Leaf hydraulic conductance varies with vein anatomy across Arabidopsis thaliana wild‐type and leaf vein mutants

• Published in: Plant, cell and environment Vol. 38; no. 12; pp. 2735 - 2746
• Main Authors: Caringella, Marissa A, Bongers, Franca J, Sack, Lawren
• Format: Journal Article
• Language: English
• Published: United States Blackwell Scientific Publications 01.12.2015; Wiley Subscription Services, Inc
• Subjects: Arabidopsis - anatomy & histology; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; bundle sheath; bundle sheath cells; cotyledons; Genotype; leaf anatomy; leaf hydraulics; leaves; mesophyll; mutants; Mutation; paleobotany; Phenotype; Plant Leaves - anatomy & histology; Plant Leaves - genetics; Plant Leaves - physiology; Plant Transpiration - physiology; Plant Vascular Bundle - anatomy & histology; Plant Vascular Bundle - genetics; Plant Vascular Bundle - physiology; vein density; VLA; xylem; Xylem - anatomy & histology; Xylem - genetics; Xylem - physiology; leaf anatomy; bundle sheath; VLA; leaf hydraulics; vein density
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.12584

Leaf venation is diverse across plant species and has practical applications from paleobotany to modern agriculture. However, the impact of vein traits on plant performance has not yet been tested in a model system such as Arabidopsis thaliana. Previous studies analysed cotyledons of A. thaliana vein mutants and identified visible differences in their vein systems from the wild type (WT). We measured leaf hydraulic conductance (Kₗₑₐf), vein traits, and xylem and mesophyll anatomy for A. thaliana WT (Col‐0) and four vein mutants (dot3‐111 and dot3‐134, and cvp1‐3 and cvp2‐1). Mutant true leaves did not possess the qualitative venation anomalies previously shown in the cotyledons, but varied quantitatively in vein traits and leaf anatomy across genotypes. The WT had significantly higher mean Kₗₑₐf. Across all genotypes, there was a strong correlation of Kₗₑₐf with traits related to hydraulic conductance across the bundle sheath, as influenced by the number and radial diameter of bundle sheath cells and vein length per area. These findings support the hypothesis that vein traits influence Kₗₑₐf, indicating the usefulness of this mutant system for testing theory that was primarily established comparatively across species, and supports a strong role for the bundle sheath in influencing Kₗₑₐf.