Electric conductivity (EC_1:5, dS m^-1) of substrate samples after 6-week treatments with the indicated NaCl concentrations, for the seven <i>P</i>. <i>abies</i> populations under study.

<p>Means with SD (n = 3). For each population, different lowercase letters above the bars indicate significant differences among treatments and different capital letters indicate significant differences among populations undergoing the same treatment, according to the Tukey test (α = 0.05).