Scientific Opinion on the assessment of the risk of solanaceous pospiviroids for the EU territory and the identification and evaluation of risk management options

Abstract

Following a request from the EU Commission, the EFSA PLH Panel conducted a risk assessment for the EU territory of pospiviroids affecting solanaceous crops, identified and evaluated risk reduction options and evaluated the EU provisional emergency measures targeting Potato spindle tuber viroid (PSTVd). The risk assessment included PSTVd, Citrus exocortis viroid, Columnea latent viroid, Mexican papita viroid, Tomato apical stunt viroid, Tomato chlorotic dwarf viroid, Tomato planta macho viroid, Chrysanthemum stunt viroid and Pepper chat fruit viroid. Four entry pathways were identified, three involving plant propagation material, with moderate probability of entry, and one involving plant products for human consumption, with low probability of entry. The probability of establishment was considered very high. Spread was considered likely within a crop and moderately likely between crop species, with exception of spread to potato, rated as unlikely. The probability of long distance spread within vegetatively propagated crops was estimated as likely/very likely. The direct consequences were expected to be major in potato and tomato, moderate in pepper, minimal/minor in other vegetables and minimal in ornamentals. Main risk assessment uncertainties derive from limited knowledge on pospiviroids other than PSTVd, although all pospiviroids are expected to have similar biological properties. Management options to reduce risk of entry, spread and consequences were identified and evaluated. No management options can prevent establishment. Examples of successful PSTVd eradication are linked to timely and strict implementation of measures. Uncertainty exists on the effectiveness of risk reduction strategies targeting only one pathway. The EU provisional emergency measures appeared to have significantly reduced PSTVd incidence in Solanum jasminoides and Brugmansia sp., even though eradication from the EU is so far incomplete. The low PSTVd incidence in food crops did not permit to conclude whether the reduction in PSTVd prevalence in ornamentals led to a reduction in outbreaks in food crops. © European Food Safety Authority, 2011. 1 On request from the European Commisssion, Question No EFSA-Q-2010-00911, adopted on 13 July 2011. 2 Panel members: Richard Baker, Thierry Candresse, Erzsebet Dormannsne Simon, Gianni Gilioli, Jean-Claude Gregoire, Michael John Jeger, Olia Evtimova Karadjova, Gabor Lovei, David Makowski, Charles Manceau, Maria Navajas, Angelo Porta Puglia, Trond Rafoss, Vittorio Rossi, Jan Schans, Gritta Schrader, Gregor Urek, Johan Coert van Lenteren, Irene Vloutoglou, Stephan Winter and Marina Zlotina. Correspondence: plh@efsa.europa.eu 3 Acknowledgement: The Panel wishes to thank the members of the Working Group on solanaceous pospiviroids: Thierry Candresse, Francesco Di Serio, Ricardo Flores, Adrian Fox, Rudra P. Singh, Jacobus Th. J. Verhoeven, Stephan Winter, for the preparatory work on this scientific opinion and EFSA staff Giuseppe Stancanelli, Svetla Kozelska, Olaf MosbachSchulz, Sara Tramontini and Tilemachos Goumperis for the support provided to this scientific opinion. 4 Editorial changes have been made on pages 20 and 21 (references corrected in table 5). These changes do not affect the overall conclusions of the opinion. To avoid confusion the original version has been removed from the website. Risk assessment of solanaceous pospiviroids 2 EFSA Journal 2011;9(8):2330