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Modelling phloem transport within a pruned dwarf bean: a 2-source-3-sink system.
Michael R Thorpe1, Andr Lacointe2, Peter E H Minchin3
1Phytosphere Institute (ICG-3), Forschungszentrum Jülich, 52425 Jülich, Germany.
Functional Plant Biology : FPB
|June 3, 2020
Summary
A new model accurately predicted carbon transport in bean plants. Bidirectional phloem flow was observed, requiring model adjustments for complex plant architectures.
Area of Science:
- Plant Physiology
- Computational Biology
Background:
- Understanding carbon partitioning is crucial for plant growth and development.
- The Münch hypothesis explains phloem transport, but its application in complex plant architectures requires validation.
Purpose of the Study:
- To test a mechanistic carbon partitioning model (PIAF-Münch) in a complex plant architecture.
- To investigate photosynthate transport dynamics in response to altered source and sink activities.
Main Methods:
- Utilized a mechanistic model based on the Münch hypothesis and the PIAF-Münch platform.
- Employed 11C radiotracer to label photosynthate in a pruned dwarf bean plant (Phaseolus vulgaris L.).
- Compared experimental observations of photosynthate transport with model predictions under varying source/sink conditions.
Main Results:
- The model successfully predicted observed treatment responses in photosynthate transport.
- Tracer detected in both shoot apex and root from a single labeled leaf indicated bidirectional phloem flow.
- The model could be adapted to incorporate bidirectional flow with minor architectural modifications.
Conclusions:
- The PIAF-Münch model effectively explains carbon partitioning in complex plant structures.
- The model platform is suitable for describing photosynthate transport in even more intricate plant architectures.
- Bidirectional phloem transport is a key factor in understanding whole-plant carbon allocation.
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