Journal Article

The hydraulic conductance of <i>Fraxinus ornus</i> leaves is constrained by soil water availability and coordinated with gas exchange rates

Emmanuelle Gortan, Andrea Nardini, Antonio Gascó and Sebastiano Salleo

in Tree Physiology

Volume 29, issue 4, pages 529-539
Published in print April 2009 | ISSN: 0829-318X
Published online April 2009 | e-ISSN: 1758-4469 | DOI: http://dx.doi.org/10.1093/treephys/tpn053
The hydraulic conductance of Fraxinus ornus leaves is constrained by soil water availability and coordinated with gas exchange rates

More Like This

Show all results sharing this subject:

  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Leaf hydraulic conductance (K leaf) is known to be an important determinant of plant gas exchange and photosynthesis. Little is known about the long-term impact of different environmental factors on the hydraulic construction of leaves and its eventual consequences on leaf gas exchange. In this study, we investigate the impact of soil water availability on K leaf of Fraxinus ornus L. as well as the influence of K leaf on gas exchange rates and plant water status. With this aim, K leaf, leaf conductance to water vapour (g L), leaf water potential (Ψleaf) and leaf mass per area (LMA) were measured in F. ornus trees, growing in 21 different sites with contrasting water availability. Plants growing in arid sites had lower K leaf, g L and Ψleaf than those growing in sites with higher water availability. On the contrary, LMA was similar in the two groups. The K leaf values recorded in sites with two different levels of soil water availability were constantly different from each other regardless of the amount of precipitation recorded over 20 days before measurements. Moreover, K leaf was correlated with g L values. Our data suggest that down-regulation of K leaf is a component of adaptation of plants to drought-prone habitats. Low K leaf implies reduced gas exchange which may, in turn, influence the climatic conditions on a local/regional scale. It is concluded that leaf hydraulics and its changes in response to resource availability should receive greater attention in studies aimed at modelling biosphere–atmosphere interactions.

Keywords: leaf; leaf water potential; water stress

Journal Article.  6719 words.  Illustrated.

Subjects: Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.