title: Modelling fruit-temperature dynamics within apple tree crowns using virtual plants.
abstract: OBJECTIVE
  Fruit temperature results from a complex system involving the climate, the tree architecture, the fruit location within the tree crown and the fruit thermal properties. Despite much theoretical and experimental evidence for large differences (up to 10 °C in sunny conditions) between fruit temperature and air temperature, fruit temperature is never used in horticultural studies. A way of modelling fruit-temperature dynamics from climate data is addressed in this work.
  
  
  METHODS
  The model is based upon three-dimensional virtual representation of apple trees and links three-dimensional virtual trees with a physical-based fruit-temperature dynamical model. The overall model was assessed by comparing model outputs to field measures of fruit-temperature dynamics.
  
  
  RESULTS
  The model was able to simulate both the temperature dynamics at fruit scale, i.e. fruit-temperature gradients and departure from air temperature, and at the tree scale, i.e. the within-tree-crown variability in fruit temperature (average root mean square error value over fruits was 1·43 °C).
  
  
  CONCLUSIONS
  This study shows that linking virtual plants with the modelling of the physical plant environment offers a relevant framework to address the modelling of fruit-temperature dynamics within a tree canopy. The proposed model offers opportunities for modelling effects of the within-crown architecture on fruit thermal responses in horticultural studies.
authors.affiliation: INRA, UMR 547 PIAF, F-63000 Clermont-Ferrand, France. marc.saudreau@clermont.inra.fr
authors.forename: M
authors.initials: M
authors.lastname: Saudreau
authors.forename: A
authors.initials: A
authors.lastname: Marquier
authors.forename: B
authors.initials: B
authors.lastname: Adam
authors.forename: H
authors.initials: H
authors.lastname: Sinoquet
mesh_terms: D000388:Air; D003198:Computer Simulation; D005638:Fruit / Q000502:physiology*; D021621:Imaging, Three-Dimensional; D008027:Light; D016014:Linear Models; D027845:Malus / Q000502:physiology*; D008834:Microclimate; D008954:Models, Biological; D018515:Plant Leaves / Q000502:physiology; D018526:Plant Transpiration; D013696:Temperature