Allometry of cells and tissues within leaves
Grace P John1, Christine Scoffoni, Lawren Sack
1Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, California 90095-1606, USA.
American Journal of Botany
|September 28, 2013
Summary
This study reveals novel allometric relationships in leaf anatomy, showing how cell and tissue dimensions scale predictably with leaf thickness. These findings suggest fundamental design rules governing leaf construction across diverse species.
Area of Science:
- Plant Anatomy
- Allometry
- Leaf Morphology
Background:
- Allometric relationships in leaf dimensions are crucial for understanding leaf construction and function.
- Previous research has largely overlooked these relationships at the cellular and tissue levels.
Purpose of the Study:
- To investigate allometric relationships among leaf cell, cell wall, and tissue dimensions, and their correlation with whole-leaf thickness and area.
- To test hypothesized geometric scaling principles in leaf anatomical traits.
Main Methods:
- Analysis of leaf transverse cross-sections from 14 diverse angiosperm species using light microscopy.
- Measurement of leaf dimensions, tissue thicknesses, mesophyll and xylem cell sizes, and cell wall thicknesses.
Main Results:
- Discovery of strong allometries linking cell, cell wall, and tissue dimensions with gross leaf form.
- Isometric scaling of cell sizes and cell wall thicknesses within mesophyll tissues, but not in leaf vein xylem.
- Leaf thickness scales with cellular and tissue dimensions, while leaf area shows independence from anatomical traits.
Conclusions:
- The identified allometries indicate underlying design rules at the micro-scale of leaf construction.
- These relationships offer a basis for characterizing species-specific differences in leaf form and function.
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