You are here: Home
/ Publication Information
Title: Does homeostasis or disturbance of homeostasis in minimum leaf water potential explain the isohydric versus anisohydric behavior of Vitis vinifera L. cultivars?
Author: Domec, Jean-Christophe; Johnson, Daniel M.;
Source: Tree Physiology 32:245–248
Publication Series: Scientific Journal (JRNL)
Description: Due to the diurnal and seasonal fluctuations in leaf-to-air vapor pressure deficit (D), one of the key regulatory roles played by stomata is to limit transpiration-induced leaf water deficit. Different types of plants are known to vary in the sensitivity of stomatal conductance (gs) to D with important consequences for their survival and growth. Plants that minimize any increase in transpiration with increasing D have a tight stomatal regulation of a constant minimum leaf water potential (Ψleaf); these plants are termed as ‘isohydric’ (Stocker 1956). Plants that have less control of Ψleafhave been termed as ‘anisohydric’ (Tardieu and Simonneau 1998). Isohydric plants maintain a constant Ψleaf by reducing gs and transpiration under drought stress. Therefore, as drought pushes soil water potential (Ψsoil) below this Ψleaf set point, the plant can no longer extract water for gas exchange. Anisohydric plants allow Ψleaf to decrease with rising D, reaching a much lower Ψleaf in droughted plants relative to well-watered plants (Tardieu and Simonneau 1998), so this strategy produces a gradient between Ψsoil and Ψleaf that allows gas exchange to continue over a greater decline in Ψsoil. Thus, anisohydric plants sustain longer periods of transpiration and photosynthesis, even under large soil water deficit, and are thought to be more drought tolerant than isohydric species (McDowell 2011).
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
Domec, Jean-Christophe; Johnson, Daniel M. 2012. Does homeostasis or disturbance of homeostasis in minimum leaf water potential explain the isohydric versus anisohydric behavior of Vitis vinifera L. cultivars? Tree Physiology 32:245–248.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility