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• Higher leaf vein density (Dvein) enables higher rates of photosynthesis because enhanced water transport allows higher leaf conductances to CO2 and water. If the total cost of leaf venation rises in proportion to the density of minor veins, the most efficient investment in leaf xylem relative to photosynthetic gain should occur when the water transport capacity of the leaf (determined by Dvein) matches potential transpirational demand (determined by stomatal size and density). • We tested whether environmental plasticity in stomatal density (Dstomata) and Dvein were linked in the evergreen tree Nothofagus cunninghamii to achieve a balance between liquid and gas phase water conductances. Two sources of variation were examined; within-tree light acclimation, and differences in sun leaves among plants from ecologically diverse populations. • Strong, linear correlations between Dvein and Dstomata were found at all levels of comparison. The correlations between liquid- and vapour-phase conductances implied by these patterns of leaf anatomy were confirmed by direct measurement of leaf conductance in sun and shade foliage of an individual tree. • Our results provide strong evidence that the development of veins and stomata are coordinated so that photosynthetic yield is optimized relative to carbon investment in leaf venation.

Item Type:	Refereed Article
Research Division:	Biological Sciences
Research Group:	Evolutionary Biology
Research Field:	Biological Adaptation
Objective Division:	Environment
Objective Group:	Flora, Fauna and Biodiversity
Objective Field:	Forest and Woodlands Flora, Fauna and Biodiversity
Author:	Brodribb, TJ (Professor Tim Brodribb)
Author:	Jordan, GJ (Associate Professor Greg Jordan)
ID Code:	71956
Year Published:	2011
Web of Science® Times Cited:	64
Deposited By:	Plant Science
Deposited On:	2011-08-16
Last Modified:	2017-11-01
Downloads:	1 View Download Statistics