eCite Digital Repository
Light-induced changes in hydrogen, calcium, potassium, and chloride ion fluxes and concentration from mesophyll and epidermal tissues of bean leaves. Understanding the ionic basis of light-induced bioelectrogenesis
Citation
Shabala, SN and Newman, IA, Light-induced changes in hydrogen, calcium, potassium, and chloride ion fluxes and concentration from mesophyll and epidermal tissues of bean leaves. Understanding the ionic basis of light-induced bioelectrogenesis, Plant Physiology, 119, (3) pp. 1115-1124. ISSN 0032-0889 (1999) [Refereed Article]
DOI: doi:10.1104/pp.119.3.1115
Abstract
Noninvasive, ion-selective vibrating microelectrodes were used to measure the kinetics of H+, Ca2+, K+, and Cl- fluxes and the changes in their concentrations caused by illumination near the mesophyll and attached epidermis of bean (Vicia faba L.). These flux measurements were related to light-induced changes in the plasma membrane potential. The influx of Ca2+ was the main depolarizing agent in electrical responses to light in the mesophyll. Changes in the net fluxes of H+, K+, and Cl- occurred only after a significant delay of about 2 min, whereas light-stimulated influx of Ca2+ began within the time resolution of our measurements (5 s). In the absence of H+ flux, light caused an initial quick rise of external pH near the mesophyll and epidermal tissues. In the mesophyll this fast alkalinization was followed by slower, oscillatory pH changes (5-15 min); in the epidermis the external pH increased steadily and reached a plateau 3 min later. We explain the initial alkalinization of the medium as a result of CO2 uptake by photosynthesizing tissue, whereas activation of the plasma membrane H+ pump occurred 1.5 to 2 min later. The epidermal layer seems to be a substantial barrier for ion fluxes but not for CO2 diffusion into the leaf.
Item Details
Item Type: | Refereed Article |
---|---|
Research Division: | Biological Sciences |
Research Group: | Plant biology |
Research Field: | Plant physiology |
Objective Division: | Expanding Knowledge |
Objective Group: | Expanding knowledge |
Objective Field: | Expanding knowledge in the environmental sciences |
UTAS Author: | Shabala, SN (Professor Sergey Shabala) |
UTAS Author: | Newman, IA (Dr Ian Newman) |
ID Code: | 17675 |
Year Published: | 1999 |
Web of Science® Times Cited: | 87 |
Deposited By: | Agricultural Science |
Deposited On: | 1999-08-01 |
Last Modified: | 2000-06-06 |
Downloads: | 0 |
Repository Staff Only: item control page