Genetic diversity and dynamics of plum pox virus populations in the alternative host American plum

Plum pox virus (PPV) is a serious viral threat to stone fruit trees worldwide. Wild Prunus species including American plum (Prunus americana) can serve as sources of inoculum. High-throughput sequencing was used to characterize PPV populations in American plum and peach after aphid inoculation and after two cycles of cold-induced dormancy (CID). A significant decrease in the number of sequence variations in the PPV genome was observed after CID in American plum, but not in peach. Seventeen were identified as unique to American plum, while eight were unique to peach. These findings provide insight into the genetic diversity of PPV in a potential reservoir host.