Raspberry viruses affect the behavior and performance of Amphorophora agathonica in single and mixed infections

Pathogens may alter their hosts, which consequently increases transmission efficiency by vectors. We examined the effects of Raspberry leaf mottle virus [RLMV; Closterovirus (Closteroviridae)] and Raspberry latent virus [RpLV; Reovirus (Reoviridae)], alone and in a co-infection in raspberry, Rubus idaeus L. (Rosaceae) cv. Meeker, on the behavior and performance of its vector, Amphorophora agathonica Hottes (Hemiptera: Aphididae). Longevity was increased in aphids feeding on all infected-plant treatments compared with healthy plants, but aphid fecundity only increased in the co-infection treatment. In a two-way choice study between infected and healthy plants, aphids showed no difference in preference between plants after 30 min of exposure. After 24 h, aphids significantly preferred to settle on plants infected with RLMV over healthy, but healthy plants over plants infected with RpLV. There were no differences in settling preferences between healthy and co-infected plants. An electrical penetration graph study showed no differences in aphid feeding behavior on plants infected with RLMV and RLMV+RpLV when compared with healthy controls. Our results are consistent with past findings that infected plant’s impact vector performance and behavior, but also highlight the need to further investigate greater virus diversity and effects of mixed infections.