The responses of steady state CO(2) assimilation rate (A), transpiration rate (E), and stomatal conductance (g(s)) to changes in leaf-to-air vapor pressure difference (DeltaW) were examined on different dates in shoots from Abies alba trees growing outside. In Ecouves, a provenance representative of wet oceanic conditions in Northern France, both A and g(s) decreased when DeltaW was increased f...

Mesophyll conductance (gm) has been shown to impose significant limitations to net CO2 assimilation (A) in various species during water stress. Net CO2 assimilation is also limited by stomatal conductance to water (gsw), both having been shown to co-vary with leaf hydraulic conductance (Kleaf). Lately, several studies have suggested a close functional link between Kleaf, gsw, and gm. However, s...

Leaf hydraulic and mesophyll CO2 conductance are both influenced by leaf anatomical traits, however it is poorly understood how the temperature response of these conductances differs between C4 C3 species with distinct anatomy. This study investigated (Kleaf), stomatal (gs) (gm) to CO2, traits in phylogenetically related Panicum antidotale (C4) P. bisulcatum (C3) grasses. The had lower outside ...

A growth regulator (G; 4-ethyl-1-hydroxy-4,8,8,10,10 pentamethyl-7,9-dioxo-2,3 dioxyabicyclo (4.4.0) decene-5) from Eucalyptus grandis (Maiden) reduced stomatal conductance and also photosynthetic capacity when fed through the transpiration stream of detached leaves. The concentration of G required for this effect was high (10(-4) molar), but the amount of G taken up (dose) was below the level ...

The structure of leaf vasculature viewed over a broad phylogenetic scale from lycophytes to eudicots correlates with stomatal conductance, providing the basis for the hypothesis that increasing vein density drove the evolution of high fluxes in angiosperms. Yet, the relationship between vascular geometry and gas fluxes breaks down at finer phylogenetic scales. In this Update, we derive a simple...

Living organisms are capable of discriminating thermal stimuli from noxious cold to noxious heat. For more than 30 years, it has been known that plant cells respond to cold with a large and transient depolarization. Recently, using transgenic Arabidopsis (Arabidopsis thaliana) expressing the calcium-sensitive protein aequorin, an increase in cytosolic calcium following cold treatment was observ...