Production Practices and Quality Assessment of Food Crops. Vol. 1

on an analysis of the biophysical processes, it can easily be used in a larger framework
than fruit growth. It can be used to simulate concentration in total soluble
sugars which is an essential feature of fruit quality. It can also be used to study other
aspects of fruit quality such as the occurrence of blossom-end rot which is one of
the main physiological disorders of greenhouse pepper. This disorder is considered
as the result of low calcium concentrations. The SWAF model has been used
to simulate calcium accumulation in the fruit considering that calcium is transported
in the xylem by mass flow (Bar-Tal et al., 1999).
4.1.2. SUGAR: a metabolic model of fruit sweetness
Modelling Fruit Quality 55
Figure 2. Patterns of 5 days (105–109th days after bloom) simulations obtained with SWAF under
normal irrigation and light crop load conditions. The upper graph represents dry flesh mass increase
in peach. The second graph shows the changes calculated in fresh mass compared to the calculated peach
transpiration, hydrostatic pressure and water balance.
Many studies on the sugar content of fleshy fruits have focused on compositional
changes during fruit growth and maturation (Ishida et al., 1971; Chapman et al.,