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Scientific Opinion on the Risk to Plant Health of Xanthomonas Citri Pv

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Scientific Opinion on the Risk to Plant Health of Xanthomonas Citri Pv EFSA Journal 20YY;volume(issue):NNNN 1 SCIENTIFIC OPINION 2 Scientific Opinion on the risk to plant health of Xanthomonas citri pv. citri 1 3 and Xanthomonas citri pv. aurantifolii for the EU territory 4 EFSA Panel on Plant Health (PLH)2, 3 5 European Food Safety Authority (EFSA), Parma, Italy 6 Endorsed for public consultation on 24 July 2013 7 8 ABSTRACT 9 The Panel conducted a pest risk assessment for Xanthomonas campestris (all strains pathogenic to Citrus) for the 10 EU territory including identification, evaluation of risk management options and assessment of the effectiveness 11 of present EU requirements against Xanthomonas strains pathogenic to citrus. The strains of X. campestris 12 pathogenic to citrus have been reclassified as four distinct pathovars. Only two pathovars (X. citri pv. citri, X. citri 13 pv. aurantifolii) are responsible for citrus bacterial canker that presents a major risk for the citrus industry in the 14 EU. Seven entry pathways have been identified and evaluated. The likelihood of entry is rated unlikely for fruit 15 and leaves, likely for fruit plants for planting and moderately likely for ornamental plants for planting. The 16 probability of establishment is rated as moderately likely to likely because host plants are widely present where 17 environmental conditions are frequently suitable. Once established, spread would be likely because of human 18 activities and suitable weather conditions. The impact of the disease, even if control measures are applied, could 19 be moderate to major. The disease would cause yield losses, negative social incidence in areas where citrus is the 20 main crop, costly control measures and create environmental problems. The combined EU regulations have 21 shown to be effective in preventing the introduction of X. citri pv. citri or X. citri pv. aurantifolii in the EU, as 22 no outbreaks of citrus canker in the EU territory have been reported. © European Food Safety Authority, 20YY 23 24 KEY WORDS 25 Xanthomonas citri pv. citri, Xanthomonas citri pv. aurantifolii, citrus canker, European Union, pest risk 26 assessment, risk reduction option 27 1 On request from European Commission, Question No EFSA-Q-YYYY-NNNN, adopted on DD Month YYYY. 2 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: [email protected] 3 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. Suggested citation: EFSA PLH Panel (EFSA Panel on Plant Health), 20YY. Scientific Opinion on the risk to plant health of Xanthomonas citri pv. citri and Xanthomonas citri pv. aurantifolii for the EU territory. EFSA Journal 20YY;volume(issue):NNNN, 162 pp. doi:10.2903/j.efsa.20YY.NNNN Available online: www.efsa.europa.eu/efsajournal © European Food Safety Authority, 20YY Xanthomonas citri pv. citri and Xanthomonas citri pv. aurantifolii pest risk assessment 28 SUMMARY 29 Following a request from European Commission, the Panel on Plant Health has been asked to deliver a 30 scientific opinion on the pest risk posed by Xanthomonas campestris (all strains pathogenic to Citrus) 31 for the EU territory, to identify risk management options and to evaluate their effectiveness in 32 reducing the risk to plant health posed by this harmful organism. In particular, the Panel has been 33 asked to provide an opinion on the effectiveness of the present EU requirements against Xanthomonas 34 campestris (all strains pathogenic to Citrus), which are listed in Annex III, IV and V of Council 35 Directive 2000/29/EC4, as well as in Commission Decision 2004/416/EC5 and Commission Decision 36 2006/473/EC6, in reducing the risk of introduction of this pest into the EU territory. In addition the 37 Panel has been asked to provide, guidance on the right denomination of this harmful organism. The 38 Panel has been also asked to address the comments submitted in April 2012 by the US phytosanitary 39 authorities in response to the recent EFSA opinion of on a US request regarding the export of Florida 40 citrus fruit to the EU (EFSA Journal 2011;9(2):2461). However the comments are not addressed in this 41 opinion as they will be discussed in a separate document. 42 The strains of X. campestris pathogenic to Citrus have been reclassified as four distinct species. X. citri 43 pv. citri and X. citri pv. aurantifolii are the two bacteria responsible for citrus canker disease and the 44 only ones significantly impacting the citrus industry. The X. alfalfae subsp. citrumelonis and X. citri 45 pv. bilvae are not responsible for citrus canker. 46 Citrus bacterial canker (CBC) caused by X. citri pv. citri or X. citri pv. aurantifolii, presents a major 47 risk to the EU territory for the citrus industry because the causal agents of the disease has the potential 48 for causing consequences in the risk assessment area once it establishes as hosts are present and the 49 environmental conditions are favorable. Citrus is a major crop in Mediterranean countries where the 50 environmental conditions required for the establishment of X. citri pv. citri or X. citri pv. aurantifolii 51 are potentially met in many places. 52 The Panel conducted the risk assessment following the general principles of the ―Guidance on a 53 harmonised framework for pest risk assessment and the identification and evaluation of pest risk 54 management options‖ (EFSA Panel on Plant Health (PLH), 2010) and of the ―Guidance on evaluation 55 of risk reduction options‖ (EFSA Panel on Plant Health (PLH), 2012). The Panel conducted the risk 56 assessment considering the scenario of absence of the current requirements against Xanthomonas 57 campestris (all strains pathogenic to Citrus), which are listed in Annex II, III, IV and V of Council 58 Directive 2000/29/EC, as well as in Commission Decision 2004/416/EC, Commission Decision 59 2006/473/EC and Commission Implementing Decision 2013/67/EU7. However it is assumed that 60 citrus exporting countries still apply measures voluntarily, or in response to requirements by non EU 61 importing countries. 62 4 Council Directive 2000/29/EC of 8 May 2000 on protective measures against the introduction into the Community of organisms harmful to plants or plant products and against their spread within the Community. Official Journal of the European Communities L 169/1, 10.7.2000, pp. 1–112. 5 Commission Decision 2004/416/EC of 29 April 2004 on temporary emergency measures in respect of certain citrus fruits originating in Argentina or Brazil. Official Journal of the European Communities L 151, 30.4.2004, p. 76–80. 6 Commission Decision 2006/473/EC of 5 July 2006 recognising certain third countries and certain areas of third countries as being free from Xanthomonas campestris (all strains pathogenic to Citrus), Cercospora angolensis Carv. et Mendes and Guignardia citricarpa Kiely (all strains pathogenic to Citrus). Official Journal of the European Communities L 187, 8.7.2006, p. 35–36. 7 Commission Implementing Decision 2013/67/EU of 29 January 2013 amending Decision 2004/416/EC on temporary emergency measures in respect of certain citrus fruits originating in Brazil. Official Journal of the European Union L 31, 31.1.2013, p. 75-76. EFSA Journal 20YY;volume(issue):NNNN 2 Xanthomonas citri pv. citri and Xanthomonas citri pv. aurantifolii pest risk assessment 63 After consideration of the evidence, the Panel reached the following conclusions: 64 With regard to the assessment of the risk to plant health for the EU territory: 65 Under the scenario of absence of the current specific EU plant health legislation and the assumption 66 that citrus exporting countries still apply measures voluntarily or as required by non EU importing 67 countries, the conclusions of the pest risk assessment are as follows: 68 Entry 69 Under a scenario of absence of X. citri pv. citri and X. citri pv. aurantifolii official EU regulation, the 70 probability of entry has been rated as unlikely for the fruit pathways and as likely for the plants for 71 planting pathways. 72 73 For fruits, the probability of entry is rated unlikely because: 74 - the association with the pathway at origin is likely for commercial trade based on the high 75 volume of citrus fruits imported within the EU from countries where citrus canker is reported, 76 with documented reports of interceptions. The association with the passenger pathway is rated 77 likely to very likely based on the lack of control measures through regulation and 78 packinghouse processes for domestic markets as well as a lower awareness to the disease by 79 passengers; 80 - the ability of bacteria to survive during transport, verified by the isolation of X. citri pv. citri 81 or X. citri pv. aurantifolii, is rated very likely; 82 - the probability of the pest surviving existing management procedure is very likely, since no 83 specific measure is currently in place in the RA area; 84 - the probability of transfer to a suitable host is rated unlikely, based on the litterature currently 85 available on effective fruit transfer to plants. The rating is not very unlikely as this transfer 86 could occur because of presence of waste near to orchards and sometime short distance 87 between tree canopy and soil in the RA area and because of occurrence of climatic conditions 88 suitable for the transfer.
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