Input data needed for a risk model for the entry, establishment and spread of a pathogen (Phomopsis vaccinii) of blueberries and cranberries in the EU

International trade in live plant materials has increased worldwide over the last four decades. This has led to a dramatic increase in the introduction, establishment and spread of non-native plant pathogens. Regulatory authorities need advice on measures that may mitigate these adverse consequences of trade. Risk models may be used to underpin such advice. In this review, we give a systematic overview of the data needed for a quantitative risk model for Phomopsis vaccinii, which causes stem and fruit infections on Vaccinium species, and sometimes death, potentially also on native wild Vaccinium species in the EU. P. vaccinii is a quarantine organism worldwide, except for North America, where it is endemic. Despite extensive knowledge of the aetiology of the diseases caused by this pathogen and its taxonomy, quantitative data on transportation and detection of infected plants for planting and berries are scarce, and quantitative assessment of the future introduction, establishment and spread of P. vaccinii is difficult. Estimation of the potential impact of this pathogen in production fields and wild Vaccinium stands is even more difficult. P. vaccinii is not unique in this respect, and this review indicates the need for more and better quantitative data for assessment of the risks posed by newly introduced plant pathogens in areas where they are not endemic.