Percentages of responding (A) <i>Aphidius matricariae</i> females that landed on each presented plant at the end of the 20-min dual-choice bioassay (grey bars).

<p>Different combinations of aphid-infested (dark grey bars) or non-infested (light grey bars) <i>Vicia faba</i> and <i>Camelina sativa</i> plantlets were presented to female wasps. The percentage of non-responding (B) parasitoids is presented on the right of the chart (white bars). Asterisks indicate significant differences (* <i>P</i> < 0.05; ** <i>P</i> < 0.01) in the choice made by responding parasitoids (Chi-square test). Same letters indicate non-significant differences (Kruskal-Wallis test, <i>P</i> > 0.05) between the percentages of non-responding parasitoids.