Figure 2. Host effects on differential gene expression at the two sampling time points . The individual effect of the two host plants as well as the effect of their interaction in the number of differentially expressed genes (FDR < 0.05) was measured at both sampling time points (2 hrs and 17 hrs). The effect of the hosts differed between the experiments: In Switch A (top row) the highest number of significantly differentially expressed genes was associated with Host 1 (H1, blue) at both time points. In Switch B a stronger effect of Host 2 (H2, yellow) was measured 17 hours after the host switch. The interaction between the two hosts (H1xH2, grey) explained only a small or no proportion of the significantly differentially expressed genes. Percentages in parentheses represent the proportion of the total number of significantly differentially expressed genes at a given time point. The highest number of significantly differentially expressed genes at a time point is shown in bold.