Publication
Title
Variations in bulk leaf carbon isotope discrimination, growth and related leaf traits among three **Populus nigra** L. populations
Author
Abstract
Tests were carried out to determine whether variations in the hydraulic architecture of eight Populus deltoides×Populus nigra genotypes could be related to variations in leaf function and growth performance. Measurements were performed in a coppice plantation on 1-year-old shoots under optimal irrigation. Hydraulic architecture was characterized through estimates of hydraulic efficiency (the ratio of conducting sapwood area to leaf area, AX:AL; leaf- and xylem-specific hydraulic conductance of defoliated shoots, kSL and kSS, respectively; apparent whole-plant leaf-specific hydraulic conductance, kplant) and xylem safety (water potential inducing 50% loss in hydraulic conductance). The eight genotypes spanned a significant range of kSL from 2.63 kg s−1 m−2 MPa−1 to 4.18 kg s−1 m−2 MPa−1, variations being mostly driven by kSS rather than AX:AL. There was a strong trade-off between hydraulic efficiency and xylem safety. Values of kSL correlated positively with kplant, indicating that high-pressure flowmeter (HPFM) measurements of stem hydraulic efficiency accurately reflected whole-plant water transport efficiency of field-grown plants at maximum transpiration rate. No clear relationship could be found between hydraulic efficiency and either net CO2 assimilation rates, water-use efficiency estimates (intrinsic water-use efficiency and carbon isotope discrimination against 13C), or stomatal characteristics (stomatal density and stomatal pore area index). Estimates of hydraulic efficiency were negatively associated with relative growth rate. This unusual pattern, combined with the trade-off observed between hydraulic efficiency and xylem safety, provides the rationale for the positive link already reported between relative growth rate and xylem safety among the same eight P. deltoides×P. nigra genotypes.
Language
English
Source (journal)
Tree physiology. - Victoria
Publication
Victoria : 2011
ISSN
0829-318X
DOI
10.1093/TREEPHYS/TPR089
Volume/pages
31 :10 (2011) , p. 1076-1087
ISI
000295930200005
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 05.12.2011
Last edited 15.11.2022
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