Search

The Panel on Plant Health performed a pest categorisation of the six-toothed bark beetle, Ips sexdentatus (B€orner) (Coleoptera: Curculionidae, Scolytinae), for the EU. I. sexdentatus is a well-defined and distinguishable species, native to Eurasia and recognised mainly as a pest of pine (Pinus spp., in the pest’s whole range) and spruce (mainly Picea orientalis in Turkey and Georgia). It also might occasionally attack Larix spp. and Abies spp. It is distributed throughout the EU (24 Member States). It is a protected zone quarantine pest in Ireland, Cyprus and the United Kingdom (Northern Ireland, Isle of Man), listed in Annex IIB of Council Directive 2000/29/EC. Wood, wood products, bark and wood packaging material are considered as pathways for this pest, which is also able to disperse by flight over tens of kilometres. The adults normally establish on fallen or weakened trees (e.g. after a fire or a drought) and can also massattack healthy trees. The males produce aggregation pheromones that attract conspecifics of both sexes. The insects also inoculate pathogenic fungi to their hosts. There are one to five generations per year. The wide current geographical range of I. sexdentatus suggests that it is able to establish anywhere in the EU where its hosts are present. Sanitary thinning or clear-felling are the major control methods. Pheromone mass-trapping is also locally implemented. Quarantine measures are implemented to prevent entry into the protected zones. All criteria for consideration as potential protected zone quarantine pest are met. The criteria for considering I. sexdentatus as a potential regulated non-quarantine pest are not met since plants for planting are not viewed as a pathway.

The Panel on Plant Health performed a pest categorisation of the large larch bark beetle, Ips cembrae (Heer) (Coleoptera: Curculionidae, Scolytinae), for the EU. I. cembrae is a well-defined and distinguishable species, native to Europe and recognised mainly as a pest of larch (Larix spp.) and occasionally of pine (Pinus spp.) and spruce (Picea spp.). It is distributed in 16 Member States of the EU and listed in Annex IIB of Council Directive 2000/29/EC. Protected zones are in place in Greece, Ireland and the United Kingdom (Northern Ireland and Isle of Man). Wood, wood products, bark and wood packaging material are considered as pathways for this pest, which is also able to disperse by flight. The insects normally establish on fallen or weakened trees but, when their populations are high, can also mass-attack healthy trees. The males produce aggregation pheromones that attract conspecifics of both sexes. The insects also inoculate pathogenic fungi to their hosts. There are one to two generations per year. Before establishing their broods, the young adults need to proceed to maturation feeding either within the bark of the tree where they developed or in 2–18 years old twigs. I. cembrae has been expanding its geographical range in Europe during the second half of the 20th century. Sanitary thinning or clear felling is the major control methods. Quarantine measures are implemented to prevent entry in the protected zones. All criteria for consideration as potential protected zone quarantine pest are met. The criteria for considering I. cembrae as a potential regulated non-quarantine pest are not met since plants for planting are not viewed as a major pathway.

Given the large number of alien species that may potentially develop into invasives, there is a clear need for robust schemes that allow to screen species for such risks. The Harmonia+ framework presented here brings together 30 questions that refer to distinct components of invasion. Together, they cover the stages of introduction, establishment, spread, and multiple kinds of impacts, viz. referring to the health of the environment (including wild species), cultivated plants, domesticated animals and man. In a complete assessment, input is provided by choosing among predefined ordinal answers and by supplementing these with textual clarification. Uncertainty is covered by indicating levels of confidence. By converting answers into scores, which are then condensed into summary statistics, Harmonia+ allows for quantitative output on stage-specific and general risks. Test assessments on five species emerging in Belgium showed the perceived environmental risks of Procambarus clarkii to be highest (0.72), and that of Threskiornis aethiopicus to be lowest (0.13). Given the considerable parallels that exist between invasive alien species and emerging infectious diseases, we additionally created Pandora, which is a risk analysis scheme for pathogens and parasites. It consists of 13 key questions and has the same structure as Harmonia+. Since diseases play a paramount role in biological invasions, results of Pandora assessments may feed into Harmonia+ through a slightly adapted, host-specific version named Pandora+. Harmonia+, Pandora and Pandora+ may be used both for prioritization purposes and for underpinning detailed risk analyses, and can be consulted online through http://ias.biodiversity.be

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. © European Food Safety Authority, 2012

The Panel on Plant Health has delivered a scientific opinion on the different risks posed by European and non-European populations of the potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis to solanaceous plants in the EU and on the effectiveness of current control measures. Although PCN, particularly G. rostochiensis, are widespread in the EU, crop damage is limited because breeders have been able to develop varieties that are resistant to the small number of genotypes that are present. These genotypes represent a minor subset of the gene pool and virulence that is present in South America. As new South American genotypes are very likely to have a similar potential for establishment and spread as existing European genotypes, the potato varieties currently grown in Europe will not be resistant to new virulent genotypes. As resistant varieties take a very long time to develop, the consequences of a new introduction of South American PCN would be major. The Panel therefore concluded that it is very important to maintain the current phytosanitary measures to prevent the entry of South American PCN. However, uncertainties over the effectiveness of the measures in Annex IVAI relating to place of production freedom and soil origin were noted, and the Panel identified additional risk reduction options for certain plants for planting (e.g. bulbs) and additional requirements to confirm the absence of PCN in places of production. The Panel also identified some problems with the existing control measures to reduce the spread of PCN within the EU. A thorough and well-coordinated EU-wide survey using standardized methods would be necessary to evaluate the need to maintain these measures. The monitoring of PCN populations should exploit new diagnostic techniques (e.g. mitochondrial DNA sequences) to ensure that the resistance available is deployed appropriately. The Panel on Plant Health has delivered a scientific opinion on the different risks posed by European and non-European populations of the potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis to solanaceous plants in the EU and on the effectiveness of current control measures. Although PCN, particularly G. rostochiensis, are widespread in the EU, crop damage is limited because breeders have been able to develop varieties that are resistant to the small number of genotypes that are present. These genotypes represent a minor subset of the gene pool and virulence that is present in South America. As new South American genotypes are very likely to have a similar potential for establishment and spread as existing European genotypes, the potato varieties currently grown in Europe will not be resistant to new virulent genotypes. As resistant varieties take a very long time to develop, the consequences of a new introduction of South American PCN would be major. The Panel therefore concluded that it is very important to maintain the current phytosanitary measures to prevent the entry of South American PCN. However, uncertainties over the effectiveness of the measures in Annex IVAI relating to place of production freedom and soil origin were noted, and the Panel identified additional risk reduction options for certain plants for planting (e.g. bulbs) and additional requirements to confirm the absence of PCN in places of production. The Panel also identified some problems with the existing control measures to reduce the spread of PCN within the EU. A thorough and well-coordinated EU-wide survey using standardized methods would be necessary to evaluate the need to maintain these measures. The monitoring of PCN populations should exploit new diagnostic techniques (e.g. mitochondrial DNA sequences) to ensure that the resistance available is deployed appropriately.

In 2011, the EFSA Panel on Plant Health was asked by the European Commission to provide an opinion on a technical file submitted by the US Authorities to support a request to list a new heat treatment (60 °C/60 min) among the EU import requirements for wood of Agrilus planipennis host plants. After a thorough analysis of the documents provided the Panel concluded that, with a low uncertainty, A. planipennis is likely to survive the proposed heat treatment of 60 °C/60 min, and that, to ensure a control level of 99 % the temperature of the heat treatment of 60 min should be higher than 70 °C. Following the publication of this scientific opinion, the US Authorities submitted a new proposal to the European Commission, consisting in a new heat treatment (71.1 °C/60 min). The EFSA Panel on Plant Health was asked to consider whether this new proposal was within the scope of the published opinion and, if not, to clarify its conclusion and indicate what data would be needed to assess the effectiveness of the new treatment. The Panel concluded that the new proposal is not within the scope of the opinion as the data provided by the US Authorities cannot be used to evaluate the effectiveness of the new proposed heat treatment. An accurate assessment of the new proposed heat treatment (71.1 °C/60 min) would require an experiment including several temperatures higher than 70 °C (one corresponding to the proposed treatment). Regarding the data requirements for assessing the effectiveness of the new treatment, the Panel lists the information required in the checklist presented in the Panel’s draft guidance document on methodology for evaluation of the effectiveness of options to reduce the risk of introduction and spread of organisms harmful to plant health in the EU territory, currently under public consultation on EFSA website. In 2011, the EFSA Panel on Plant Health was asked by the European Commission to provide an opinion on a technical file submitted by the US Authorities to support a request to list a new heat treatment (60 °C/60 min) among the EU import requirements for wood of Agrilus planipennis host plants. After a thorough analysis of the documents provided the Panel concluded that, with a low uncertainty, A. planipennis is likely to survive the proposed heat treatment of 60 °C/60 min, and that, to ensure a control level of 99 % the temperature of the heat treatment of 60 min should be higher than 70 °C. Following the publication of this scientific opinion, the US Authorities submitted a new proposal to the European Commission, consisting in a new heat treatment (71.1 °C/60 min). The EFSA Panel on Plant Health was asked to consider whether this new proposal was within the scope of the published opinion and, if not, to clarify its conclusion and indicate what data would be needed to assess the effectiveness of the new treatment. The Panel concluded that the new proposal is not within the scope of the opinion as the data provided by the US Authorities cannot be used to evaluate the effectiveness of the new proposed heat treatment. An accurate assessment of the new proposed heat treatment (71.1 °C/60 min) would require an experiment including several temperatures higher than 70 °C (one corresponding to the proposed treatment). Regarding the data requirements for assessing the effectiveness of the new treatment, the Panel lists the information required in the checklist presented in the Panel’s draft guidance document on methodology for evaluation of the effectiveness of options to reduce the risk of introduction and spread of organisms harmful to plant health in the EU territory, currently under public consultation on EFSA website.

Following a request by the European Commission, EFSA’s Panel on Plant Health was asked to deliver a statement to clarify the current scientific knowledge regarding the identity of the apple snails in the context of the evaluation of the pest risk analysis prepared by the Spanish Ministry of Environment and Rural and Marine Affairs (EFSA Panel on Plant Health (PLH), 2012). The Panel concludes on the risk to plant health posed by Pomacea species in the ‘canaliculata complex’, that out of the around 50 species in the genus of Pomacea, four species P. canaliculata, P. insularum, P. lineata and P. maculata belong to the ‘canaliculata complex’, where P. insularum and P. maculata are recently considered to be synonyms. Current methods of identification imply high uncertainty if risk reduction options are applied at the Pomacea single species level. The Spanish pest risk analysis identifies important plant health risks connected to Pomacea species. The available scientific evidence indicates that other Pomacea species may pose similar risks to plant health as identified for P. insularum. The Panel clarifies that risk reduction options should not be targeted to single species of the genus Pomacea considering: (i) the dynamical situation in the current study on the systematics of the Ampullariidae species and the genus Pomacea in particular; (ii) the uncertainties and the possible unexpected evolution of the invasive potential of species of Pomacea other than P. insularum and P. canaliculata; (iii) the poor knowledge on the trophic habits of many species of the genus Pomacea, with possible overlaps in the trophic niche (macrophytes); (iv) the high uncertainty on the identification of the different Pomacea species. Following a request by the European Commission, EFSA’s Panel on Plant Health was asked to deliver a statement to clarify the current scientific knowledge regarding the identity of the apple snails in the context of the evaluation of the pest risk analysis prepared by the Spanish Ministry of Environment and Rural and Marine Affairs (EFSA Panel on Plant Health (PLH), 2012). The Panel concludes on the risk to plant health posed by Pomacea species in the ‘canaliculata complex’, that out of the around 50 species in the genus of Pomacea, four species P. canaliculata, P. insularum, P. lineata and P. maculata belong to the ‘canaliculata complex’, where P. insularum and P. maculata are recently considered to be synonyms. Current methods of identification imply high uncertainty if risk reduction options are applied at the Pomacea single species level. The Spanish pest risk analysis identifies important plant health risks connected to Pomacea species. The available scientific evidence indicates that other Pomacea species may pose similar risks to plant health as identified for P. insularum. The Panel clarifies that risk reduction options should not be targeted to single species of the genus Pomacea considering: (i) the dynamical situation in the current study on the systematics of the Ampullariidae species and the genus Pomacea in particular; (ii) the uncertainties and the possible unexpected evolution of the invasive potential of species of Pomacea other than P. insularum and P. canaliculata; (iii) the poor knowledge on the trophic habits of many species of the genus Pomacea, with possible overlaps in the trophic niche (macrophytes); (iv) the high uncertainty on the identification of the different Pomacea species.

The Panel on Plant Health conducted a pest risk assessment for Tomato spotted wilt virus (TSWV) including the identification and evaluation of risk reduction options. The plants for planting pathway is considered the most important one and rated as likely, with medium uncertainty. TSWV, reported in many Member States, has one of the widest host range for plant viruses and has three widely distributed thrips vector species in the risk assessment area. For countries falling under the provisions of 2000/29/EC Annex IIAII legislation, the probability of establishment is rated as very likely, with low uncertainty. For Finland and Sweden, protected zone under the 2000/29/EC Annex IB legislation, the probability of establishment is rated unlikely to moderately likely. Spread can occur through the activity of thrips vectors and through trade of infected hosts. The probability of spread in Member States under Annex IIAII provisions is evaluated as likely, with low uncertainty. In Finland and Sweden, spread is rated as unlikely to moderately likely, with medium uncertainty. Since TSWV may cause both yield and quality losses in a wide range of hosts, a major impact is predictable in the absence of appropriate control measures, with medium uncertainty. The risk reduction options evaluated by the Panel are those addressing either the sanitary status of the propagation material (including the provisions of 2000/29/EC Annex IIAII and Annex IB, statutory certification system and the use of voluntary industry standards) or those addressing the control of TSWV epidemic development through actions directed at the virus or at its vectors (including cultural methods to reduce crop infestation and chemical or biological control of thrips vectors). Limitations of the current measures and the potential consequences of repealing the current legislation are discussed.

The European Commission requested the Panel on Plant Health to deliver a scientific opinion on the phytosanitary risk of plants (other than fruits and seeds) of Pinus pinea and of the genera Chamaecyparis, Cryptomeria and Juniperus for the spread of pine wood nematode (PWN) via movement of infested plants or untreated plant products or by supporting natural spread of PWN in conjunction with European species of the vector. The Panel analysed the data submitted by Portugal regarding surveys on the Tróia Peninsula where P. pinaster and P. pinea co-occur, and the related laboratory results of Naves et al. (2006) on feeding and oviposition preferences of Monochamus galloprovincialis. The Panel also undertook a comprehensive review of the literature. The zero infestation of PWN recorded on P. pinea on the Tróia Peninsula was not significantly different from the result for P. pinaster, because of the small P. pinea sample. Hence, the conclusion that P. pinea is not a host plant for PWN is not supported by the data submitted, principally because of low statistical confidence arising from the few P. pinea trees present. Moreover, the limited presence of P. pinea in the study areas means that the results are representative neither of the Tróia Peninsula nor of other parts of Portugal. Naves et al. (2006) recorded some oviposition by M. galloprovincialis on P. pinea, but less than on other hosts. No differences in feeding of M. galloprovincialis on P. pinaster and P. pinea were detected, thus potentially allowing PWN transmission to trees by this route. The available information regarding the genera Chamaecyparis, Cryptomeria and Juniperus as potential hosts of Monochamus spp. and PWN suggests overall a low susceptibility to PWN or its vectors; the uncertainty concerning PWN is high and would require supplementary research. The European Commission requested the Panel on Plant Health to deliver a scientific opinion on the phytosanitary risk of plants (other than fruits and seeds) of Pinus pinea and of the genera Chamaecyparis, Cryptomeria and Juniperus for the spread of pine wood nematode (PWN) via movement of infested plants or untreated plant products or by supporting natural spread of PWN in conjunction with European species of the vector. The Panel analysed the data submitted by Portugal regarding surveys on the Tróia Peninsula where P. pinaster and P. pinea co-occur, and the related laboratory results of Naves et al. (2006) on feeding and oviposition preferences of Monochamus galloprovincialis. The Panel also undertook a comprehensive review of the literature. The zero infestation of PWN recorded on P. pinea on the Tróia Peninsula was not significantly different from the result for P. pinaster, because of the small P. pinea sample. Hence, the conclusion that P. pinea is not a host plant for PWN is not supported by the data submitted, principally because of low statistical confidence arising from the few P. pinea trees present. Moreover, the limited presence of P. pinea in the study areas means that the results are representative neither of the Tróia Peninsula nor of other parts of Portugal. Naves et al. (2006) recorded some oviposition by M. galloprovincialis on P. pinea, but less than on other hosts. No differences in feeding of M. galloprovincialis on P. pinaster and P. pinea were detected, thus potentially allowing PWN transmission to trees by this route. The available information regarding the genera Chamaecyparis, Cryptomeria and Juniperus as potential hosts of Monochamus spp. and PWN suggests overall a low susceptibility to PWN or its vectors; the uncertainty concerning PWN is high and would require supplementary research.

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. Short-distance 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, long-distance 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. Possible improvements to current measures are described and uncertainties discussed.

The Panel considers the Spanish pest risk analysis (PRA) to be clear and to provide appropriate supporting evidence. However, (i) the environmental impact assessment is incomplete and (ii) the estimates for the potentially endangered area are too limited. The Panel points out that large areas of the European Union have climatic conditions, that are very similar to those of the areas of native distribution of Pomacea spp. snails, and suitable host plants are available. The Panel agrees with the Spanish PRA on the following points with regard to the risk assessment area: (i) the potential consequences of the organism for rice crops are major; (ii) the probability for establishment of the organism is very likely and (iii) the probability of spread is estimated as likely. The Panel disagrees with the Spanish PRA on the following points and considers (i) the effects on the environment to be massive under suitable environmental conditions in the PRA area and (ii) the probability of entry of the organism to be high. Regarding risk reduction options the Panel agrees with the Spanish PRA that no single risk reduction method is sufficient to halt the introduction and spread of Pomacea spp. snails in the PRA area. However, a legislative ban on import of Pomacea spp. is the only risk reduction option identified that can reduce the probability of entry. The many other risk reduction options listed will help to reduce the probability of spread within the PRA area. The Panel considers that the risk reduction options should target the canaliculata complex, as Pomacea insularum and P. canaliculata, as well as other species from the complex, are almost indistinguishable. This is of particular importance for risk reduction options addressing both breeding and trade of the organism. The Panel considers the Spanish pest risk analysis (PRA) to be clear and to provide appropriate supporting evidence. However, (i) the environmental impact assessment is incomplete and (ii) the estimates for the potentially endangered area are too limited. The Panel points out that large areas of the European Union have climatic conditions, that are very similar to those of the areas of native distribution of Pomacea spp. snails, and suitable host plants are available. The Panel agrees with the Spanish PRA on the following points with regard to the risk assessment area: (i) the potential consequences of the organism for rice crops are major; (ii) the probability for establishment of the organism is very likely and (iii) the probability of spread is estimated as likely. The Panel disagrees with the Spanish PRA on the following points and considers (i) the effects on the environment to be massive under suitable environmental conditions in the PRA area and (ii) the probability of entry of the organism to be high. Regarding risk reduction options the Panel agrees with the Spanish PRA that no single risk reduction method is sufficient to halt the introduction and spread of Pomacea spp. snails in the PRA area. However, a legislative ban on import of Pomacea spp. is the only risk reduction option identified that can reduce the probability of entry. The many other risk reduction options listed will help to reduce the probability of spread within the PRA area. The Panel considers that the risk reduction options should target the canaliculata complex, as Pomacea insularum and P. canaliculata, as well as other species from the complex, are almost indistinguishable. This is of particular importance for risk reduction options addressing both breeding and trade of the organism.

The European Commission requested EFSA’s Panel on Plant Health to perform the pest categorisation for the 24 viruses of the Tospovirus genus for the EU territory. The following tospoviruses were analysed: Tomato spotted wilt virus (TSWV), Impatiens necrotic spot virus (INSV), Iris yellow spot virus (IYSV), Polygonum ringspot virus (PolRSV), Groundnut ringspot virus (GRSV), Tomato chlorotic spot virus (TCSV), Alstroemeria necrotic streak virus (ANSV), Chrysanthemum stem necrosis virus (CSNV), Melon severe mosaic virus (MSMV), Tomato yellow (fruit) ring virus (TYRV), Tomato zonate spot virus (TZSV), Groundnut yellow spot virus (GYSV), Groundnut chlorotic fan-spot virus (GCFSV), Groundnut bud necrosis virus (GBNV), Zucchini lethal chlorosis virus (ZLCV), Capsicum chlorosis virus (CaCV), Watermelon bud necrosis virus (WBNV), Watermelon silver mottle virus (WSMoV), Tomato necrotic ringspot virus (TNRV), Calla lily chlorotic spot virus (CCSV), Melon yellow spot virus (MYSV), Soybean vein necrosis associated virus (SVNaV), Bean necrotic mosaic virus (BeNMV) and Pepper necrotic spot virus (PNSV). In reaching its conclusions, the Panel considered four parameters to be of critical importance in the risk assessment area: (i) the presence of a tospovirus, (ii) the existence of host plants, (iii) the existence of thrips vector species and (iv) the potential for damage to crops grown in Europe. Based on its analysis, the Panel concluded that the 24 viruses analysed could be allocated to four different risk groups. Seven viruses (GRSV, TCSV, ANSV, CSNV, MSMV, TYRV, TZSV) for which both thrips species vectors and natural or experimental hosts crops are present in the EU territory were considered by the Panel to represent the highest risk to the EU territory. In contrast, three viruses (INSV, IYSV and PolRSV) already present in the risk assessment area were not considered by the Panel to pose a risk justifying the development of full risk assessments.

The European Food Safety Authority (EFSA) requested the Panel on Plant Health to develop a methodology for assessing the environmental risks posed by harmful organisms that may enter, establish and spread in the European Union. To do so, the Panel first reviewed the methods for assessing the environmental risks of plant pests that have previously been used in pest risk assessment. The limitations identified by the review led the Panel to define the new methodology for environmental risk assessment which is described in this guidance document. The guidance is primarily addressed to the EFSA PLH Panel and has been conceived as an enhancement of the relevant parts of the “Guidance on a harmonised framework for pest risk assessment and the identification and evaluation of pest risk management options by EFSA”. Emphasizing the importance of assessing the consequences on both the structural (biodiversity) and the functional (ecosystem services) aspects of the environment, this new approach includes methods for assessing both aspects for the first time in a pest risk assessment scheme. A list of questions has been developed for the assessor to evaluate the consequences for structural biodiversity and for ecosystem services in the current area of invasion and in the risk assessment area. To ensure the consistency and transparency of the assessment, a rating system has also been developed based on a probabilistic approach with an evaluation of the degree of uncertainty. Finally, an overview of the available risk reduction options for pests in natural environments is presented, minimum data requirements are described, and a glossary to support the common understanding of the principles of this opinion is provided.

Following a request from the EU Commission, the EFSA PLH Panel conducted a scientific opinion on risk analysis and supporting documents provided by APHIS/USDA in support of the request to remove the Union's plant health import requirement that citrus fruit imported into the EU be sourced from groves where, since the beginning of the last cycle of vegetation no symptoms of citrus canker were observed, neither in their vicinities. The PHL Panel concluded that the transmission of Xanthomonas citri subsp. citri (Xcc) on asymptomatic citrus fruit was more likely when the fruit were collected from infested than from non-infested areas and groves. Symptomatic fruit carries more Xcc cells than asymptomatic fruit and the packinghouse disinfectant treatments do not achieve the eradication of Xcc. The application of management option 2 (i.e. ‘allow distribution of all types and varieties of commercially packed citrus fruit to all US States, subject to packinghouse treatment with APHIS-approved disinfectant. No packinghouse phytosanitary inspection is required’) selected by USDA will result in an increase in the Xcc load of citrus fruit consignments and in a subsequent increase in the probability of spread of citrus canker through the fruit pathway. Some data provided in the APHIS-USDA documents support that citrus fruit remain a conceptually possible pathway for transmitting and establishing citrus canker disease. The PLH Panel agrees that transmission of Xcc from infected fruit to a susceptible host is rare. But the withdrawal of the current EU requirement that citrus fruit imported into the EU be sourced from groves where no symptoms of citrus canker have been observed in the field of production and in its immediate vicinity since the beginning of the last cycle of vegetation, will increase the probability of introduction of Xcc into new areas.

The Panel on Plant Health was asked to deliver a scientific opinion on the Pest Risk Analysis on Phytophthora ramorum prepared by the FP6 project RAPRA, taking into account comments by Member States and additional information since RAPRA. P. ramorum is the oomycete causing sudden oak death in the USA and leaf and twig blight/dieback on a range of ornamental species in North America and Europe. Currently P. ramorum is not listed as a harmful organism in Council Directive 2000/29/EC, but the Commission adopted in 2002 provisional emergency measures to prevent introduction into and spread within the EU. Recent large-scale outbreaks in Japanese larch (Larix kaempferi) plantations in the UK and Ireland have worsened the potential consequences in the risk assessment area. However, the Panel concludes that the broad narrative in the RAPRA report stands and supports its conclusion that “There is a risk of further entry (of known or new lineages and/or mating types), establishment and […] impact”. It is advisable to avoid introductions of different lineages because of inherent phenotypic differences and the potential for sexual recombination. The Panel supports the management options proposed in the RAPRA report and adds further measures for consideration. Uncertainty remains over the extent to which the association between control measures and gradual reduction in the number of cases in nurseries is causal. The emergency measures have not prevented outbreaks occurring in the natural environment. The many other remaining uncertainties (fitness of progeny, hybridisation with other Phytophthora species, host range and epidemiological role of new hosts, early detection of new outbreaks, understanding of long-range dispersal, structure of plant trade networks, origin of the pathogen) call for further research on P. ramorum across Europe. Regulatory work should keep updated with research results on P. ramorum and further development of the Japanese larch outbreaks.

The EFSA Panel on Plant Health has delivered a pest risk assessment on the risk posed by Monilinia fructicola to the EU territory and has identified risk management options and evaluated their effectiveness in reducing the risk to plant health posed by this organism. The Panel has also analysed the effectiveness of the special requirements presently listed in Annex IV, Part A, Section I of Council Directive 2000/29/EC, in reducing the risk of introduction of this pest into the EU territory. The Panel concluded that the main pathways for entry into the EU territory are plant material for propagation purposes and fruit of host genera and that, with the exception of dried fruit, the probability of entry is very likely. The probability of establishment is also very likely due to the suitable environmental conditions and to the widespread presence of host species, susceptible for most of the year, on most of the risk assessment area. Cultural practices and control measures currently applied and competition with other Monilinia species cannot prevent the establishment of M. fructicola. The probability of spread is very likely because of the multiple ways of dispersal of the pest. The overall impact in the endangered area is estimated to be moderate. Neither additional cultural measures nor increased fungicide treatments would be needed to control of brown rot in the orchard after the introduction of M. fructicola. The EFSA Panel on Plant Health has delivered a pest risk assessment on the risk posed by Monilinia fructicola to the EU territory and has identified risk management options and evaluated their effectiveness in reducing the risk to plant health posed by this organism. The Panel has also analysed the effectiveness of the special requirements presently listed in Annex IV, Part A, Section I of Council Directive 2000/29/EC, in reducing the risk of introduction of this pest into the EU territory. The Panel concluded that the main pathways for entry into the EU territory are plant material for propagation purposes and fruit of host genera and that, with the exception of dried fruit, the probability of entry is very likely. The probability of establishment is also very likely due to the suitable environmental conditions and to the widespread presence of host species, susceptible for most of the year, on most of the risk assessment area. Cultural practices and control measures currently applied and competition with other Monilinia species cannot prevent the establishment of M. fructicola. The probability of spread is very likely because of the multiple ways of dispersal of the pest. The overall impact in the endangered area is estimated to be moderate. Neither additional cultural measures nor increased fungicide treatments would be needed to control of brown rot in the orchard after the introduction of M. fructicola.

This document presents the scientific opinion of the Panel on Plant Health on the technical file submitted by the US Authorities to support a request to list a new option among the EU import requirements for wood of Agrilus planipennis host plants. The option under consideration is a heat treatment at 60 °C for 60 min to eliminate possible infestations of the wood by the emerald ash borer (EAB). The experiments leading the US Authorities to propose this option are presented in a scientific peer reviewed publication, Myers et al. (2009). The analysis of the aggregated data published by Myers et al. (2009) and based on a Probit regression model showed that the proposed treatment cannot guarantee a control level of 99 % or higher. The analysis of the individual data either from the original measurements or from a corrected dataset, using a Probit regression model, showed that it is likely to observe one live EAB out of an infestation of 100 after the proposed heat treatment of 60 °C/60 min. To ensure a control level of 99 % the temperature of the heat treatment of 60 min should be higher than 70 °C. Results obtained with a Poisson log linear model based on individual data showed that the estimated probability that one insect or more per m 2 survive the proposed heat treatment was higher than 0.6 and that there is a 0.1 probability that three insects or more per m 2 survive the proposed heat treatment. Based on these results, the Panel concludes that A. planipennis is likely to survive the proposed heat treatment of 60 °C/60 min with a low uncertainty, and that the alternative option proposed in the technical file submitted by the US Authorities for wood does not guarantee the wood to be free of A. planipennis. © European Food Safety Authority, 2011

Following a request from the European Commission, the EFSA Panel on Plant Health was asked to deliver a scientific opinion on a technical file submitted by the Japanese Authorities to support a derogation request from the EU import requirements for bonsai and topiary trees that are host plants of Anoplophora chinensis (Forster) (Coleoptera: Cerambycidae). Three options were proposed as alternatives to the existing requirements of the European Union: a) to reduce the required period to grow plants in field cages from two years to one season prior to export (from April to October); b) to allow grafting of scions with no risk of infestation by A. chinensis during the two years of field-cage cultivation and c) to remove the net from the field cage during the winter period (from November to March) when adult A. chinensis do not visit the area or lay eggs. The Panel evaluated the technical file and concluded that as the life cycle duration of the pest can be more than one season and larvae cannot be reliably detected within the plant, a reduction of the required growing period under complete physical protection increases the risk of entry into the EU compared with the current EU requirements. The Panel considered scions collected from a branch of a stock tree 50 cm or higher above the ground, with a diameter not exceeding 5 mm and a length of 5 cm, are unlikely to increase the risk of entry. The Panel also considered that, due to uncertainty on the occurrence of beetle flight and potential for oviposition between November and March, opening cages during this period may lead to an increased risk of entry into the EU compared to current measures. Following a request from the EU Commission, the EFSA PLH Panel conducted a scientific opinion on risk analysis and supporting documents provided by APHIS/USDA in support of the request to remove the Union's plant health import requirement that citrus fruit imported into the EU be sourced from groves where, since the beginning of the last cycle of vegetation no symptoms of citrus canker were observed, neither in their vicinities. The PHL Panel concluded that the transmission of Xanthomonas citri subsp. citri (Xcc) on asymptomatic citrus fruit was more likely when the fruit were collected from infested than from non-infested areas and groves. Symptomatic fruit carries more Xcc cells than asymptomatic fruit and the packinghouse disinfectant treatments do not achieve the eradication of Xcc. The application of management option 2 (i.e. ‘allow distribution of all types and varieties of commercially packed citrus fruit to all US States, subject to packinghouse treatment with APHIS-approved disinfectant. No packinghouse phytosanitary inspection is required’) selected by USDA will result in an increase in the Xcc load of citrus fruit consignments and in a subsequent increase in the probability of spread of citrus canker through the fruit pathway. Some data provided in the APHIS-USDA documents support that citrus fruit remain a conceptually possible pathway for transmitting and establishing citrus canker disease. The PLH Panel agrees that transmission of Xcc from infected fruit to a susceptible host is rare. But the withdrawal of the current EU requirement that citrus fruit imported into the EU be sourced from groves where no symptoms of citrus canker have been observed in the field of production and in its immediate vicinity since the beginning of the last cycle of vegetation, will increase the probability of introduction of Xcc into new areas.

The Panel on Plant Health was requested by the European Commission to deliver a scientific opinion on the risk posed by the oriental chestnut gall wasp, Dryocosmus kuriphilus to the EU territory and to identify and evaluate risk management options. Additional analyses were conducted by the Panel to a) determine the distribution of the endangered area within the EU territory; b) investigate the pattern and rate of pest diffusion and c) consider the environmental risk of introduction of the biological control agent Torymus sinensis identified as a potential management option. The Panel concluded in its assessment that a) Castanea plants for intended planting represent the main pathway for entry of D. kuriphilus to the EU; b) D. kuriphilus has a very high potential for establishment in the EU and the climate is suitable wherever Castanea sativa is grown in southern, central and western Europe; c) the average rate of spread of D. kuriphilus is estimated as 8 km/yr; d) spread within the EU is likely, due to adult dispersal by flight and the movement of plants containing eggs and larvae which remain undetected within dormant buds; e) the potential effects on fruit yield reduction are considered moderate and the environmental impact in Castanea woodland is considered as low; f) all EU chestnut production is endangered but the areas of fruit production with the highest degree day accumulations where D. kuriphilus is absent, e.g. in northern Portugal, northern Spain and south-west France, are identified as particularly at risk; g) management options to reduce likelihood of introduction and spread consist of certifying Castanea planting material from pest free areas/places of production; h) classical biological control and plant varietal resistance are identified as management options to reduce the magnitude of impact. The Panel on Plant Health was requested by the European Commission to deliver a scientific opinion on the risk posed by the oriental chestnut gall wasp, Dryocosmus kuriphilus to the EU territory and to identify and evaluate risk management options. Additional analyses were conducted by the Panel to a) determine the distribution of the endangered area within the EU territory; b) investigate the pattern and rate of pest diffusion and c) consider the environmental risk of introduction of the biological control agent Torymus sinensis identified as a potential management option. The Panel concluded in its assessment that a) Castanea plants for intended planting represent the main pathway for entry of D. kuriphilus to the EU; b) D. kuriphilus has a very high potential for establishment in the EU and the climate is suitable wherever Castanea sativa is grown in southern, central and western Europe; c) the average rate of spread of D. kuriphilus is estimated as 8 km/yr; d) spread within the EU is likely, due to adult dispersal by flight and the movement of plants containing eggs and larvae which remain undetected within dormant buds; e) the potential effects on fruit yield reduction are considered moderate and the environmental impact in Castanea woodland is considered as low; f) all EU chestnut production is endangered but the areas of fruit production with the highest degree day accumulations where D. kuriphilus is absent, e.g. in northern Portugal, northern Spain and south-west France, are identified as particularly at risk; g) management options to reduce likelihood of introduction and spread consist of certifying Castanea planting material from pest free areas/places of production; h) classical biological control and plant varietal resistance are identified as management options to reduce the magnitude of impact.