Figure 2.

Hierarchical clustering heat map of differential volatile compounds produced by olive trees. Each column represents the samples obtained by plants treated with Trichoderma spores (M10, TH1, T22, KV906, and GV41,) or metabolites (6PP and HA). Water-treated plants served as controls (CTRL). In the heat map, red and blue colors indicate higher and lower chemical abundance, respectively. Treatments are indicated according to the color scale (class) shown in the legend at the top right. Data are presented as individual values from each biological replication. Statistical differences were determined using one-way ANOVA (p < 0.05).