Seasonal activity and biological control of large raspberry aphid (Amphorophora agathonica) in northern Washington

The large raspberry aphid, Amphorophora agathonica, has been implicated in the transmission of viruses in raspberry in the Pacific Northwest region of the United States. These viruses result in severe foliage decline and a fruit disorder, rendering the fruit unmarketable. As a result, A. agathonica control has become a research priority. In order to learn more about control options of A. agathonica, field and laboratory studies were conducted during the summer of 2010 to determine aphid phenology and biological control agents naturally present in the region. In the field, aphids were collected weekly and reared in the laboratory to identify parasitoids and entomopathenogenic fungi that target A. agathonica. In the lab, aphids were reared at 7, 12, 17, 22, and 27°C and growth was monitored daily to determine thermal constants and developmental thresholds. Results and implications for management in the Pacific Northwest region will be discussed.