Influence of <i>Hamiltonella defensa</i> infection and predator type on anti?predator behaviours in pea ( <i>Acyrthosiphon pisum</i> ) and potato aphids ( <i>Macrosiphum euphorbiae</i> )

Facultative endosymbionts can induce benefits and costs to their aphid hosts. In the pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), infection with ?-proteobacterium Hamiltonella defensa Moran et al. confer resistance against parasitoids, but may also reduce frequency of aggressive escape behaviours exhibited in response predators. potato aphids, Macrosiphum euphorbiae (Thomas) H. does not appear influence susceptibility parasitism, its impact on anti-predator remains unexplored. Here we investigated defensive two lines (differing defensa-infection status) four (that additionally differed genotype-associated parasitism susceptibility) when faced foraging ladybirds – Adalia bipunctata (L.) (Coleoptera: Coccinellidae) lacewings Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). ladybirds, symbiont-infected aphids proportionately fewer evasive defences (dropping walking away) than non-infected (cured) more frequent kicking. Ladybirds provoked evasive, aggressive, total lacewings. For symbiont status, predator type, genotype (i.e., assumed all influenced behavioural repertoires. Overall, infected showed greater differentiation predators uninfected lines. The presence be a key determinant behaviours, fitness consequences this are unresolved. our study, neither status nor affected number consumed by