Effects of winter pruning and of water restriction on fruit and vegetative growth, water potential and leaf gas exchange during the final stage of rapid growth in an early maturing peach cultivar
Résumé
Three intensities of winter pruning and of water restriction were assessed in a three-year-old early maturing peach cultivar under orchard and pot training, respectively. Under increasing intensities of pruning, peach growth was not limited at fruit maturity, whereas peach growth was limited under increasing water restriction. Severe pruning and high water restriction contributed to reducing the total shoot length compared to the control trees. Stem water potential decreased under severe pruning and high water restriction, whereas leaf stomatal conductance and transpiration rate were enhanced under severe pruning and limited under high water restriction. Leaf temperature and sub-stomatal CO2 concentration did not vary under different pruning intensities, whereas they increased and decreased, respectively, under increasing water restrictin. Under the different pruning intensities, leaf stomatal conductance and transpiration rate were correlated to the shoot length per unit fruit-bearing shoot length, suggesting that vegetative growth could be an alternate sink to the one induced by fruit growth.