is the plant is keeping the new growth tips warm. So it might be a temp reaction as well as light.
 

cobshopgrow

Well-Known Member

I grow tropical brugmansia plants outdoors in the summer months and they point their leaves up every evening. From horizontal to vertical in a matter of minutes. One theory is the plant is keeping the new growth tips warm. So it might be a temp reaction as well as light.
is that maybe when the sun is below the horizon or near to it, dawn, much far red?
 
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