• Open Access

Scientific Opinion on the risk to plant health of Xanthomonas citri pv. citri and Xanthomonas citri pv. aurantifolii for the EU territory


  • EFSA Panel on Plant Health (PLH)

  • Panel members: Richard Baker, Claude Bragard, Thierry Candresse, Gianni Gilioli, Jean-Claude Grégoire, Imre Holb, Michael John Jeger, Olia Evtimova Karadjova, Christer Magnusson, David Makowski, Charles Manceau, Maria Navajas, Trond Rafoss, Vittorio Rossi, Jan Schans, Gritta Schrader, Gregor Urek, Johan Coert van Lenteren, Irene Vloutoglou, Stephan Winter and Wopke van der Werf
  • Correspondence: alpha@efsa.europa.eu
  • Acknowledgement: The Panel wishes to thank the members of the Working Group on Citrus canker pest risk assessment: Claude Bragard, David Caffier, Charles Manceau, Olivier Pruvost Jan Schans and Christian Vernière for the preparatory work on this Scientific Opinion and EFSA staff: Svetla Kozelska, Tilemachos Goumperis and Olaf Mosbach Schulz for the support provided to this Scientific Opinion.
  • Adoption date: 30 January 2014
  • Published date: 21 February 2014
  • Question number: EFSA-Q-2012-00928
  • On request from: European Commission


The Panel conducted a pest risk assessment for Xanthomonas campestris (all strains pathogenic to Citrus) for the EU territory and an assessment of the effectiveness of present EU requirements against Xanthomonas strains pathogenic to citrus. The risk assessment was conducted under the scenario of absence of the current specific EU plant health legislation and the assumption that citrus-exporting countries apply measures to reduce yield and quality losses. Risk reduction options were systematically identified and evaluated. The strains of X. campestris pathogenic to citrus have been reclassified as four distinct infraspecific taxa within two species: X. citri and X. alfalfae. Only two pathovars (X. citri pv. citri and X. citri pv. aurantifolii) are responsible for the citrus bacterial canker thatpresents a major risk for the citrus industry in the EU. Seven entry pathways have been identified and evaluated. The likelihood of entry was rated unlikely for fruit, very likely for fruit plants for planting, moderately likely for ornamental plants for planting and unlikely for leaves and twigs. The uncertainty of probability of entry was rated as high. The probability of establishment was rated as moderately likely to likely with a medium uncertainty because host plants are widely present in EU areas where environmental conditions are suitable. Once established, spread would be likely with a low uncertainty. The impact of the disease, even if control measures are applied, was rated as moderate to major with a medium uncertainty. The disease would cause yield losses in areas where citrus is the main crop, increase the need for control measures and create environmental problems. The combined EU regulations have been shown to be effective in preventing the introduction of X. citri pv. citri or X. citri pv. aurantifolii in the EU, as no outbreaks of citrus canker in the EU territory have been reported.