An opposite trend between xylem sap Na+and K+concentration was observed with increasing NaCl concentration in the growth medium, where K+decreased in both genotypes (Fig. 5).Subsequently xylem sap K+/Na+was significantly decreased athigher levels of growth medium NaCl compared to control. Highly significant differences between salt-tolerant (Indent-1) and salt-sensitive (Red Ball) genotypes were observed at saline levels (75and 150 mM) in xylem sap Na+and K+concentrations. Potassium application had a significant positive effect on xylem sap K+and K+/Na+concentration and negative effect on Na+concentration across all NaCl levels.