|
PLANT PHYSIOLOGY , Vol 113, Issue 4 1283-1292, Copyright © 1997 by American Society of Plant Biologists
|
WHOLE PLANT, ENVIRONMENTAL, AND STRESS PHYSIOLOGY |
Discrimination Processes and Shifts in Carboxylation during the Phases of Crassulacean Acid Metabolism
A. Roberts, A. M. Borland and H. Griffiths
Department of Agricultural and Environmental Science, Ridley Building, Claremont Road, The University of Newcastle, Newcastle-Upon-Tyne NE1 7RU, United Kingdom
The magnitude and extent of Crassulacean acid metabolism (CAM) activity in
two Clusia species was manipulated to investigate the regulation of the
distinct CAM phases. First, in response to leaf-air vapor pressure deficit
at night, changes in leaf conductance altered on-line carbon-isotope
discrimination throughout the theoretical range for dark CO2 uptake during
CAM. These ranged from the limit set by phosphoenolpyruvate carboxylase
(PEPc) (-6[per mille (thousand) sign], [delta]13C equivalent of -2[per
mille (thousand) sign]) to that imposed by diffusion limitation (+4[per
mille (thousand) sign], [delta]13C equivalent of -12[per mille (thousand)
sign]), but the lowest carbon-isotope discrimination occurred when P[square
root]pa was only 0.7. Second, when the availability of external or internal
sources of CO2 was reduced for both field- and greenhouse-grown plants, CO2
uptake by day via PEPc during phase II largely compensated. Third, by
reducing the dark period, plants accumulated low levels of acidity, and CO2
uptake occurred throughout the subsequent light period. Discrimination
switched from being dominated by PEPc (phase II) to ribulose
1,5-bisphosphate carboxylase/oxygenase (phase III), with both enzymes
active during phase IV. Under natural conditions, photochemical stability
is maintained by extended PEPc activity in phase II, which enhances acid
accumulation and delays decarboxylation until temperature and light stress
are maximal at midday.
This article has been cited by other articles:
|
|
|
|
 
A. M. Borland, H. Griffiths, J. Hartwell, and J. A. C. Smith
Exploiting the potential of plants with crassulacean acid metabolism for bioenergy production on marginal lands
J. Exp. Bot.,
July 1, 2009;
60(10):
2879 - 2896.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. Winter, M. Garcia, and J. A. M. Holtum
Canopy CO2 exchange of two neotropical tree species exhibiting constitutive and facultative CAM photosynthesis, Clusia rosea and Clusia cylindrica
J. Exp. Bot.,
July 1, 2009;
60(11):
3167 - 3177.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
E. A. Nelson and R. F. Sage
Functional constraints of CAM leaf anatomy: tight cell packing is associated with increased CAM function across a gradient of CAM expression
J. Exp. Bot.,
May 1, 2008;
59(7):
1841 - 1850.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. B. Skillman
Quantum yield variation across the three pathways of photosynthesis: not yet out of the dark
J. Exp. Bot.,
May 1, 2008;
59(7):
1647 - 1661.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Griffiths, W. E. Robe, J. Girnus, and K. Maxwell
Leaf succulence determines the interplay between carboxylase systems and light use during Crassulacean acid metabolism in Kalanchoe species
J. Exp. Bot.,
May 1, 2008;
59(7):
1851 - 1861.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
O. Hernandez-Gonzalez and O. B. Villarreal
Crassulacean acid metabolism photosynthesis in columnar cactus seedlings during ontogeny: the effect of light on nocturnal acidity accumulation and chlorophyll fluorescence
Am. J. Botany,
August 1, 2007;
94(8):
1344 - 1351.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Griffiths, A. B. Cousins, M. R. Badger, and S. von Caemmerer
Discrimination in the Dark. Resolving the Interplay between Metabolic and Physical Constraints to Phosphoenolpyruvate Carboxylase Activity during the Crassulacean Acid Metabolism Cycle
Plant Physiology,
February 1, 2007;
143(2):
1055 - 1067.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. M. Borland and T. Taybi
Synchronization of metabolic processes in plants with Crassulacean acid metabolism
J. Exp. Bot.,
June 1, 2004;
55(400):
1255 - 1265.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. N. Dodd, A. M. Borland, R. P. Haslam, H. Griffiths, and K. Maxwell
Crassulacean acid metabolism: plastic, fantastic
J. Exp. Bot.,
April 1, 2002;
53(369):
569 - 580.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. R. Watling, M. C. Press, and W. P. Quick
Elevated CO2 Induces Biochemical and Ultrastructural Changes in Leaves of the C4 Cereal Sorghum
Plant Physiology,
July 1, 2000;
123(3):
1143 - 1152.
[Abstract]
[Full Text]
|
|
|
|
|
|
|
K. Maxwell, A. M. Borland, R. P. Haslam, B. R. Helliker, A. Roberts, and H. Griffiths
Modulation of Rubisco Activity during the Diurnal Phases of the Crassulacean Acid Metabolism Plant Kalanchoe daigremontiana
Plant Physiology,
November 1, 1999;
121(3):
849 - 856.
[Abstract]
[Full Text]
|
|
|
|
|
