The photocontrol of the functional coupling between photosynthesis and stomatal conductance in the leaf was investigated in gas exchange experiments using monochromatic light provided by lasers. Net photosynthesis and stomatal conductance were measured in attached leaves of Malva parviflora L. as a function of photon irradiance at 457.9 and 640.0 nanometers.Photosynthetic rates and quantum yiel...

Collatz, G.J., Ball, J.T., Grivet, C. and Berry, J.A., 1991. Physiological and environmental regulation of stomatal conductance, photosynthesis and transpiration: a model that includes a laminar boundary layer. Agric. For. Meteorol,, 54: 107-136. This paper presents a system of models for the simulation of gas and energy exchange of a leaf of a C3 plant in free air. The physiological processes ...

The photosynthesis source-sink relationship in young Pinus canariensis seedlings was modified by stem girdling to investigate sprouting and cambial activity, feedback inhibition of photosynthesis, and stem and root hydraulic capacity. Removal of bark tissue showed a trade-off between sprouting and diameter growth. Above the girdle, growth was accelerated but the number of sprouts was almost neg...

Leaf hydraulics, gas exchange and carbon storage in Pinus edulis and Juniperus monosperma, two tree species on opposite ends of the isohydry-anisohydry spectrum, were analyzed to examine relationships between hydraulic function and carbohydrate dynamics. Leaf hydraulic vulnerability, leaf water potential (Ψl ), leaf hydraulic conductance (Kleaf ), photosynthesis (A), stomatal conductance (gs) a...

Methyl jasmonate and Epi-brassinolide as plant growth regulators have significant biological effects on plant growth, including increased tolerance to salt stress in plants. In this study, the effects of salinity stress and its interaction with methyl jasmonate and Epi-brassinolide on chlorophyll concentration, rate of photosynthesis, transpiration, stomatal conductance and resistance and chlor...

BACKGROUND AND AIMS The influence of stomatal architecture on stomatal conductance and on the developing concentration gradient was explored quantitatively by comparing diffusion rates of water vapour and CO(2) occurring in a set of three-dimensional stoma models. The influence on diffusion of an internal cuticle, a sunken stoma, a partially closed stoma and of substomatal chambers of two diffe...

Drought is a major constraint to crop production worldwide and landraces are one of the important genetic resources to crop improvement in the dry areas. The objective of this study was to investigate transpiration and yield responses of bambara groundnut (Vigna subterranea L. Verdc.) landraces exposed to a intermittent drought spell at an early reproductive stage. The four landraces (S19-3, Un...

The internal conductance to CO2 supply from substomatal cavities to sites of carboxylation poses a large limitation to photosynthesis. It is known that internal conductance is decreased by soil water deficits, but it is not known if it is affected by atmospheric water deficits (i.e. leaf to air vapour pressure deficit, VPD). The aim of this paper was to examine the responses of internal conduct...

Several studies have highlighted the negative effects of ozone (O3) on wheat development and productivity. The O3 are mediated by changes in photosynthetic carbon nitrogen metabolism, which difficult time-consuming to assess thus only measured sporadically throughout plant cycle. Stable isotope measurements grains can help integrate chronic exposure over lifespan plant. This particular study fo...

A new imaging system capable of simultaneously measuring stomatal conductance and fluorescence parameters, non-photochemical quenching (NPQ) and photochemical yield of photosystem II (Phi(PSII)), in intact leaves under aerobic conditions by both thermal imaging and chlorophyll fluorescence imaging was developed. Changes in distributions of stomatal conductance and fluorescence parameters across...