Depression of a Coccinellid Functional Response to an Aphid by Sequestered Plant Chemical Defenses

Abstract

Blaauw investigated whether A. nerii feeding from constantly high aphid densities on Asclepias curassavica milkweed with high concentrations of cardenolides are better defended against coccinellid predator foraging than a cardenolide-free aphid, the green peach aphid - Myzus persicase. The functional response of the coccidenllid predator Harmonia axyridis as it interacted with the two different aphid species was observed. The null hypothesis was that there will be no difference between the functional responses of H. axyridis to the two aphid species.