δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2
Post-photosynthetic carbon isotope fractionation might alter the isotopic signal imprinted on organic matter (OM) during primary carbon fixation by Rubisco. To characterise the influence of post-photosynthetic processes, we investigated the effect of starch storage and remobilisation on the stable c...
| Main Authors: | , , , , , , , , |
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| Format: | Journal Article |
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CSIRO Publishing
2007
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| Online Access: | http://hdl.handle.net/20.500.11937/45098 |
| _version_ | 1848757188528439296 |
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| author | Gessler, A. Keitel, C. Kodama, N. Weston, C. Winters, A. Keith, H. Grice, Kliti Leuning, R. Farquhar, G. |
| author_facet | Gessler, A. Keitel, C. Kodama, N. Weston, C. Winters, A. Keith, H. Grice, Kliti Leuning, R. Farquhar, G. |
| author_sort | Gessler, A. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Post-photosynthetic carbon isotope fractionation might alter the isotopic signal imprinted on organic matter (OM) during primary carbon fixation by Rubisco. To characterise the influence of post-photosynthetic processes, we investigated the effect of starch storage and remobilisation on the stable carbon isotope signature (delta C-13) of different carbon pools in the Eucalyptus delegatensis R. T. Baker leaf and the potential carbon isotope fractionation associated with phloem transport and respiration. Twig phloem exudate and leaf water-soluble OM showed diel variations in delta C-13 of up to 2.5 and 2 parts per thousand, respectively, with C-13 enrichment during the night and depletion during the day. Damped diel variation was also evident in bulk lipids of the leaf and in the leaf wax fraction. delta C-13 of nocturnal phloem exudate OM corresponded with the delta C-13 of carbon released from starch. There was no change in delta C-13 of phloem carbon along the trunk. CO2 emitted from trunks and roots was C-13 enriched compared with the potential organic substrate, and depleted compared with soil-emitted CO2. The results are consistent with transitory starch accumulation and remobilisation governing the diel rhythm of delta C-13 in phloem-transported OM and fragmentation fractionation occurring during respiration. When using delta C-13 of OMor CO2 for assessing ecosystem processes or plant reactions towards environmental constraints, post- photosynthetic discrimination should be considered. |
| first_indexed | 2025-11-14T09:24:07Z |
| format | Journal Article |
| id | curtin-20.500.11937-45098 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:24:07Z |
| publishDate | 2007 |
| publisher | CSIRO Publishing |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-450982017-11-02T07:08:06Z δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 Gessler, A. Keitel, C. Kodama, N. Weston, C. Winters, A. Keith, H. Grice, Kliti Leuning, R. Farquhar, G. phloem transported organic matter isotope discrimination fragmentation fractionation post-photosynthetic carbon starch Post-photosynthetic carbon isotope fractionation might alter the isotopic signal imprinted on organic matter (OM) during primary carbon fixation by Rubisco. To characterise the influence of post-photosynthetic processes, we investigated the effect of starch storage and remobilisation on the stable carbon isotope signature (delta C-13) of different carbon pools in the Eucalyptus delegatensis R. T. Baker leaf and the potential carbon isotope fractionation associated with phloem transport and respiration. Twig phloem exudate and leaf water-soluble OM showed diel variations in delta C-13 of up to 2.5 and 2 parts per thousand, respectively, with C-13 enrichment during the night and depletion during the day. Damped diel variation was also evident in bulk lipids of the leaf and in the leaf wax fraction. delta C-13 of nocturnal phloem exudate OM corresponded with the delta C-13 of carbon released from starch. There was no change in delta C-13 of phloem carbon along the trunk. CO2 emitted from trunks and roots was C-13 enriched compared with the potential organic substrate, and depleted compared with soil-emitted CO2. The results are consistent with transitory starch accumulation and remobilisation governing the diel rhythm of delta C-13 in phloem-transported OM and fragmentation fractionation occurring during respiration. When using delta C-13 of OMor CO2 for assessing ecosystem processes or plant reactions towards environmental constraints, post- photosynthetic discrimination should be considered. 2007 Journal Article http://hdl.handle.net/20.500.11937/45098 10.1071/FP07064 CSIRO Publishing restricted |
| spellingShingle | phloem transported organic matter isotope discrimination fragmentation fractionation post-photosynthetic carbon starch Gessler, A. Keitel, C. Kodama, N. Weston, C. Winters, A. Keith, H. Grice, Kliti Leuning, R. Farquhar, G. δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title | δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title_full | δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title_fullStr | δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title_full_unstemmed | δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title_short | δ13C of organic matter transported from the leaves to the roots in Eucalyptus delegatensis: short-term variations and relation to respired CO2 |
| title_sort | δ13c of organic matter transported from the leaves to the roots in eucalyptus delegatensis: short-term variations and relation to respired co2 |
| topic | phloem transported organic matter isotope discrimination fragmentation fractionation post-photosynthetic carbon starch |
| url | http://hdl.handle.net/20.500.11937/45098 |