AOBPreview originally published online on July 15, 2005
Annals of Botany 2005 96(4):581-589; doi:10.1093/aob/mci212
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
REVIEW |
Underwater Photosynthesis in Flooded Terrestrial Plants: A Matter of Leaf Plasticity
Department of Experimental Plant Ecology, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
* For correspondence. E-mail L.Mommer{at}science.ru.nl
Received: 15 November 2004 Returned for revision: 20 January 2005 Accepted: 14 February 2005 Published electronically: 15 July 2005
• Background Flooding causes substantial stress for terrestrial plants, particularly if the floodwater completely submerges the shoot. The main problems during submergence are shortage of oxygen due to the slow diffusion rates of gases in water, and depletion of carbohydrates, which is the substrate for respiration. These two factors together lead to loss of biomass and eventually death of the submerged plants. Although conditions under water are unfavourable with respect to light and carbon dioxide supply, photosynthesis may provide both oxygen and carbohydrates, resulting in continuation of aerobic respiration.
• Scope This review focuses on evidence in the literature that photosynthesis contributes to survival of terrestrial plants during complete submergence. Furthermore, we discuss relevant morphological and physiological responses of the shoot of terrestrial plant species that enable the positive effects of light on underwater plant performance.
• Conclusions Light increases the survival of terrestrial plants under water, indicating that photosynthesis commonly occurs under these submerged conditions. Such underwater photosynthesis increases both internal oxygen concentrations and carbohydrate contents, compared with plants submerged in the dark, and thereby alleviates the adverse effects of flooding. Additionally, several terrestrial species show high plasticity with respect to their leaf development. In a number of species, leaf morphology changes in response to submergence, probably to facilitate underwater gas exchange. Such increased gas exchange may result in higher assimilation rates, and lower carbon dioxide compensation points under water, which is particularly important at the low carbon dioxide concentrations observed in the field. As a result of higher internal carbon dioxide concentrations in submergence-acclimated plants, underwater photorespiration rates are expected to be lower than in non-acclimated plants. Furthermore, the regulatory mechanisms that induce the switch from terrestrial to submergence-acclimated leaves may be controlled by the same pathways as described for heterophyllous aquatic plants.
Key words: Flooding, gas exchange, heterophylly, hormonal regulation, leaf morphology, phenotypic plasticity, photorespiration, photosynthesis, Rumex, submergence, survival, wetlands
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  G. G. Striker, P. Insausti, and A. A. Grimoldi Flooding Effects on Plants Recovering from Defoliation in Paspalum dilatatum and Lotus tenuis Ann. Bot., August 1, 2008; 102(2): 247 - 254. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. B. Jackson Ethylene-promoted Elongation: an Adaptation to Submergence Stress Ann. Bot., January 1, 2008; 101(2): 229 - 248. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Mommer, T. L. Pons, and E. J. W. Visser Photosynthetic consequences of phenotypic plasticity in response to submergence: Rumex palustris as a case study J. Exp. Bot., January 1, 2006; 57(2): 283 - 290. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. B. JACKSON and T. D. COLMER Response and Adaptation by Plants to Flooding Stress Ann. Bot., September 1, 2005; 96(4): 501 - 505. [Abstract] [Full Text] [PDF]
|
|