Divergence in δ13C of dark respired CO2 and bulk organic matter occurs during the transition between heterotrophy and autotrophy in Phaseolus vulgaris plants
- 22 October 2007
- journal article
- Published by Wiley in New Phytologist
- Vol. 177 (2), 406-418
- https://doi.org/10.1111/j.1469-8137.2007.02246.x
Abstract
Substantial evidence has been published in recent years demonstrating that postphotosynthetic fractionations occur in plants, leading to (13)C-enrichment in heterotrophic (as compared with autotrophic) organs. However, less is known about the mechanism responsible for changes in these responses during plant development. The isotopic signature of both organic matter and respired CO(2) for different organs of French bean (Phaseolus vulgaris) was investigated during early ontogeny, in order to identify the developmental stage at which isotopic changes occur. Isotopic analyses of metabolites and mass balance calculations helped to constrain the metabolic processes involved. At the plant scale, apparent respiratory fractionation was constantly positive in the heterotrophic phase (c. 1 per thousand) and turned negative with autotrophy acquisition (down to -3.08 per thousand). Initially very close to that of the dry seed (-26.83 +/- 0.69 per thousand), isotopic signatures of organic matter and respired CO(2) diverged (in opposite directions) in leaves and roots after onset of photosynthesis. Respired CO(2) reached values up to -20 per thousand in leaves and became (13)C-depleted down to -29 per thousand in roots. It was concluded that isotopic differences between organs occurred subsequent to metabolic changes in the seedling during the transition from heterotrophy to autotrophy. They were especially related to respiration and respiratory fractionation.Keywords
This publication has 63 references indexed in Scilit:
- Allocation of reserve‐derived and currently assimilated carbon and nitrogen in seedlings of Helianthus annuus under subambient and elevated CO2 growth conditionsNew Phytologist, 2005
- Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditionsOecologia, 2004
- The importance of seed reserves for seedling performance: an integrated approach using morphological, physiological, and stable isotope techniquesOecologia, 2004
- Transition‐state responses to amino acid perturbations in yeast pyruvate decarboxylase: a carbon kinetic isotope effect studyJournal of Physical Organic Chemistry, 2004
- Comparisons of δ13C of photosynthetic products and ecosystem respiratory CO2 and their responses to seasonal climate variabilityOecologia, 2004
- A possible global covariance between terrestrial gross primary production and13C discrimination: Consequences for the atmospheric13C budget and its response to ENSOGlobal Biogeochemical Cycles, 2002
- Carbon economy in walnut seedlings during the acquisition of autotrophy studied by long-term labelling with 13CO2Physiologia Plantarum, 1994
- ATP Production by Respiration and Fermentation, and Energy Charge during Aerobiosis and Anaerobiosis in Twelve Fatty and Starchy Germinating SeedsPlant Physiology, 1985
- Transition between seed reserve use and photosynthetic supply during development of maize seedlingsPlant Science Letters, 1984
- Role of the Testa in Preventing Cellular Rupture During Imbibition of Legume SeedsPlant Physiology, 1981