The bulk elastic modulus and the reversible properties of cell walls in developing Quercus leaves

• Published in: Plant and cell physiology Vol. 47; no. 6; pp. 715 - 725
• Main Authors: Saito, T.(Osaka Univ., Suita (Japan)), Soga, K, Hoson, T, Terashima, I
• Format: Journal Article
• Language: English
• Published: Japan Oxford University Press 01-06-2006; Oxford Publishing Limited (England)
• Subjects: Acw; Aleaf; Apal; Astrip; Biomechanical Phenomena; Bulk elastic modulus; bulk elastic modulus and that calculated from Young’s modulus; Cell Size; cell volume; Cell Wall - physiology; Cell Wall - ultrastructure; cell wall thickness; CELL WALLS; cross-sectional area in a leaf transverse section including all cell types and intercellular air spaces; cross-sectional area of a leaf strip for the stretch test; cross-sectional area of the cell walls; DP and DT; elastic; FEUILLE; FLE; free water content and that at turgor loss point; FWC and FWCtlp; HOJAS; Instron technique; l and l0; Lcw; leaf area; leaf fresh weight at water saturation; leaf mass per area; leaf tissues and palisade cells; leaf water potential at turgor loss point and osmotic potential of leaves fully saturated with water; LEAVES; length of a leaf strip for the stretch test and that before the test; LMA and DW/LA; MECHANICAL PROPERTIES; Models, Theoretical; molar concentration of solutes in the leaf cells at water saturation; Npal; number of cells in the first layer of palisade tissue in a leaf paradermal section; PARED CELULAR; PAROI CELLULAIRE; perimeter length at the center of cell walls; Plant Leaves - chemistry; Plant Leaves - cytology; Plant Leaves - growth & development; Plant Leaves - physiology; Plant Physiological Phenomena; Plant Transpiration - physiology; plastic and total compliance; Poison’s ratio; Pressure–volume (P–V) curve; pressure–volume curve; PROPIEDADES MECANICAS; PROPRIETE MECANIQUE; P–V curve; Quercus - cytology; Quercus - growth & development; Quercus - physiology; QUERCUS GLAUCA; QUERCUS SERRATA; radius of a spherical shell; relative water content and that at turgor loss point; Reversible properties of cell walls; RWC and RWCtlp; sat; stress in the walls; Stress–strain curve; Tcw and t; the date of full leaf area expansion; the ratio of symplasmic water content to total water content in a leaf; tlp and Ψπ; transverse area of a cell in the first layer of palisade tissue in a leaf paradermal section; turgor pressure; V0/Vt; Vcell; Vleaf and Vpal; volume of cells; Water - analysis; width of a leaf transverse section; Young’s modulus; ε and εstretch; Ψp and P
• ISSN: 0032-0781; 1471-9053
• DOI: 10.1093/pcp/pcj042

We examined the relationship between the bulk elastic modulus (epsilon) of an individual leaf obtained by the pressure-volume (P-V) technique and the mechanical properties of cell walls in the leaf. The plants used were Quercus glauca and Q. serrata, an evergreen and a deciduous broad-leaved tree species, respectively. We compared epsilon and Young's modulus of leaf specimens determined by the stretch technique at various stages of their leaf development. The results showed that epsilon increased from approximately 5 to 20 MPa during leaf development, although other potential determinants of epsilon such as the apoplastic water content in the leaf and the diameter of a palisade tissue cells remained almost constant. epsilon in these two species was similar at every developmental stages, although the apparent mechanical strength of the leaf lamina and thickness of mesophyll cell walls were greater in Q. glauca. There were significant linear relationships between Young's modulus and epsilon (P 0.01; Rsup(2)