Plum Pox Potyvirus Disease of Stone Fruits

Plum pox potyvirus, the cause of the most destructive and most feared viral disease of Prunus, (plum pox or Sharka) has been established in North America. Following recognition of symptomatic peach fruit and the positive confirmation of the causal agent of the disease in October, 1999, an official announcement of the presence of the dreaded disease in Adams County, Pennsylvania was made jointly by the Animal & Plant Health Inspection Service and the Pennsylvania Department of Agriculture. Plum pox strains are capable of causing disease in peaches, plums, apricots, nectarines, almonds, sweet and sour cherries, as well as in other selected Prunus and non-Prunus species. Aphid-transmitted by more than 20 different aphid species in a stylet-borne manner, the virus also is spread by movement of nursery stock, budwood, and grafting. Control measures are discussed including development of a highly resistant transgenic plum line.