BACKGROUND: Carbon assimilation and leaf-to-fruit sugar transport are, along with plant water status, the driving mechanisms for fruit growth. An integrated comprehension of the plant water and carbon relationships is therefore essential to better understand water and dry matter accumulation. Variations in stem diameter result from an integrated response to plant water and carbon status and are as such a valuable source of information. METHODS: A mechanistic water flow and storage model was used to relate variations in stem diameter to phloem sugar loading and sugar concentration dynamics in tomato. The simulation results were compared with an independent model, simulating phloem sucrose loading at the leaf level based on photosynthesis and sugar metabolism kinetics and enabled a mechanistic interpretation of the 'one common assimilate pool' concept for tomato. KEY RESULTS: Combining stem diameter variation measurements and mechanistic modelling allowed us to distinguish instantaneous dynamics in the plant water relations and gradual variations in plant carbon status. Additionally, the model combined with stem diameter measurements enabled prediction of dynamic variables which are difficult to measure in a continuous and non-destructive way, such as xylem water potential and phloem hydrostatic potential. Finally, dynamics in phloem sugar loading and sugar concentration were distilled from stem diameter variations. CONCLUSIONS: Stem diameter variations, when used in mechanistic models, have great potential to continuously monitor and interpret plant water and carbon relations under natural growing conditions.
BACKGROUND:Carbon assimilation and leaf-to-fruit sugar transport are, along with plant water status, the driving mechanisms for fruit growth. An integrated comprehension of the plant water and carbon relationships is therefore essential to better understand water and dry matter accumulation. Variations in stem diameter result from an integrated response to plant water and carbon status and are as such a valuable source of information. METHODS: A mechanistic water flow and storage model was used to relate variations in stem diameter to phloem sugar loading and sugar concentration dynamics in tomato. The simulation results were compared with an independent model, simulating phloem sucrose loading at the leaf level based on photosynthesis and sugar metabolism kinetics and enabled a mechanistic interpretation of the 'one common assimilate pool' concept for tomato. KEY RESULTS: Combining stem diameter variation measurements and mechanistic modelling allowed us to distinguish instantaneous dynamics in the plant water relations and gradual variations in plant carbon status. Additionally, the model combined with stem diameter measurements enabled prediction of dynamic variables which are difficult to measure in a continuous and non-destructive way, such as xylem water potential and phloem hydrostatic potential. Finally, dynamics in phloem sugar loading and sugar concentration were distilled from stem diameter variations. CONCLUSIONS: Stem diameter variations, when used in mechanistic models, have great potential to continuously monitor and interpret plant water and carbon relations under natural growing conditions.
Authors: M Génard; N Bertin; C Borel; P Bussières; H Gautier; R Habib; M Léchaudel; A Lecomte; F Lescourret; P Lobit; B Quilot Journal: J Exp Bot Date: 2007-02-05 Impact factor: 6.992
Authors: Maurits W Vandegehuchte; Adrien Guyot; Michiel Hubeau; Tom De Swaef; David A Lockington; Kathy Steppe Journal: Ann Bot Date: 2014-09 Impact factor: 4.357
Authors: Maurizio Mencuccini; Yann Salmon; Patrick Mitchell; Teemu Hölttä; Brendan Choat; Patrick Meir; Anthony O'Grady; David Tissue; Roman Zweifel; Sanna Sevanto; Sebastian Pfautsch Journal: Plant Cell Environ Date: 2017-01-06 Impact factor: 7.228