This title appears in the Scientific Report :
2005
Please use the identifier:
http://dx.doi.org/10.1071/FP05082 in citations.
Short-term storage of carbohydrate in stem tissue of apple (Malus domestica), a woody perennial: evidence for involvement of the apoplast
Short-term storage of carbohydrate in stem tissue of apple (Malus domestica), a woody perennial: evidence for involvement of the apoplast
This work investigates the pathway and mechanism for lateral retrieval of carbohydrate into the transport phloem of apple stems ( Malus domestica Borkh.). A heat exchanger was set up on the stem, allowing rapid chilling and subsequent re-warming of stem segments while the time course of axial transp...
Saved in:
Personal Name(s): | McQueen, J. C. |
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Minchin, P. E. H. / Thorpe, M. R. / Silvester, W. B. | |
Contributing Institute: |
Phytosphäre; ICG-III |
Published in: | Functional plant biology, 32 (2005) S. 1027 - 1031 |
Imprint: |
Collingwood, Victoria
CSIRO Publ.
2005
|
Physical Description: |
1027 - 1031 |
DOI: |
10.1071/FP05082 |
Document Type: |
Journal Article |
Research Program: |
Chemie und Dynamik der Geo-Biosphäre |
Series Title: |
Functional Plant Biology
32 |
Subject (ZB): | |
Publikationsportal JuSER |
This work investigates the pathway and mechanism for lateral retrieval of carbohydrate into the transport phloem of apple stems ( Malus domestica Borkh.). A heat exchanger was set up on the stem, allowing rapid chilling and subsequent re-warming of stem segments while the time course of axial transport of C-11-labelled photoassimilate was measured at a position similar to 65 mm downstream of the heat exchanger. Whenever axial transport was blocked by a sudden chill at the heat exchanger, transport 65 mm downstream from the blockage immediately slowed but did not stop, showing that there was retrieval of solutes into the pathway ( buffering), within that 65 mm of stem, to help maintain the axial flow. Use of PCMBS, an inhibitor of sugar transporters, showed that the buffering included retrieval of sugar from the apoplast. We concluded that in apple, apoplastic sugar in stem tissue can buffer phloem transport during short-term changes in supply and demand for carbohydrates. Buffering was stronger when mobile reserves in the stem were higher, for example late in the photoperiod, or if carbohydrate demand in the terminal sink was increased. We also suggest that the concentration of sugars in the apoplast is a regulator of carbohydrate storage and re-mobilisation. |