© 2007 Heron Publishing—Victoria, Canada
An analysis of elastic and plastic fruit growth of mango in response to various assimilate supplies
Mathieu Lechaudel (1, 2), Gilles Vercambre (3), Françoise Lescourret (3), Frederic Normand (1) and Michel Génard (3)
1. Centre de Coopération Internationale en Recherches Agronomique pour le Développement, Département des Productions Fruitières
et Horticoles, Station Bassin Plat, BP 180, 97455 Saint Pierre Cedex, Ile de la Réunion, France / 2. Corresponding author (lechaudel@cirad.fr) / 3. INRA-PSH, Domaine St Paul, 84914 Avignon Cedex 9, France / Received February 27, 2006; accepted April 3, 2006; published online November 1, 2006
Summary
Changes in elastic and plastic components of mango (Mangifera indica L. cv ‘Cogshall’) fruit growth were analyzed with a model of fruit growth over time and in response to various assimilate
supplies. The model is based on water relations (water potential and osmotic and turgor pressures) at the fruit level. Variation
in elastic fruit growth was modeled as a function of the elastic modulus and variation in turgor pressure. Variation in plastic
fruit growth was modeled using the Lockhart (1965) equation. In this model, plastic growth parameters (yield threshold pressure
and cell wall extensibility) varied during fruit growth. Outputs of the model were diurnal and seasonal fruit growth, and
fruit turgor pressure. These variables were simulated with good accuracy by the model, particularly the observed increase
in fruit size with increasing availability of assimilate supply. Shrinkage was sensitive to the surface conductance of fruit
peel, the elasticity modulus and the hydraulic conductivity of fruit, whereas fruit growth rate was highly sensitive to parameters
linked to changes in wall extensibility and yield threshold pressure, regardless of the assimilate supply. According to the
model, plastic growth was generally zero during the day and shrinkage and swelling were linked to the elastic behavior of
the fruit. During the night, plastic and elastic growths were positive, resulting in fruit expansion.
Keywords:
expansion, Mangifera indica, shrinkage, turgor pressure, water relations.
