Stiffness gradients in vascular bundles of the palmWashingtonia robusta
- 1 July 2008
- journal article
- Published by The Royal Society in Proceedings. Biological sciences
- Vol. 275 (1648), 2221-2229
- https://doi.org/10.1098/rspb.2008.0531
Abstract
Palms can grow at sites exposed to high winds experiencing large dynamic wind and gust loads. Their stems represent a system of stiff fibrous elements embedded in the soft parenchymatous tissue. The proper design of the interface of the stiffening elements and the parenchyma is crucial for the functioning of the stem. The strategy of the palm to compromise between stiff fibre caps and the soft parenchymatous tissue may serve as a model system for avoiding stress discontinuities in inhomogeneous and anisotropic fibre-reinforced composite materials. We investigated the mechanical, structural and biochemical properties of the fibre caps of the palm Washingtonia robusta at different levels of hierarchy with high spatial resolution. A gradual decrease in stiffness across the fibre cap towards the surrounding parenchymatous tissue was observed. Structural adaptations at the tissue level were found in terms of changes in cell cross sections and cell wall thickness. At the cell wall level, gradients across the fibre cap were found in the degree of orientation of the microfibrils and in the lignin level and composition. The impact of these structural variations in the local material stiffness distribution is discussed.This publication has 30 references indexed in Scilit:
- Exploring the micromechanical design of plant cell wallsAmerican Journal of Botany, 2006
- On the role of interface polymers for the mechanics of natural polymeric compositesPhysical Chemistry Chemical Physics, 2004
- Cellulose and collagen: from fibres to tissuesCurrent Opinion in Colloid & Interface Science, 2003
- Experimental evidence for a mechanical function of the cellulose microfibril angle in wood cell wallsPhilosophical Magazine A, 1999
- Dependency of the Tensile Modulus on Transverse Dimensions, Water Potential, and Cell Number of Pith ParenchymaAmerican Journal of Botany, 1988
- Developmental Anatomy of the Stem of Welfia georgii, Iriartea gigantea, and Other Arborescent Palms: Implications for Mechanical SupportAmerican Journal of Botany, 1987
- Mechanical Structure of the Stem of Arborescent PalmsBotanical Gazette, 1987
- Growth patterns in the stem of the palm Archontophoenix cunninghamianaBotanical Journal of the Linnean Society, 1978
- The Location of Guaiacyl and Syringyl Lignins in Birch Xylem TissueHolzforschung, 1970
- The Ultraviolet Absorption Spectra of Simple Unsaturated Compounds. I. Mono- and p-Disubstituted Benzene DerivativesJournal of the American Chemical Society, 1947