Pest risk assessment made by France on Citrus chlorotic dwarf virus considered by France as harmful in the French overseas departments of French Guiana, Guadeloupe, Martinique and Réunion - Scientific Opinion of the Panel on Plant Health

Abstract

Following a request from the European Commission, the EFSA Panel on Plant Health was asked to deliver a scientific opinion on 30 pest risk assessments made by France on organisms which are considered by France as harmful in four French overseas departments, i.e. French Guiana, Guadeloupe, Martinique and Reunion. In particular, the Panel was asked whether these organisms can be considered as harmful organisms for the endangered area of the above departments, in the meaning of the definition mentioned in Article 2.1.(e) of Directive 2000/29/EC and thus potentially eligible for addition to the list of harmful organisms in Directive 2000/29/EC. This document presents the opinion of the Panel on Plant Health on the simplified[1] pest risk assessment conducted by France on Citrus chlorotic dwarf virus, with French Guiana, Guadeloupe, Martinique and Reunion considered as endangered area. The Panel will use the name Citrus chlorotic dwarf (CCD) agent in the following text, as the causal agent of citrus chlorotic dwarf disease has not yet been identified. CCD is a virus-like disease that can affect almost all citrus species and cultivars. The causal agent is transmitted by the bayberry whitefly Parabemisia myricae Kuwana (Homoptera: Aleyrodidae) in a persistent or semi-persistent manner. In addition CCD is transmitted by grafting and can be experimentally transmitted by mechanical inoculation. The Panel examined in detail the risk assessment provided, and considered the accuracy and quality of the information provided and of the methods applied for pest risk assessment purposes. The review was based on the principles and terminology of the International Standard on Phytosanitary Measures ISPM No. 11[2] [Pest risk analysis for quarantine pests including analysis of environmental risks and living modified organisms (2004)] and the terminology of ISPM No. 5 [Glossary of Phytosanitary Terms (2007)] by the International Plant Protection Convention (FAO, 2007). The simplified assessment provides limited evidence to justify the ratings given in the assessment. It concludes that the phytosanitary risk associated with CCD disease is low to moderate. After analysis of the French document, the references cited and additional references and in consultation with experts in Turkey, the Panel considers that the overall phytosanitary risk posed by the CCD agent is underestimated in the assessment provided. The Panel concludes that: * Although the causal agent of the CCD disease is not yet characterised, it produces distinct and consistent symptoms. * The CCD agent is graft transmissible and can be reliably detected although not identified by biological indexing. * The disease is currently restricted to the eastern Mediterranean region of Turkey * The CCD agent is effectively transmitted in a semi-persistent or persistent manner by the bayberry whitefly, Parabemisia myricae, which is present in Guadeloupe. Uncertainty exists over the presence of this vector in the other French overseas departments under consideration. * The main pathway of entry is through the import, from Turkey, of citrus plants or budwood for multiplication. * If the CCD agent was to be introduced, it would remain in the French overseas departments for at least as long as the infected material is cultivated and propagated and, at least in Guadeloupe, it is likely to spread to other citrus plants through vector activity. * Severe losses are reported in almost all citrus species with the exception of sweet orange which shows tolerance to the disease but may, however, act as source of inoculum. * Once the CCD agent is introduced in a citrus growing area, it would be difficult if not impossible to control and/or to eradicate. * Preventing entry of citrus plant material coming from the affected area would reduce the risks to the PRA area[3] to a negligible level. * While the CCD agent can be detected by bioassays as a disease causing agent, its unequivocal identification is pending. * A significant level of uncertainty also exists over the presence of P.myricae in the French overseas departments other than Guadeloupe. Overall, the Panel considers the CCD agent appropriate for analysis of risk management options for the French overseas departments of French Guiana, Guadeloupe, Martinique and Reunion and thus potentially eligible for addition to the list of harmful organisms in Directive 2000/29/EC. The Panel notes, in addition, that the CCD agent may pose a risk to other citrus-growing areas in the European Union, particularly areas where the vector is present (e.g. Spain), and which lie closer to Turkey, the area where the disease is present. The Panel therefore recommends further assessment of the risks posed for the wider PRA area of the EU