Fig. 4.

Effect of damage by three herbivore species on the trypsin protease inhibitor activity in the damaged and adjacent undamaged leaves of young Populus nigra trees as compared to equivalent leaves from non-infested control trees. Samples were collected 44 hr after infestation with caterpillars of the two lepidopteran species Amata mogadorensis and Lymantria dispar, adults of the coleopteran species Phratora vulgatissima, and untreated control plants. The boxplots represent the median ± 1.5 x interquartile range of n = 10 tree replicates. Pairwise comparisons were conducted using Dunn’s post hoc test (Kruskal-Wallis) and are indicated by small letters. Circles indicate outliers and asterisks indicate extreme outliers. The results of statistical analyses comparing only the herbivore treatments are given in Table 1