Leaf window: Difference between revisions
No edit summary |
|||
| Line 4: | Line 4: | ||
==Fuctions== |
==Fuctions== |
||
The primary function of the epidermal window is to increase the absorption of radiant energy, and there by the rate of photosynthesis.<ref>{{Cite journal|last=Egbert|first=K.|date=March 2002|title=The Influence of Leaf Windows on the Utilization and Absorption of Radiant Energy in Seven Desert Succulents|url=http://link.springer.com/article/10.1023%2FA%3A1020129820295|journal=Photosynthetica|doi=10.1023/A:1020129820295|pmid=|access-date=June 10, 2016}}</ref> Epidermal windows are situated at the apex of leaves, allowing unobstructed sunlight to be captured and utilized even when the plant is buried below the surface of the soil. <ref>{{Cite web|url=http://www.cactus-art.biz/note-book/Dictionary/Dictionary_W/dictionary_windowed.htm|title=Windowed|website=www.cactus-art.biz|access-date=2016-06-10}}</ref> The absence of [[Stoma|stomata]] in the transluscent tissue of the window prevents water loss in the plant. This allows succulents to minimize the exposure of leaf surface area to the outside environment and reduce the risk of [[desiccation]] under intense heat. The actual green, photosynthesizing surface is hidden in the underground part of the plant, so that it collects only the diffused light that strikes the windows. Experiments in the [[Lithops]] species of succulents, have shown that the size of leaf windows correlates inversely with habitat [[solar irradiance]].<ref>{{Cite journal|last=Martin|first=C. E.|last2=Brandmeyer|first2=E. A.|last3=Ross|first3=R. D.|date=2013-01-01|title=Ecophysiological function of leaf 'windows' in Lithops species - 'Living Stones' that grow underground|url=http://www.ncbi.nlm.nih.gov/pubmed/23043320|journal=Plant Biology (Stuttgart, Germany)|volume=15|issue=1|pages=243–247|doi=10.1111/j.1438-8677.2012.00672.x|issn=1438-8677|pmid=23043320}}</ref> Epidermal windows of plants growing in regions of high irradiance and low-rainfall were smaller than of those plants which grew in cloudy, high-rainfall regions. It is presumed that the size variation evolved to allow individual plants to set their optimal uptake of sunlight based on its environment. |
The primary function of the epidermal window is to increase the absorption of radiant energy, and there by the rate of photosynthesis.<ref>{{Cite journal|last=Egbert|first=K.|date=March 2002|title=The Influence of Leaf Windows on the Utilization and Absorption of Radiant Energy in Seven Desert Succulents|url=http://link.springer.com/article/10.1023%2FA%3A1020129820295|journal=Photosynthetica|doi=10.1023/A:1020129820295|pmid=|access-date=June 10, 2016}}</ref> Epidermal windows are situated at the apex of leaves, allowing unobstructed sunlight to be captured and utilized even when the plant is buried below the surface of the soil. <ref>{{Cite web|url=http://www.cactus-art.biz/note-book/Dictionary/Dictionary_W/dictionary_windowed.htm|title=Windowed|website=www.cactus-art.biz|access-date=2016-06-10}}</ref> The absence of [[Stoma|stomata]] in the transluscent tissue of the window prevents water loss in the plant. This allows succulents to minimize the exposure of leaf surface area to the outside environment and reduce the risk of [[desiccation]] under intense heat. The actual green, photosynthesizing surface is hidden in the underground part of the plant, so that it collects only the diffused light that strikes the windows, which in turn focusses and channels it to the leaves' inside surface.<ref>{{Cite journal| doi = 10.1093/jxb/ern105| issn = 0022-0957, 1460-2431| volume = 59| issue = 7| pages = 1863–1873| last1 = Egbert| first1 = K. J.| last2 = Martin| first2 = C. E.| last3 = Vogelmann| first3 = T. C.| title = The influence of epidermal windows on the light environment within the leaves of six succulents| journal = Journal of Experimental Botany| accessdate = 2016-08-17| date = 2007-06-19| url = http://jxb.oxfordjournals.org/lookup/doi/10.1093/jxb/ern105}}</ref> Experiments in the [[Lithops]] species of succulents, have shown that the size of leaf windows correlates inversely with habitat [[solar irradiance]].<ref>{{Cite journal|last=Martin|first=C. E.|last2=Brandmeyer|first2=E. A.|last3=Ross|first3=R. D.|date=2013-01-01|title=Ecophysiological function of leaf 'windows' in Lithops species - 'Living Stones' that grow underground|url=http://www.ncbi.nlm.nih.gov/pubmed/23043320|journal=Plant Biology (Stuttgart, Germany)|volume=15|issue=1|pages=243–247|doi=10.1111/j.1438-8677.2012.00672.x|issn=1438-8677|pmid=23043320}}</ref> Epidermal windows of plants growing in regions of high irradiance and low-rainfall were smaller than of those plants which grew in cloudy, high-rainfall regions. It is presumed that the size variation evolved to allow individual plants to set their optimal uptake of sunlight based on its environment. |
||
==Species== |
==Species== |
||
Revision as of 02:00, 17 August 2016
Epidermal window, also called Leaf window, is a specialized leaf structure consisting of a translucent area where sunlight can enter into the interior surfaces of the plant's modified leaf where photosynthesis can occur. This is also known ambiguously as fenestration.[1] The translucent structure can appear as a large continuous patch, a variegated or reticulated region, or as numerous small spots. This structural adaptation is found in certain succulent plants native to arid climates, which allow much of the plant to remain beneath the soil surface where it is protected from desiccation of extreme winds and heat while optimizing the absorption of light by increasing the photosynthetic surface area. Many of the known species containing leaf window are native to South Africa and neighbouring countries.Carnivorous plants can also make use of fenestrations by growing traps (highly modified leaves) which use sunlight to lure and/or confuse insects and increase the effectiveness of the trap.[2]
Fuctions
The primary function of the epidermal window is to increase the absorption of radiant energy, and there by the rate of photosynthesis.[3] Epidermal windows are situated at the apex of leaves, allowing unobstructed sunlight to be captured and utilized even when the plant is buried below the surface of the soil. [4] The absence of stomata in the transluscent tissue of the window prevents water loss in the plant. This allows succulents to minimize the exposure of leaf surface area to the outside environment and reduce the risk of desiccation under intense heat. The actual green, photosynthesizing surface is hidden in the underground part of the plant, so that it collects only the diffused light that strikes the windows, which in turn focusses and channels it to the leaves' inside surface.[5] Experiments in the Lithops species of succulents, have shown that the size of leaf windows correlates inversely with habitat solar irradiance.[6] Epidermal windows of plants growing in regions of high irradiance and low-rainfall were smaller than of those plants which grew in cloudy, high-rainfall regions. It is presumed that the size variation evolved to allow individual plants to set their optimal uptake of sunlight based on its environment.
Species
Genus of plants with numerous species having epidermal windows include:
- Cephalotus spp.
- Conophytum spp.
- Darlingtonia spp.
- Fenestraria spp.
- Frithia spp.
- Haworthia spp.
- Lithops spp.
- Nepenthes spp.; known only from N. klossii and N. aristolochioides.
- Pleiospilos spp.
- Sarracenia spp.
Several other plant species have epidermal windows:
Plants with leaf windows are sometimes known as window plants, though this is also the common name used to refer to Fenestraria rhopalophylla.
References
- ^ The Cambridge Illustrated Glossary of Botanical Terms, Cambridge University Press, 2001
{{citation}}: Unknown parameter|authors=ignored (help) - ^ "Predatory Plant: Lure of the Cobra Lily". KQED Science. Retrieved 2016-06-10.
- ^ Egbert, K. (March 2002). "The Influence of Leaf Windows on the Utilization and Absorption of Radiant Energy in Seven Desert Succulents". Photosynthetica. doi:10.1023/A:1020129820295. Retrieved June 10, 2016.
- ^ "Windowed". www.cactus-art.biz. Retrieved 2016-06-10.
- ^ Egbert, K. J.; Martin, C. E.; Vogelmann, T. C. (2007-06-19). "The influence of epidermal windows on the light environment within the leaves of six succulents". Journal of Experimental Botany. 59 (7): 1863–1873. doi:10.1093/jxb/ern105. ISSN 1460-2431 0022-0957, 1460-2431. Retrieved 2016-08-17.
{{cite journal}}: Check|issn=value (help) - ^ Martin, C. E.; Brandmeyer, E. A.; Ross, R. D. (2013-01-01). "Ecophysiological function of leaf 'windows' in Lithops species - 'Living Stones' that grow underground". Plant Biology (Stuttgart, Germany). 15 (1): 243–247. doi:10.1111/j.1438-8677.2012.00672.x. ISSN 1438-8677. PMID 23043320.