Update of the Scientific Opinion on the risks to plant health posed by Xylella fastidiosa in the EU territory

EFSA was asked to update the 2015 EFSA risk assessment on Xylella fastidiosa for the territory of the EU. In particular, EFSA was asked to focus on potential establishment, short‐ and long‐range spread, the length of the asymptomatic period, the impact of X. fastidiosa and an update on risk reduction options. EFSA was asked to take into account the different subspecies and Sequence Types of X. fastidiosa. This was attempted throughout the scientific opinion but several issues with data availability meant that this could only be partially achieved. Models for risk of establishment showed most of the EU territory may be potentially suitable for X. fastidiosa although southern EU is most at risk. Differences in estimated areas of potential establishment were evident among X. fastidiosa subspecies, particularly X. fastidiosa subsp. multiplex which demonstrated areas of potential establishment further north in the EU. The model of establishment could be used to develop targeted surveys by Member States. The asymptomatic period of X. fastidiosa varied significantly for different host and pathogen subspecies combinations, for example from a median of approximately 1 month in ornamental plants and up to 10 months in olive, for pauca. This variable and long asymptomatic period is a considerable limitation to successful detection and control, particularly where surveillance is based on visual inspection. Modelling suggested that local eradication (e.g. within orchards) is possible, providing sampling intensity is sufficient for early detection and effective control measures are implemented swiftly (e.g. within 30 days). Modelling of long‐range spread (e.g. regional scale) demonstrated the important role of long‐range dispersal and the need to better understand this. Reducing buffer zone width in both containment and eradication scenarios increased the area infected. Intensive surveillance for early detection, and consequent plant removal, of new outbreaks is crucial for both successful eradication and containment at the regional scale, in addition to effective vector control. The assessment of impacts indicated that almond and Citrus spp. were at lower impact on yield compared to olive. Although the lowest impact was estimated for grapevine, and the highest for olive, this was based on several assumptions including that the assessment considered only Philaenus spumarius as a vector. If other xylem‐feeding insects act as vectors the impact could be different. Since the Scientific Opinion published in 2015, there are still no risk reduction options that can remove the bacterium from the plant in open field conditions. Short‐ and long‐range spread modelling showed that an early detection and rapid application of phytosanitary measures, consisting among others of plant removal and vector control, are essential to prevent further spread of the pathogen to new areas. Further data collection will allow a reduction in uncertainty and facilitate more tailored and effective control given the intraspecific diversity of X. fastidiosa and wide host range.Additional co-authors: EFSA Panel on Plant Health (PLH), Wopke van der Werf, Antonio Vicent Civera, Jonathan Yuen, Lucia Zappalà, Donato Boscia, Gianni Gilioli, Rodrigo Krugner, Alexander Mastin, Anna Simonetto, Joao Roberto Spotti Lopes, Steven White, José Cortinas Abrahantes, Alice Delbianco, Andrea Maiorano, Olaf Mosbach‐Schulz, Giuseppe Stancanelli, Michela Guzzo, Stephen Parnel

Scientific Opinion on the risk to plant health posed by <em>Eutetranychus orientalis</em> Klein in the EU territory, with the identification and evaluation of risk reduction options

The Panel on Plant Health conducted a pest risk assessment for Eutetranychus orientalis in the European Union (EU) and evaluated the effectiveness of phytosanitary measures in Council Directive 2000/29/EC. Entry through the plants for planting pathway is assessed as very likely, while entry through other pathways is estimated as moderately likely to unlikely owing to the different probability of transfer to a suitable host. Establishment is rated as very likely in Mediterranean areas and from moderately likely to unlikely in non-Mediterranean areas, because of unfavourable environmental conditions. Spread is rated as very likely because of the many ways the pest can spread, its polyphagy and the wide distribution of hosts. Impact is rated as minor, with an expected increase in the damage when populations of natural enemies are severely affected by control measures and/or when environmental conditions are stressful for the host. However, the lack of information resulted in an overall medium level of uncertainty. The Panel evaluated the effectiveness of current EU phytosanitary measures and concluded that the removal of E. orientalis from Annex IIAII would not affect its probability of entry, because the importation from Third countries of some host plants regulated for this pest(Citrus, Fortunella, Poncirus species and their hybrids) is prohibited in Annex III. However, spread could be affected since there would no longer be a requirement to inspect for this pest before issuing a plant passport (Annex V). However, since the regulated Rutaceae species constitute an extremely small proportion of the potential host plants of E. orientalis, the current phytosanitary measures are mostly ineffective in preventing further introduction and spread of E. orientalis in the EU. The Panel identified surveillance at the production site and treatment of the consignment as the most effective and technically feasible risk reduction options, particularly when applied together