Sodium does not compete with calcium in saturating plasma membrane sites regulating na influx in salinized maize
1Plant Physiology Laboratory, Faculty of Agricultural Engineering, Technion IIT, Haifa 32000, Israel.
Plant Physiology
|May 1, 1991
Abstract:
Half maximal inhibition of sodium ((22)Na(+)) influx into maize (Zea mays L.) root segments incubated in solutions containing from 0.25 to 100 millimolar NaCl was consistently attained with external calcium activity at 0.26 +/- 0.10 millimolar. Sodium ions do not appear to compete with calcium during initial binding to sites on the plasma membrane that participate in the regulation of sodium influx under saline conditions.
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