title: The positive effect of skin transpiration in peach fruit growth.
abstract: The effect of fruit transpiration on the mechanisms driving peach (Prunus persica (L.) Batsch) daily growth was investigated. In peach, fruit water losses increase during the season and might play a key role in determining fruit growth. Skin transpiration was reduced during the cell expansion stage by enclosing fruit in plastic bags fitted with holes. In the first year, diameter changes of bagged and control fruit were precisely monitored for 15 days, and percentage dry matter and soluble solids content were determined during the experiment and at harvest. In the second year, midday fruit water potential, daily patterns of fruit growth and of vascular and transpiration flows were monitored. Bagging reduced fruit daily growth on some days, and negatively affected both fruit dry matter percentage and soluble solids content. Fruit transpiration rate was reduced during the midday hours, thus increasing midday fruit water potential and lowering xylem inflows. In accordance with the Münch hypothesis on traslocation, these conditions likely decreased the necessary gradient needed for the transport of phloem sap to sink organs, as in the afternoon, bagged fruit showed lower phloem inflows. These data suggest that skin transpiration in peach has a positive effect on fruit growth, as it enhances fruit phloem import.
authors.affiliation: Dipartimento Colture Arboree, University of Bologna, V.le Fanin 46, 40127 Bologna, Italy. bmorandi@agrsci.unibo.it
authors.forename: Brunella
authors.initials: B
authors.lastname: Morandi
authors.forename: Luigi
authors.initials: L
authors.lastname: Manfrini
authors.forename: Pasquale
authors.initials: P
authors.lastname: Losciale
authors.forename: Marco
authors.initials: M
authors.lastname: Zibordi
authors.forename: Luca
authors.initials: L
authors.lastname: Corelli-Grappadelli
mesh_terms: D018533:Biomass; D002940:Circadian Rhythm / Q000502:physiology; D005638:Fruit / Q000254:growth & development*; D052585:Phloem / Q000502:physiology; D019441:Plant Epidermis / Q000502:physiology*; D018526:Plant Transpiration / Q000502:physiology*; D027861:Prunus / Q000254:growth & development*; D012212:Rheology; D012995:Solubility; D013696:Temperature; D014867:Water; D052584:Xylem / Q000502:physiology
chemical_list: D014867:Water