Only early morning and evening when the sun sneaks under the staging, but it still colours up the seedlings.
Turbinicarpus laui
Turbinicarpus valdezianus
Ariocarpus fissuratus
Mammillaria grahamii
Cactus seedlings in the sun
Forum rules
For the discussion of topics related to the conservation, cultivation, propagation, exhibition & science of cacti & other succulents only.
Please respect all forum members opinions and if you can't make a civil reply, don't reply!
For the discussion of topics related to the conservation, cultivation, propagation, exhibition & science of cacti & other succulents only.
Please respect all forum members opinions and if you can't make a civil reply, don't reply!
- iann
- BCSS Member
- Posts: 14565
- https://www.behance.net/kuchnie-warszawa
- Joined: 11 Jan 2007
- Branch: MACCLESFIELD & EAST CHESHIRE
- Country: UK
- Role within the BCSS: Member
Cactus seedlings in the sun
Cheshire, UK
- ralphrmartin
- BCSS Research Committee Chairman
- Posts: 6070
- Joined: 11 Jan 2007
- Branch: None
- Country: United Kingdom
- Role within the BCSS: Chairman - Research
- Location: Pwllheli
- Contact:
Re: Cactus seedlings in the sun
Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
Ralph Martin
https://www.rrm.me.uk/Cacti/cacti.html
Members visiting the Llyn Peninsula are welcome to visit my collection.
Swaps and sales at https://www.rrm.me.uk/Cacti/forsale.php
My Field Number Database is at https://www.fieldnos.bcss.org.uk
https://www.rrm.me.uk/Cacti/cacti.html
Members visiting the Llyn Peninsula are welcome to visit my collection.
Swaps and sales at https://www.rrm.me.uk/Cacti/forsale.php
My Field Number Database is at https://www.fieldnos.bcss.org.uk
- el48tel
- BCSS Member
- Posts: 5320
- Joined: 04 Aug 2018
- Branch: LEEDS
- Country: UK
- Role within the BCSS: Member
- Location: Leeds
Re: Cactus seedlings in the sun
Not green means a lower level of chlorophyll in the plant in proportion to the other pigments which are red through yellow in colour.
Endeavouring to grow Aylostera, Echinocereus, Echinopsis, Gymnocalycium, Matucana, Rebutia, and Sulcorebutia. Fallen out of love with Lithops and aggravated by Aeoniums.
Currently being wooed by Haworthia, attempting hybridisation, and enticed by Mesembs.
Currently being wooed by Haworthia, attempting hybridisation, and enticed by Mesembs.
-
- BCSS Member
- Posts: 2871
- Joined: 09 Dec 2019
- Branch: None
- Country: United Kingdom
- Role within the BCSS: Member
Re: Cactus seedlings in the sun
If I remember my plant physiology lectures correctly, some red pigments lie on top of green chlorophyll to act as sunscreen whereas some plants have different photosynthetic pathways using red pigments as the trees above have filtered out almost all of the green light so they photosynthesise using the red light.ralphrmartin wrote: ↑Sun Jun 14, 2020 4:11 pm Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
Ed
BCSS member 53038
BCSS member 53038
-
- BCSS Member
- Posts: 53
- Joined: 19 Jul 2017
- Branch: None
- Country: UK
- Role within the BCSS: Member
Re: Cactus seedlings in the sun
The reason advanced by David Attenborough for the red undersides is that it is a mechanism to reflect light that has passed through the leaf thickness and would otherwise be lost, so the plant gets a second bite at it. Presumably red colouration in seedlings is, as you say, protection against damage.ralphrmartin wrote: ↑Sun Jun 14, 2020 4:11 pm Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
-
- BCSS Member
- Posts: 2871
- Joined: 09 Dec 2019
- Branch: None
- Country: United Kingdom
- Role within the BCSS: Member
Re: Cactus seedlings in the sun
I don't by the looks of a bit of research! The phytochrome detects the far red light and then encourages greater concentrations of chlorophyll b.edds wrote: ↑Sun Jun 14, 2020 5:01 pmIf I remember my plant physiology lectures correctly, some red pigments lie on top of green chlorophyll to act as sunscreen whereas some plants have different photosynthetic pathways using red pigments as the trees above have filtered out almost all of the green light so they photosynthesise using the red light.ralphrmartin wrote: ↑Sun Jun 14, 2020 4:11 pm Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
Ed
BCSS member 53038
BCSS member 53038
- Chris L
- BCSS Branch Websites Co-ordinator
- Posts: 2609
- Joined: 11 Oct 2009
- Branch: MANCHESTER
- Country: England
- Role within the BCSS: Branch Websites Co-ordinator
- Location: Lancashire, England
- Contact:
Re: Cactus seedlings in the sun
Since many leaves are slightly transparent when held upto the light maybe the light has shone through the leaves and burnt the other side.ralphrmartin wrote: ↑Sun Jun 14, 2020 4:11 pm Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
Joined 1991
Lamb's Reference Plate Index http://www.cactus-corner.co.uk/referenc ... -guide.htm
FREE on Kindle Unlimited:
Anglesey Circular Walk https://amzn.to/34i18qF
Lytham-Arnside Walk https://amzn.to/3fpQPGf
My Redbubble Shop https://www.redbubble.com/people/cactuschris/shop
Lamb's Reference Plate Index http://www.cactus-corner.co.uk/referenc ... -guide.htm
FREE on Kindle Unlimited:
Anglesey Circular Walk https://amzn.to/34i18qF
Lytham-Arnside Walk https://amzn.to/3fpQPGf
My Redbubble Shop https://www.redbubble.com/people/cactuschris/shop
- el48tel
- BCSS Member
- Posts: 5320
- Joined: 04 Aug 2018
- Branch: LEEDS
- Country: UK
- Role within the BCSS: Member
- Location: Leeds
Re: Cactus seedlings in the sun
Yes ... the structure of the plant has different pigments at different levels. Surprisingly, the infrared reflectance of cactus and succulents is very high compared to native UK plants.edds wrote: ↑Sun Jun 14, 2020 5:01 pmIf I remember my plant physiology lectures correctly, some red pigments lie on top of green chlorophyll to act as sunscreen whereas some plants have different photosynthetic pathways using red pigments as the trees above have filtered out almost all of the green light so they photosynthesise using the red light.ralphrmartin wrote: ↑Sun Jun 14, 2020 4:11 pm Here's something I find intriguing. When cactus seedlings get too much sun, they go red. Yet plants on the forest floor often have red underleaves. In one case red seems like a reaction to excess light, and in the other case to a lack of light. Why red in each case?
Endeavouring to grow Aylostera, Echinocereus, Echinopsis, Gymnocalycium, Matucana, Rebutia, and Sulcorebutia. Fallen out of love with Lithops and aggravated by Aeoniums.
Currently being wooed by Haworthia, attempting hybridisation, and enticed by Mesembs.
Currently being wooed by Haworthia, attempting hybridisation, and enticed by Mesembs.
- ralphrmartin
- BCSS Research Committee Chairman
- Posts: 6070
- Joined: 11 Jan 2007
- Branch: None
- Country: United Kingdom
- Role within the BCSS: Chairman - Research
- Location: Pwllheli
- Contact:
Re: Cactus seedlings in the sun
Not sure what wavelengths you mean, but go far enough into infrared and you are talking of heat rays. I'm not surprised that cacti want to reflect heat rays, while British plants want to soak up the sun most of the year, if indeed those are the wavelengths you mean.
Ralph Martin
https://www.rrm.me.uk/Cacti/cacti.html
Members visiting the Llyn Peninsula are welcome to visit my collection.
Swaps and sales at https://www.rrm.me.uk/Cacti/forsale.php
My Field Number Database is at https://www.fieldnos.bcss.org.uk
https://www.rrm.me.uk/Cacti/cacti.html
Members visiting the Llyn Peninsula are welcome to visit my collection.
Swaps and sales at https://www.rrm.me.uk/Cacti/forsale.php
My Field Number Database is at https://www.fieldnos.bcss.org.uk
Re: Cactus seedlings in the sun
Interesting topic.
Ralph are those Ariocarpus out of humidity now?
Ralph are those Ariocarpus out of humidity now?