Figure 2. Aphid survival in relation to pre-exposure with bacterial elicitors and subsequent challenge with E. coli.

A) In Experiment 4, while E. coli reduced aphid survival (pathogen-infected treatments are dotted, uninfected treatments are solid), there was no significant interaction between challenge with live bacteria and pre-exposure to bacterial elicitors (pre-exposed treatments are red, unprimed treatments are black). As harboring facultative symbionts did not significantly alter survival, aphids with and without facultative symbionts are pooled. B) In follow-up Experiment 5, giving all aphids (line 5AR) a subsequent challenge with E. coli, pre-exposure with bacterial elicitors decreased survival. C) In follow-up Experiment 6, giving all aphids (genotype LSR1) a subsequent challenge with E. coli, pre-exposure did not impact survival.