Influence of Boron on the Membrane Potential in Elodea densa and Helianthus annuus Roots and H Extrusion of Suspension Cultured Daucus carota Cells.
When following the membrane potential of Elodea densa leaf cells during a dark-light regime and analysing the different phases of the cycle, the pattern under boron deficiency resembled the one reported to occur after 3-(3,4-dichlorophenyl)-1,1-dimethylurea application. The potential in the dark slowly decreased when transferring Elodea densa leaflets and Helianthus annuus roots to a B-free medium and increased in the same way after B was added again. Addition of vanadate to inhibit plasmalemma ATPases in part mimicked the effects of B deficiency. It is suggested that B directly or indirectly affects the formation of a proton gradient. The effect of B on proton secretion was observed in various experiments with Daucus carota cell cultures. The results are discussed with respect to the possible involvement of B in membrane function and transport processes.
Blaser-Grill
J
J
Technische Universität München-Weihenstephan, Lehrstuhl für Pflanzenernährung, Weihenstephan, D-8050 Freising 12, Federal Republic of Germany.
Knoppik
D
D
Amberger
A
A
Goldbach
H
H