Occurrence and Eradication Strategies of Plum Pox Virus in Japan

Plum pox virus (PPV) was first detected in Japan in April 2009 in orchards of Japanese apricot (Prunus mume) in the Tokyo metropolitan area. Symptoms comprised ring spots on leaves, color breaking on petals, and pale rings and deformities on the fruit. All isolates were confirmed as strain "D". After the first detection in Tokyo, a nationwide survey for PPV was conducted. As a result, PPV infection was detected in five cities within the Tokyo metropolitan area and two cities outside the area in 2009; by July 2010, PPV was found in two additional cities in the Tokyo metropolitan area and four additional cities outside the area. Infected nursery stock in five cities outside the Tokyo area originated from the infected nursery stock in the Tokyo area. All PPV-infected trees outside the Tokyo area were eliminated immediately or soon after and a subsequent intensive survey confirmed that there was no infection in the surrounding areas. Infected areas were specified based on delimiting surveys conducted until September 2009. The MAFF established regulated areas under a ministerial ordinance enforced in February 2010. The ordinance prohibits the movement of PPV host plants from the regulated areas and stipulates the elimination of PPV-infected plants. Monitoring surveys in the regulated areas and nationwide detection surveys for PPV will be continued after 2010. The MAFF concludes that the status of PPV in Japan is 'Present: under eradication', under IPPC standards (ISPM No. 8).