Unfolding the secrets of plum pox virus: from epidemiology to genomics

Over an approximately 80-year period since the description of the Sharka disease, the plum pox virus (PPV) has been thoroughly studied on various levels of the infection cycle. World-wide distribution of the virus, severity of the disease for the fruit industry with a potential to be further increased and discovery/emergence of new strains make PPV the most epidemiologically important viral pathogen of stone fruit trees. The history of PPV research reflects the development of analytical methods applicable in plant virology. In particular the establishment of molecular biology with reverse genetics and improvement of DNA sequencing technology have further contributed to the increase in knowledge on PPV variability, evolution, replication and interaction with host plants. This review gives a comprehensive summary of PPV data accumulated progressively, from the biological characterization of the disease to recent attempts aimed at using the PPV-based vectors for expression of exogenous proteins in plants.