ACCUMULATION OF SODIUM AND CHLORIDE IN DIFFERENT TISSUES OF NAVY AND TEPARY BEANS

Abstract

Navy (Phaseolus vulgaris L.) and tepary (P. acutifolius Gray) beans were grown hydroponically in a growth chamber with no NaCl or -0.25 MPa NaCl for 9 days beginning 22 days after planting. Chloride and sodium distribution in leaves and roots as well as percent ion leakage as an indication of membrane integrity in leaves were determined. Chloride and sodium levels in NaCl treated plants were significantly higher than in controls. Chloride distribution was not significantly different between plant parts or between plant species. Sodium distribution was significantly different between roots of the two species, but not between leaves of the two species. The navy root tissues contained twice as much sodium as the leaves, whereas, in tepary sodium levels were similar in roots and leaves. Percent ion leakage showed no notable trends relative to plant species or to NaCl treatments, but a significant difference was observed between younger and older leaves on the same plant.