Mapping 'hydroscapes' along the iso- to anisohydric continuum of stomatal regulation of plant water status.
The concept of iso- vs. anisohydry has been used to describe the stringency of stomatal regulation of plant water potential (ψ). However, metrics that accurately and consistently quantify species' operating ranges along a continuum of iso- to anisohydry have been elusive. Additionally, most approaches to quantifying iso/anisohydry require labour-intensive measurements during prolonged drought. We evaluated new and previously developed metrics of stringency of stomatal regulation of ψ during soil drying in eight woody species and determined whether easily-determined leaf pressure-volume traits could serve as proxies for their degree of iso- vs. anisohydry. Two metrics of stringency of stomatal control of ψ, (1) a 'hydroscape' incorporating the landscape of ψ over which stomata control ψ, and (2) the slope of the daily range of ψ as pre-dawn ψ declined, were strongly correlated with each other and with the leaf osmotic potential at full and zero turgor derived from pressure-volume curves.
USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, 97331, USA. Rick.Meinzer@oregonstate.edu, fmeinzer@fs.fed.us.
Frederick C
FC
Meinzer
USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, 97331, USA.
David R
DR
Woodruff
Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA.
Danielle E
DE
Marias
Department of Botany, University of Wisconsin-Madison, Madison, WI, 53705, USA.
Duncan D
DD
Smith
Department of Botany, University of Wisconsin-Madison, Madison, WI, 53705, USA.
Katherine A
KA
McCulloh
Department of Biology, Western Oregon University, Monmouth, OR, 97361, USA.
Ava R
AR
Howard
Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA.
Alicia L
AL
Magedman
D004780:Environment, Controlled; D019684:Magnoliopsida / Q000502:physiology*; D054046:Plant Stomata / Q000502:physiology*; D018526:Plant Transpiration / Q000502:physiology*; D014867:Water / Q000378:metabolism*
D014867:Water
Anisohydry; drought resistance; isohydry; leaf osmotic potential; leaf turgor; plant traits; plant water potential; stomata