Potato plants produce a blend of volatile organic compounds (VOCs), including green leaf volatiles, monoterpenes, and sesquiterpenes. Prior work has shown that some VOC are elevated in the headspace of Potato leafroll virus (PLRV)-infected potato plants. This PLRV-infection-induced VOC blend elicits physiological and behavioral responses from the green peach aphid (GPA), M. persicae, the principal vector of PLRV. The VOC responsible for the aphid responses have not been identified. In this study we sought to determine the behaviorally active compounds using bioassay guided subtractive fractionation of synthetic blends and actual VOC collected from headspace of PLRV infected and non-infected potato plants. A synthetic blend containing all the compounds elevated in headspace of PLRV infected potato plants is more arrestant than a synthetic blend based on VOCs emitted by healthy plants. Subtractive fractionation showed that the synthetic blend lacking any one of three fractions (green leaf volatiles, monoterpenes, sesquiterpenes) loses the arrestant activity and that this effect was greatest for the monoterpene fraction. We complemented this study with bioassays using preparative gas chromatography to fractionate headspace volatiles collected from both PLRV infected and uninfected potato plants. Current results suggest that the entire blend is highly attractive to the green peach aphid and is responsible for generating full behavioral response by M. persicae to VOCs from PLRV infected potato plants.

Species 1: Hemiptera Aphididae Myzus persicae (Green peach aphid)