Photosynthesis is often limited by the rate of CO(2) diffusion from the atmosphere to the chloroplast. The primary resistances for CO(2) diffusion are thought to be at the stomata and at photosynthesizing cells via a combination resulting from resistances of aqueous solution as well as the plasma membrane and both outer and inner chloroplast membranes. In contrast with stomatal resistance, the ...

Abstract Purpose Although the coordination between stomatal closure and aboveground hydraulics has extensively been studied, our understanding of impact belowground on regulation remains incomplete. Here, we investigated whether how water use maize ( Zea mays L.) varied under hydraulically contrasting soil textures. Our hypothesis is that a textural-specific drop in hydraulic conductivity assoc...

Water-soluble glycopeptides isolated from cultures of Ceratocystis ulmi have been reported to be toxins involved in Dutch elm disease. The influence of the glycopeptides on the water relations of Ulmus americana seedlings was tested by placing cut stems in glycopeptide preparations. After 4 hours in 200 micrograms per milliliter toxin the stem conductance of the seedlings was reduced by 79% and...

Water use efficiency (WUE) is considered as a determinant of yield under stress and a component of crop drought resistance. Stomatal behavior regulates both transpiration rate and net assimilation and has been suggested to be crucial for improving crop WUE. In this work, a dynamic model was used to examine the impact of dynamic properties of stomata on WUE. The model includes sub-models of stom...

The Amazon is undergoing environmental changes that can cause morphological and physiological in plants. general objective of this study was to evaluate the anatomical eco-physiological features Vouacapoua americana during development Brazilian Amazon. It observed stomata only occur abaxial face. Secretory structures are present throughout leaf blade. In central vein petiole region it xylem occ...

Concurrent measurements of evaporation, leaf conductance, irradiance, leaf water potential, and osmotic potential of maize (Zea mays L. cv. Pa602A) in soil at either high or low soil water potential were compared at several hours on two consecutive days in July. Hourly evaporation, measured on two weighing lysimeters, was similar until 1000 hours Eastern Standard Time, but thereafter evaporatio...