Abstract
Theory is developed to explain the carbon isotopic composition of plants with the dicarboxylic acid (C4) pathway of carbon fixation. It is shown how leakage of inorganic carbon from the bundle sheath cells to the mesophyll cells can affect carbon isotopic discrimination. It is suggested that different types of C4 pathways will show variation in the degree of leakiness, reflecting variations in anatomy, and in the requirements for oxygen egress from the bundle sheath cells. It is also suggested that quantum yields may reflect these variations. A simplified expression is developed relating discrimination to leakiness and the ratio of intercellular and atmospheric partial pressures of CO2.
Keywords
BiologyCarbon fixationIsotopes of carbonCarbon fibersEcophysiologyFixation (population genetics)BiophysicsPlant biologyVascular bundleBundleBotanyPhotosynthesisEcologyGeneBiochemistryMaterials scienceTotal organic carbon
Related Publications
Carbon Isotope Discrimination measured Concurrently with Gas Exchange to Investigate CO2 Diffusion in Leaves of Higher Plants
Conventional gas-exchange techniques that measure the stomatal conductance and rate of CO2 assimilation of leaves were combined with measurements of the carbon isotope compositi...
Diffusion of CO<sub>2</sub>and other gases inside leaves
SUMMARY Diffusion of CO 2 in the intercellular airspaces of the leaf mesophyll is one of the many processes that can limit photosynthetic carbon assimilation there. This limitat...
Solubility of gases and the temperature dependency of whole leaf affinities for carbon dioxide and oxygen: an alternative perspective.
An analysis of the kinetics of simultaneous photosynthesis and photorespiration at the end of a diffusion path is applied to observed net photosynthetic rate as a function of O(...
Gas Exchange, Stomatal Behavior, and δ<sup>13</sup>C Values of the <i>flacca</i> Tomato Mutant in Relation to Abscisic Acid
The relationship between stomatal conductance and capacity for assimilation was investigated in flacca, a mutant of tomato (Lycopersicon esculentum Mill.) that has abnormal stom...
Effect of Varying CO<sub>2</sub> Partial Pressure on Photosynthesis and on Carbon Isotope Composition of Carbon-4 of Malate from the Crassulacean Acid Metabolism Plant <i>Kalanchoë daigremontiana</i> Hamet et Perr.
Intact leaves of Kalanchoë daigremontiana were exposed to CO(2) partial pressures of 100, 300, and 1000 microbars. Malic acid was extracted, purified, and degraded in order to o...
Publication Info
- Year
- 1983
- Type
- article
- Volume
- 10
- Issue
- 2
- Pages
- 205-226
- Citations
- 570
- Access
- Closed
External Links
Social Impact
Altmetric
PlumX Metrics
Social media, news, blog, policy document mentions
Citation Metrics
570
OpenAlex
Cite This
Graham D. Farquhar
(1983).
On the Nature of Carbon Isotope Discrimination in C4 Species.
Australian Journal of Plant Physiology
, 10
(2)
, 205-226.
https://doi.org/10.1071/pp9830205
Identifiers
- DOI
- 10.1071/pp9830205