We investigated the role of xylem cavitation, plant hydraulic conductance, and root pressure in the response of rice (Oryza sativa) gas exchange to water stress. In the field (Philippines), the percentage loss of xylem conductivity (PLC) from cavitation exceeded 60% in leaves even in watered controls. The PLC versus leaf water potential relationship indicated diurnal refilling of cavitated xyle...

Leaf hydraulic conductance (k leaf) is a central element in the regulation of leaf water balance but the properties of k leaf remain uncertain. Here, the evidence for the following two models for k leaf in well-hydrated plants is evaluated: (i) k leaf is constant or (ii) k leaf increases as transpiration rate (E) increases. The difference between stem and leaf water potential (ΔΨstem-leaf), sto...

Experimental evidence indicates that the stomatal conductance and nitrogen concentration ([N]) of foliage decline under CO2 enrichment, and that the percentage growth response to elevated CO2 is amplified under water limitation, but reduced under nitrogen limitation. We advance simple explanations for these responses based on an optimisation hypothesis applied to a simple model of the annual ca...

 Net photosynthesis rate (Pn), stomatal conductance (gs) and transpiration rate (E) of anise hyssop were measured during the four cloudless days, in reference to diurnal fluctuations of leaf temperature (Tleaf), leaf vapor pressure deficit (VPD leaf) and photosynthetic photon flux density (PPFD) in well watered (WW), stressed (S) and recovered (R) plants. An analysis of measured data showed tha...

While the fundamental trade-off in leaf traits related to carbon capture as described by the leaf economics spectrum is well-established among plant species, the relationship of the leaf economics spectrum to stem hydraulics is much less known. Since carbon capture and transpiration are coupled, a close connection between leaf traits and stem hydraulics should be expected. We thus asked whether...

evaluating of some physiological indices for recognizing water deficit effects, selecting water deficit tolerant oilseed rape genotypes and also evaluation of drought effects on seed and oil yields and its components were the goals of this study. the experiment was conducted as factorial based on a randomized complete blocks design with three replications in east azarbaijan research center for ...

A four- to seven-fold enhancement of leaf hydraulic conductance by light has been reported in three temperate tree species. The enhancement occurs in the liquid-flow pathway between the petiole and the site of water evaporation. The enhancement occurs within 1 h, and dissipates in darkness over a period of 1 to 10 h depending on species. Here we report light-induced enhancement of leaf hydrauli...

Whole-plant hydraulic conductance, shoot growth, and leaf photosynthetic properties were measured on kiwifruit vines with four clonal rootstocks to examine the relationship between plant hydraulic conductance and leaf stomatal conductance (gs) and to test the hypothesis that reduced hydraulic conductance can provide an explanation for reductions in plant vigour caused by rootstocks. The rootsto...

Photosynthetic efficiency is a critical determinant of crop yield potential, although it remains below the theoretical optimum in modern crop varieties. Enhancing mesophyll conductance (i.e. the rate of carbon dioxide diffusion from substomatal cavities to the sites of carboxylation) may increase photosynthetic and water use efficiencies. To improve water use efficiency, mesophyll conductance s...