The Influence of Pesticide Exposure on Route-specific Infection Outcomes
While oral infection with Btt did not result in immediate excess mortality compared to unexposed individuals, we considered the possibility that infection outcomes could be exposure route-specific. To determine whether the interaction between pesticide resistance, exposure to pesticides, and infection outcomes might be route-dependent, we septically infected susceptible and OP-selection regime larvae exposed to control and OP diets. Individuals from the susceptible regime that were exposed to OP had lower survival against septic Bttinfection compared to the other groups (Fig. 2; Suppl. Table 6) indicating an outsized cost of combined OP exposure and septicBtt infection in control regime larvae. This result contrasts with the improved survival observed in the Bt x OP treatment interaction term after oral exposure in that after septic infection, beetles co-exposed to OP did not have higher survival (Fig. 1A, OP PTx:BtTx).