Hydrodynamics of steady state phloem transport with radial leakage of solute
Long-distance phloem transport occurs under a pressure gradient generated by the osmotic exchange of water associated with solute exchange in source and sink regions. But these exchanges also occur along the pathway, and yet their physiological role has almost been ignored in mathematical models of...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2013-12-01
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| Series: | Frontiers in Plant Science |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fpls.2013.00531/full |
| _version_ | 1818993255935639552 |
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| author | Paulo eCabrita Michael eThorpe Michael eThorpe Gregor Johannes Huber |
| author_facet | Paulo eCabrita Michael eThorpe Michael eThorpe Gregor Johannes Huber |
| author_sort | Paulo eCabrita |
| collection | DOAJ |
| description | Long-distance phloem transport occurs under a pressure gradient generated by the osmotic exchange of water associated with solute exchange in source and sink regions. But these exchanges also occur along the pathway, and yet their physiological role has almost been ignored in mathematical models of phloem transport. Here we present a steady state model for transport phloem which allows solute leakage, based on the Navier-Stokes and convection-diffusion equations which describe fluid motion rigorously. Sieve tube membrane permeability Ps for passive solute exchange (and correspondingly, membrane reflection coefficient) influenced model results strongly, and had to lie in the bottom range of the values reported for plant cells for the results to be realistic. This smaller permeability reflects the efficient specialization of sieve tube elements, minimizing any diffusive solute loss favoured by the large concentration difference across the sieve tube membrane. We also found there can be a specific reflection coefficient for which pressure profiles and sap velocities can both be similar to those predicted by the Hagen-Poiseuille equation for a completely impermeable tube. |
| first_indexed | 2024-12-20T20:39:09Z |
| format | Article |
| id | doaj.art-ad89e0cdcf4c4ba6a5e29e4538d026b6 |
| institution | Directory Open Access Journal |
| issn | 1664-462X |
| language | English |
| last_indexed | 2024-12-20T20:39:09Z |
| publishDate | 2013-12-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Plant Science |
| spelling | doaj.art-ad89e0cdcf4c4ba6a5e29e4538d026b62022-12-21T19:27:09ZengFrontiers Media S.A.Frontiers in Plant Science1664-462X2013-12-01410.3389/fpls.2013.0053169156Hydrodynamics of steady state phloem transport with radial leakage of solutePaulo eCabrita0Michael eThorpe1Michael eThorpe2Gregor Johannes Huber3Forschungszentrum Jülich GmbHForschungszentrum Jülich GmbHAustralina National UniversityForschungszentrum Jülich GmbHLong-distance phloem transport occurs under a pressure gradient generated by the osmotic exchange of water associated with solute exchange in source and sink regions. But these exchanges also occur along the pathway, and yet their physiological role has almost been ignored in mathematical models of phloem transport. Here we present a steady state model for transport phloem which allows solute leakage, based on the Navier-Stokes and convection-diffusion equations which describe fluid motion rigorously. Sieve tube membrane permeability Ps for passive solute exchange (and correspondingly, membrane reflection coefficient) influenced model results strongly, and had to lie in the bottom range of the values reported for plant cells for the results to be realistic. This smaller permeability reflects the efficient specialization of sieve tube elements, minimizing any diffusive solute loss favoured by the large concentration difference across the sieve tube membrane. We also found there can be a specific reflection coefficient for which pressure profiles and sap velocities can both be similar to those predicted by the Hagen-Poiseuille equation for a completely impermeable tube.http://journal.frontiersin.org/Journal/10.3389/fpls.2013.00531/fullPhloem transportFluid DynamicsHydrodynamicssieve tubeNavier-StokesSolute Exchange |
| spellingShingle | Paulo eCabrita Michael eThorpe Michael eThorpe Gregor Johannes Huber Hydrodynamics of steady state phloem transport with radial leakage of solute Frontiers in Plant Science Phloem transport Fluid Dynamics Hydrodynamics sieve tube Navier-Stokes Solute Exchange |
| title | Hydrodynamics of steady state phloem transport with radial leakage of solute |
| title_full | Hydrodynamics of steady state phloem transport with radial leakage of solute |
| title_fullStr | Hydrodynamics of steady state phloem transport with radial leakage of solute |
| title_full_unstemmed | Hydrodynamics of steady state phloem transport with radial leakage of solute |
| title_short | Hydrodynamics of steady state phloem transport with radial leakage of solute |
| title_sort | hydrodynamics of steady state phloem transport with radial leakage of solute |
| topic | Phloem transport Fluid Dynamics Hydrodynamics sieve tube Navier-Stokes Solute Exchange |
| url | http://journal.frontiersin.org/Journal/10.3389/fpls.2013.00531/full |
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