Article Figures & Data
Figures
- Figure 1.
Changes in hydraulic parameters of whole berries, receptacles, and pedicels over the course of development (early preveraison = 20–40 DAA; late preveraison = 40–60 DAA; veraison/early postveraison = 60–80 DAA; late postveraison = 80–100 DAA). A, Measured Rh at each cut section (MPa s−1 m−3). B, Rh calculated for each component of the berry by subtraction, with Rberry = Rh (whole berry) – Rh (receptacle) and Rrecep = Rh (receptacle) – Rh (pedicel). Values are means with error bars showing se. For each parameter, different letters indicate significant differences (P < 0.05) between means (Tukey's honestly significant difference).
- Figure 2.
Perfusion of acid fuchsin into grape berries cut at the brush region at different stages of development. Images are shown for berries at 30 DAA with central and all peripheral vascular bundles conducting (A), at 75 DAA with central and all peripheral vascular bundles remaining conductive (B), and at 100 DAA with only a small number of bundles still conducting dye (C). [See online article for color version of this figure.]
- Figure 3.
Light micrographs showing transverse sections of pedicel tissue in grape berries stained with berberine-aniline blue. A, Preveraison pedicel (30 DAA), with inset showing a high-magnification view of xylem tissue. B, Postveraison pedicel (75 DAA) showing heavily lignified xylem (x), thinner walled ray cells (r), and fiber caps (f) positioned over phloem tissue (p). Bars = 100 μm or 50 μm for the inset. [See online article for color version of this figure.]
- Figure 4.
CryoSEM images showing pedicel and receptacle tissue for preveraison (31 DAA; A–C) and postveraison (93–100 DAA; D–F) grape berries. A, Transverse section through receptacle showing xylem (x), phloem (p), and ray (r). Conducting tracheary elements (arrows) appear dark in comparison with surrounding living cells because of low solute content in the ice. B, Transverse section showing closer detail of conducting elements (white arrows) surrounded by living cells in which organelles can be seen (black arrows). C, Transverse section showing lateral branching of a vascular bundle. Tracheary elements can be seen connected through bordered pits and annular secondary thickening (arrows). D, Transverse section through receptacle showing tracheary elements containing high amounts of solute relative to preveraison samples. E, Closer detail showing many tracheary elements containing white lacy patterning indicating high concentrations of solutes (arrows). F, Transverse section showing some postveraison tracheary elements that appear similar to preveraison samples with lower solute concentrations.
- Figure 5.
Aquaporin in grape berry flesh over the course of development. Isoforms are separated into the PIP1 (A) and PIP2 (B) gene families. Values are means with bars showing se across all biological and technical replicates.
- Figure 6.
The relationship between grape berry Rh and backflow from the fruit into the parent plant. Flow rates were calculated using Rh and xylem water potential gradients (ΔΨx) between the fruit and the stem xylem. Four scenarios of diurnal time course of ΔΨx are shown (A–D) in the inset, with diurnal time courses in stem water potential based on data for irrigated postveraison vines from Greenspan et al. (1996). The black circles show mean whole berry Rh measured at 80 to 100 DAA.
- Figure 7.
E-loop region amino acid sequence alignment of the grapevine PIPs (VvPIPs). Shaded residues in PIP1s represent those that Fetter et al. (2004) found to be critical for the heteromerization between maize (Zea mays) ZmPIP1-2 and ZmPIP2-5, leading to increases in membrane water permeability.
- Figure 8.
Experimental apparatus used to measure Rh of grape berries, receptacles, and pedicels. Pedicels were glued into Teflon tubing and connected to a water-filled microcapillary. A gas pressure of 0.1 MPa was applied to the capillary, and the rate of water movement into the berry was measured by tracking the movement of the meniscus over time. The positions of cuts made to measure receptacle and pedicel Rh are shown.
