FIG 5.

Box-and-whiskers representation of protease activities of the Suillus strains growing in BSA medium (expressed as fluorescence units) with different glucose concentrations (0, 1, 2.5, and 5 g liter⁻¹). Three species were investigated: S. luteus (strains P1, P3, P4, P8, and P13), S. bovinus (strains P1, P2, P4, P10, Z1, Z2, Z3, and Z4), and S. variegatus (strains Z1, ZJW3, ZJW4, ZW6, and ZJW13). For S. bovinus, strains from both Zolder and Paal sites were investigated. Different letters indicate significant differences among treatment soil type means as determined by post hoc Tukey HSD tests. The boxes represent the 2nd and 3rd interquartile ranges; the horizontal lines in the boxes represent the median; the upper and lower bars outside the boxes represent the 1st (Q1) and 4th quartiles, respectively; and the dots outside the bars represent the outliers (defined as values outside 1.5 times the interquartile range below Q1 and above Q3).