OCCURRENCE AND CONTROL OF PLUM POX VIRUS IN THE NETHERLANDS

In the Netherlands the first infections with Plum pox virus (PPV) have been found in plum trees in 1965. However, indications exist that the virus was introduced via imports of infected rootstocks around 1960. Therefore, the virus had been able to spread over the country before its first finding. Its finding in 1965, however, has been reason for initiating eradication campaigns in nurseries, orchards and private gardens. These campaigns succeeded in the eradication of the virus from nurseries. In orchards the incidence decreased to a low prevalence thanks to the support of the growers which were financially compensated. The success of the campaign got further support from the ‘virus project’ that provided virus-free planting material for the growers. In addition, the natural spread by aphids appeared limited under Dutch conditions. As a result, nowadays PPV is only very rarely found in nurseries and is occurring at low levels in orchards. In the case where infections are found, adequate measures are taken to eradicate the virus. The availability of certified virus-free planting material greatly contributes to the control of PPV; however, the PPV status of imported Prunus trees from outside the EU and of CAC trees produced in the European Union pose a threat for the near future.