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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 that presents 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.

The Panel on Plant Health conducted a pest risk assessment for the grapevine insect pest, Daktulosphaira vitifoliae (an aphid species commonly known as phylloxera), in the European Union, identified risk reduction options and evaluated the effectiveness of the phytosanitary measures listed in Council Directive 2000/29/EC. Entry was assessed as potentially very likely for plants intended for planting (although the pathway is closed by Article 15 of Annex III) and very unlikely for fruit for consumption because transport and transfer would be very difficult, even though phylloxera has a moderate likelihood of association with the pathway. Establishment is very likely as the pest is already very widespread in the risk assessment area, occurring almost everywhere Vitis plants are present. Successful eradication is very unlikely and small populations can persist undetected in the soil. Spread within the EU is considered to be very likely because there are no effective barriers, it can disperse up to a few kilometres aided by the wind and it can readily be moved long distances with planting material. Grafting with resistant rootstocks throughout the EU ensures that the production of fruit and plants for planting is rarely affected by phylloxera infestations and, if so, only at a limited level. The Panel considers that the IIAII measures for D. vitifoliae do not assist in preventing entry and are ineffective in preventing spread because detection is so difficult. Restricting movements of plants for planting to cuttings grafted on resistant rootstocks, in combination with treatments (e.g. particularly fungicides and hot water treatments), was found to be the most effective risk reduction option. Limitations in the Cyprus protected zone regulations were identified.

The Panel conducted a risk assessment of Phyllosticta citricarpa for the EU. P. citricarpa causes citrus black spot (CBS) and is absent from the EU. Under the scenario of absence of specific risk reduction options against P. citricarpa, the risk of entry of P. citricarpa was rated as likely for citrus plants for planting and citrus fruit with leaves, moderately likely for citrus fruit without leaves, unlikely for citrus leaves for cooking and very unlikely for Tahiti lime fruit without leaves. Establishment was rated as moderately likely because susceptible hosts are widely available and environmental conditions in many EU citrus-growing areas are suitable (with high uncertainty) for P. citricarpa ascospore production, dispersal and infection. Current fungicide treatments will not prevent establishment. Environmental favourability is increased by the use of sprinkler and micro-sprinkler irrigation in some EU citrus-growing locations. Spread with trade was rated as moderately likely. Model results indicate that CBS epidemics are most likely to develop in EU citrus-growing areas in late summer to early autumn and in some locations also in late spring to early summer. CBS is expected to affect mainly lemons and late-maturing sweet orange and mandarin varieties, with moderate negative consequences for the production of fresh fruit, but with environmental impact of additional fungicide treatments. Negative consequences would be minor for early-maturing citrus varieties and minimal for citrus for processing. Uncertainty concerning the consequences is high, mainly because of the lack of data on critical climate response parameters for the pathogen but also because information on impact in areas at the limits of the current distribution is scarce. Since eradication and containment are difficult, phytosanitary measures should focus on preventing entry. Current phytosanitary measures are evaluated to be effective, with the exception of pest-free production sites.

The Panel on Plant Health assessed the risk to plant health from Phytophthora fragariae for the European Union and evaluated the current EU legislation and possible risk reduction options. The pest is present in most areas of Europe except southern Mediterranean regions. Entry through the plants for planting, but not seeds, pathway, is assessed as a major pathway, with the probability of entry rated as unlikely and the uncertainty as high. The probability of establishment is likely in the absence of existing disease control practices with low uncertainty. The probability of spread in the absence of a scheme for the production of certified plants for planting is considered to be very likely. With certification, spread is considered to be unlikely to moderately likely, depending on the inclusion of testing for the pathogen as part of certification. These ratings have medium uncertainty. Potential impact is rated as minor with medium uncertainty. The Panel evaluated the effectiveness of current EU legislation regarding the introduction and spread of P. fragariae. According to the regulation the import of Fragaria plants for planting, other than seeds, is prohibited from specified countries, whereas for import of these plants from other countries and for movement of these plants within the EU special requirements with respect to P. fragariae must be fulfilled. If the current legislation specific to P. fragariae were removed, no major consequences would be expected, unless the industry simultaneously ceased its voluntary certification activity. This is largely because of the important level of protection afforded to the industry by the widely used certification schemes for Fragaria, which significantly reduce the risks of entry, establishment, spread and impact. Certification schemes for the movement of Fragaria plants for planting offer the greatest efficiency and feasibility and the least uncertainty, especially if effective detection is incorporated into them.

The Panel on Plant Health conducted a pest risk assessment for Liriomyza huidobrensis and Liriomyza trifolii in the European Union and identified and evaluated the phytosanitary measures listed in Council Directive 2000/29/EC. Entry on the principal pathways (plants for planting, cut flowers and leafy vegetables) is assessed as likely as the pests are regularly associated with the pathways at origin, survival during transport or storage is high and only partially affected by current pest management procedures, and transfer to a suitable host is likely as their hosts are so widespread. Establishment is rated as very likely because both species have established populations in most countries of the EU, with transient populations occurring outdoors in non-Mediterranean areas. Spread within the EU is considered to be likely because the pests can readily be moved with plant material. The magnitude of the potential consequences is rated as minor for both species in Mediterranean areas. In non-Mediterranean countries it is moderate for both species in protected crops but, outdoors, impacts are minor for L. huidobrensis and minimal for L. trifolii. The current regulations to prevent entry and spread were found to be only partially effective as interceptions are still being made, cut branches with foliage and leafy vegetables other than celery are excluded, and the methods for inspection and the treatments required to confirm pest free areas, places of production and consignments are not clearly specified. Removal of the legislation would have some advantages and disadvantages but may not have a major effect. The regulations could be tightened by including additional commodities, clearly prescribing the inspection procedures and the appropriate treatments to be used and combining these with other measures, e.g. screening. The application of protected zones to areas where the pests are not yet present can be applied to help prevent further spread.

The Panel on Plant Health conducted a pest risk assessment for Chrysanthemum stunt viroid (CSVd) and identified and evaluated risk reduction options, particularly those listed in Council Directive 2000/29/EC. Three entry pathways were identified, with plants for planting being the most important and rated as moderately likely. CSVd is recorded in some EU Member States with a limited distribution and is regulated on chrysanthemum; host plants are widely cultivated in greenhouses and outdoors. Therefore, establishment is very likely. Shortdistance spread within a crop is likely, whereas short-distance spread between different species is unlikely to moderately likely. For vegetatively propagated species, in the absence of an efficient certification system, longdistance spread is very likely and a major impact would be expected on chrysanthemum, with associated yield and quality losses. However, under the existing certification scheme for chrysanthemum plant propagation material, the probability of spread through infected cuttings is largely reduced and the direct consequences of viroid outbreaks are expected to be minor. Minimal impact is predicted for other ornamental hosts and a minor impact for solanaceous vegetable crops. The indirect effects of CSVd are considered to be limited, with the exception of eradication. Risk reduction options addressing the sanitary status of the propagation material are likely to be the most effective and feasible. These include the current EU measures, as well as a statutory certification system with associated statutory import requirements or, failing that, but potentially less effective, the use of voluntary industry standards. It is difficult to disentangle the benefits of the current legislation from those of the industry-developed chrysanthemum certification system. The high efficacy of current measures is supported by the absence or limited presence of CSVd in the EU and by the limited number of interceptions and findings. Possib