
Xylem flows into most fruits decline as the fruit develop, with important effects on mineral and carbohydrate accumulation. Mazzeo et al. use pressure chamber and flow-meter techniques to examine changes in xylem hydraulic resistance (RT) in kiwifruit, Actinidia deliciosa, during fruit development. They find that increased RT in the receptacle zone coincides with slowing of fresh-weight growth, reduced transpiration and rapid starch accumulation by the fruit. Shading of fruit also increases RT. They conclude that developmental changes in RT may be connected to changes in phloem functioning and the maintenance of water potential gradients between the stem and the fruit.