Prima phacie1: a new European Food Safety Authority funded research project taking a comparative approach to pest risk assessment and methods to evaluate pest risk management options

In late 2009, a European Food Safety Authority (EFSA)‐funded project (Prima phacie) began work to review and test methodologies for conducting pest risk assessment by means of case studies on three phytoplasmas (Candidatus Phytoplasma mali, Ca. P. prunorum, Ca. P. pyri); two bacteria (Acidovorax avenae subsp. citrulli, Xanthomonas citri [=X. axonopodis] pv. citri); two fungi (Guignardia citricarpa, Mycosphaerella dearnessii); two nematodes (Meloidogyne chitwoodi, M. fallax); and an insect (Anoplophora glabripennis). Multiple risk assessment schemes and methods will be applied to each of the case study pests, allowing for a comparative assessment of methods. Methods to assess the effectiveness of possible risk management options for each pest will also be evaluated. The project will further develop the scientific basis for pest risk assessment within the European Community and identify methodologies most suitable for conducting risk assessments and for evaluating the effectiveness of possible risk management options by the EFSA Panel on Plant Health in order to support European decision making. The project lasts 29 months, and is being conducted by an international consortium of 11 partners consisting of phytosanitary organizations, research institutes and a university. Results will be disseminated via conventional publications and at a workshop in March 2012.     

The EFSA assessment of Trichilogaster acaciaelongifoliae as biocontrol agent of the invasive alien plant Acacia longifolia: a new area of activity for the EFSA Plant Health Panel?

This paper summarizes the first assessment by the European Food Safety Authority (EFSA) Plant Health (PLH) Panel of a biological control agent (BCA) of an invasive plant. This followed a request by the European Union (EU) Commission to assess the risk to plant health in the EU of an intentional release of the bud‐galling wasp Trichilogaster acaciaelongifoliae for the control of Acacia longifolia. The EFSA PLH Panel also published a statement on the process of assessing the risk of the intentional releases of BCAs of invasive alien plants. Trichilogaster acaciaelongifoliae feeds on A. longifolia and Acacia floribunda. Acacia longifolia is an invasive alien plant species that has a negative effect on biodiversity and ecosystems in Portugal, whereas A. floribunda is not invasive in the EU. Both species are cultivated as ornamental plants in some EU countries. Climatic conditions in the EU are suitable for establishment of T. acaciaelongifoliae where host species are present. This BCA is moderately likely to spread in the EU by natural means, but could be intentionally moved to control A. longifolia in other locations. Its potential effects on invasive A. longifolia and on the cultivated ornamentals were assessed. The EFSA PLH Panel has shown with this work how such advice could be provided in the European Union.     

Pest risk analysis for Solanum elaeagnifolium and international management measures proposed

Solanum elaeagnifolium Cav., originating from the Americas, has been unintentionally introduced in all the other continents as a contaminant of commodities, and is considered one of the most invasive plants worldwide. In the Euro‐Mediterranean area, it is a huge threat in North African countries. It is also present in European Mediterranean countries (France, Greece, Italy and Spain), but still has a limited distribution. Through a logical sequence of questions, pest risk analysis (PRA) assessed the probability of S. elaeagnifolium entering, establishing, spreading and having negative impacts in European and Mediterranean countries. As this assessment revealed that the entry of the pest would result in an unacceptable risk, pest risk management options were selected to prevent the introduction of the plant. Preventive measures on plants or plant products traded internationally may directly or indirectly affect international trade. According to international treaties, PRA is a technical justification of such international preventive measures.     

Tools for visualizing and integrating pest risk assessment ratings and uncertainties*

The application of pest risk analysis (PRA) decision‐support schemes, such as that used by the European and Mediterranean Plant Protection Organization (EPPO), generates many ratings for likelihood or magnitude of risk factors, each with an associated uncertainty. In accordance with the international standard ISPM 11 ( FAO, 2004 ), questions have been devised to assess the key elements of pest risk in the four main sections of pest risk assessment: Entry, Establishment, Spread and Impact. After completing each section, risk assessors are required to give a summary rating and an uncertainty score for that section. The large number of question ratings and uncertainty scores make the task of summarizing each section and its uncertainty quite difficult. Two graphical tools have been developed to aid this task: the PRA Risk score and uncertainty visualizer (Visualizer) and the Rule‐based matrix model (RBMM). The Visualizer presents a case summary graph on a single page in such a way that the risk assessors and peer reviewers can see rating scores and uncertainties in a pictorial manner; the RBMM integrates all the individual questions in the assessment through a hierarchy of rules that attempt to mimic the logic used by the assessors and are arranged in the form of a flow chart to give an overall rating with an accompanying expression of uncertainty.     

Beyond compliance: project on an integrated systems approach for pest risk management in South East Asia

The Beyond Compliance project, which began in July 2011 with funding from the Standards and Trade Development Facility for 2 years, aims to enhance competency and confidence in the South East Asian sub‐region by applying a Systems Approach for pest risk management. The Systems Approach involves the use of integrated measures, at least two of which are independent, that cumulatively reduce the risk of introducing exotic pests through trade. Although useful in circumstances where single measures are inappropriate or unavailable, the Systems Approach is inherently more complicated than single‐measure approaches, which may inhibit its uptake. The project methodology is to take prototype decision‐support tools, such as Control Point‐Bayesian Networks (CP‐BN), developed in recent plant health initiatives in other regions, including the European PRATIQUE project, and to refine them within this sub‐regional context. Case studies of high‐priority potential agricultural trade will be conducted by National Plant Protection Organizations of participating South East Asian countries in trials of the tools, before further modifications. Longer term outcomes may include: more robust pest risk management in the region (for exports and imports); greater inclusion of stakeholders in development of pest risk management plans; increased confidence in trade negotiations; and new opportunities for trade.     

Towards a tiered test strategy for plant protection products to address mixture toxicity by alternative approaches in human health assessment

Plant protection products (PPPs) consist of pesticide active substances and co‐formulants. Generally, active substance effects are assumed to dominate in PPP toxicity. Nevertheless, co‐formulants may well affect the toxicity of PPPs via toxicodynamic and toxicokinetic interaction. To account for potential mixture effects and improve PPP data requirements for application in risk assessment, a tiered test strategy is proposed. The strategy is based on a comparison of PPP and active substance toxicity, which enables the prioritisation of PPPs for further testing, adaptation of the toxicological threshold value or removal of toxic co‐formulants from the PPP. Moreover, it focuses on the integrative assessment of existing information and newly generated data using alternative test methods. The proposed strategy will improve PPP toxicological assessment by accounting for mixture toxicity, providing a set of regulatory options for risk assessment and the necessary data for hazard assessment. The predictivity of alternative methods for PPPs will improve by evaluation of their reliability and uncertainty. © 2020 The Authors. Pest Management Science published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.     

Common vole (Microtus arvalis) ecology and management: implications for risk assessment of plant protection products

Common voles (Microtus arvalis) are common small mammals in some European landscapes. They can be a major rodent pest in European agriculture and they are also a representative generic focal small herbivorous mammal species used in risk assessment for plant protection products. In this paper, common vole population dynamics, habitat and food preferences, pest potential and use of the common vole as a model small wild mammal species in the risk assessment process are reviewed. Common voles are a component of agroecosystems in many parts of Europe, inhabiting agricultural areas (secondary habitats) when the carrying capacity of primary grassland habitats is exceeded. Colonisation of secondary habitats occurs during multiannual outbreaks, when population sizes can exceed 1000 individuals ha^?1. In such cases, in‐crop common vole population control management has been practised to avoid significant crop damage. The species' status as a crop pest, high fecundity, resilience to disturbance and intermittent colonisation of crop habitats are important characteristics that should be reflected in risk assessment. Based on the information provided in the scientific literature, it seems justified to modify elements of the current risk assessment scheme for plant protection products, including the use of realistic food intake rates, reduced assessment factors or the use of alternativee focal rodent species in particular European regions. Some of these adjustments are already being applied in some EU member states. Therefore, it seems reasonable consistently to apply such pragmatic and realistic approaches in risk assessments for plant protection products across the EU. © 2013 Society of Chemical Industry     

PM 7/29 (3) Tilletia indica

Specific scope

This Standard describes a diagnostic protocol for Tilletia indica. 1 It should be used in conjunction with PM 7/76 Use of EPPO diagnostic protocols.

Specific approval and amendment

This Standard was originally developed under the EU DIAGPRO Project (SMT 4‐CT98‐2252) by a partnership of contractor laboratories and interlaboratory comparison in European countries. First approved as an EPPO Standard in 2003–09. First revision approved in 2007–09. Second revision approved on 2017–11. Although this EPPO Diagnostic Standard differs in terms of format it is in general consistent with the content of the IPPC Standard adopted in 2014 on Tilletia indica (Annex 4 to 2006 ) with the following exceptions. (1) In the EPPO region, as the pest is not present, a higher confidence in the results is required, a sieve wash test should be carried out (optional in the IPPC protocol). (2) When fewer than 10 teliospores are found the options should allow testing the (<10) teliospores with conventional or real‐time PCR (this was not an option in the IPPC protocol flow chart, although it was stated that direct real‐time PCR could be used on individual teliospores in the text). (3) The method for extracting teliospores from untreated seed or grain by size‐selective sieving is slightly different based on the experience in the region (European Union test performance study). The EPPO Diagnostic Standard also includes a test for a direct real‐time PCR for use on pellets (developed in 2016). Some additional information on methods for morphological identification, from the former version of the EPPO Standard, which are not in the IPPC protocol are included in this protocol in Appendix 3 as they were considered useful by the members of the Panel on Diagnostics in Mycology.     

Detection and identification of Xanthomonas arboricola pv. pruni from symptomless plant material: results of an Italian test performance study

Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot disease of stone fruits, is a regulated quarantine pathogen in the European Union, listed as an A2 pest by the European and Mediterranean Plant Protection Organization (EPPO). Because detection and identification of this pathogen is key for its management and to ensure the production of pest free propagation material, it should be based on reliable tests, in particular when dealing with symptomless material. The current EPPO diagnostic Standard (PM 7/64) does not provide specific molecular methods for detection of this pest. The present paper summarizes the results of a test‐performance study (TPS) to validate, at a national level, a detection procedure for this bacterium. A working group was established in order to evaluate the performance criteria for tests included in the current EPPO Standard, and for a conventional PCR. On the basis of the obtained performance criteria, a diagnostic procedure was elaborated and then applied to perform an inter‐laboratory comparison. Screening tests for the detection of the bacterium on symptomless plant material based on IF and/or PCR were proposed, in parallel with isolation on agar media. For identification two methods were suggested: a molecular test or IF. This paper reports on the results of the TPS and proposes a flow diagram for the detection and identification of X. arboricola pv. pruni.     

Risk maps for targeting exotic plant pest detection programs in the United States

In the United States, pest risk maps are used by the Cooperative Agricultural Pest Survey for spatial and temporal targeting of exotic plant pest detection programs. Methods are described to create standardized host distribution, climate and pathway risk maps for the top nationally ranked exotic pest targets. Two examples are provided to illustrate the risk mapping process: late wilt of corn (Harpophora maydis) and the giant African land snail (Achatina fulica). Host risk maps were made from county‐level crop census and USDA Forest Inventory and Analysis data, respectively. Climate risk maps were made using the North Carolina State University–USDA APHIS Plant Pest Forecasting System (NAPPFAST), which uses a web‐based graphical user interface to link climatic and geographic databases with interactive templates for biological modelling. Pathway risk maps were made using freight flow allocation data sets to move commodities from 7 world regions to 3162 US urban areas. A new aggregation technique based on the Pareto dominance principle was used to integrate maps of host abundance, climate and pathway risks into a single decision support product. The maps are publicly available online ( http://www.nappfast.org ). Key recommendations to improve the risk maps and their delivery systems are discussed.     

Plant pest risk information system (PPRIS) for USDA-APHIS: design of a functional prototype

The Plant Pest Risk Information System (PPRIS) is a computerized decision-support system for plant pest risk assessment in the USA, being developed for use by personnel of the US Department of Agriculture's (USDA) Plant Protection and Quarantine, Animal and Plant Health Inspection Service (APHIS). PPRIS is being designed to retrieve information from such diverse sources as: EPPO PQ database, USDA-Agricultural Research Service's (ARS) Fungi on Plants and Plant Products database, bibliographic databases on compact disc media, on-line INTERNET databases and risk assessment documents. PPRIS will offer access to a wide variety of risk assessment processes. A PPRIS evaluation prototype was created in Visual Basic ver. 3.0 operating in a Windows 3.1 environment. EPPO-PQ and ARS-Fungi databases were imported and stored in ORACLE ver. 6.0. Query functionality of the prototype was tested by retrieving information from the two internal ORACLE databases. The PPRIS evaluation prototype provides interfaces to the CABPEST bibliographic compact disc and to communication software for on-line database searches. Three risk assessment processes were incorporated into the evaluation prototype: the decision sheet, generic risk assessment and enhanced hazard identification. The evaluation prototype also includes access to Wordperfect for Windows through the Windows Program Manager for storage and retrieval of risk assessment documents.     

Invasive alien plants in plant health: a review of the past ten years

The International Plant Protection Convention (IPPC) provides the background for National Plant Protection Organisations (NPPOs) to regulate and control invasive alien species that are harmful to plants. This subject was specifically discussed for the first time 10 years ago at IPPC level, and further explored by an IPPC open‐ended working group. The resulting concept was considered at EU level, and the EU Council supported the suitability of the plant health framework for these species, requesting the EU Commission to further analyse the needs for regulatory work in the EU plant health regime. Subsequently the European and Mediterranean Plant Protection Organization (EPPO) started a new working programme. The international conference ‘Invasive alien species and the IPPC’ set a signal for IPPC contracting parties to encourage their NPPOs to enforce actions on invasive alien species. IPPC standards on pest risk analysis (PRA) were adapted so as to include invasive alien species harmful to plants, and a memorandum of cooperation was adopted between the Secretariats of the IPPC and the Convention on Biological Diversity (CBD). At present, the EU Commission, DG Environment is developing a European strategy on invasive alien species. The EU Plant Health Regulatory System is currently subjected to a major evaluation process in which a clearer inclusion of invasive alien species into the system is one of the strategic discussions.     

Internal methods comparison study and inter‐laboratory study on Clavibacter michiganensis subsp. michiganensis in tomato seeds1

Bacterial canker of tomato is a disease caused by Clavibacter michiganensis subsp. michiganensis, a quarantine bacterium, the spread of which has not been completely controlled in spite of the phytosanitary measures taken within the EPPO region. Since 2008 the French National Laboratory for Plant Health (LNPV) has been working on the assessment of the methods used in laboratories to detect the presence of Clavibacter michiganensis subsp. michiganensis in tomato seeds i.e. dilution plating on semi‐selective media and immunofluorescence. In the 1st stage of the assessment, a methods comparison study was performed with reference strains to determine the performance criteria of the tests in optimal conditions. In the 2nd stage, an inter‐laboratory study on naturally and artificially contaminated seeds was performed with 8 laboratories from 6 European countries. This study demonstrated the strengths and weaknesses of the tests currently in use. Two laboratories took the opportunity the collaborative study offered to evaluate alternative tests: BIO‐PCR and IMS‐plating. These could offer interesting alternatives to optimise the detection procedure for Clavibacter michiganensis subsp. michiganensis on tomato seeds.     

Towards a more reasoned assessment of the threat to wheat crops from <Emphasis Type="Italic">Tilletia indica</Emphasis>, the cause of Karnal bunt disease

The interpretation of information used to defend an assessment that T. indica, the cause of Karnal bunt of wheat, has a high risk of establishing in Europe and of causing significant yield/quality losses is questioned. Karnal bunt has only established in locations that are arid or semi-arid with hot summers and cool/mild winters. There is very strong circumstantial evidence that substantial amounts of seed contaminated with teliospores of T. indica were sown in Europe in the past without the appearance of Karnal bunt. It is unlikely that sufficient numbers of teliospores would survive long enough on the soil surface under European conditions and then synchronise germination during the period at heading when wheat is vulnerable to infection to guarantee disease expression. Karnal bunt is regarded as a minor disease everywhere it occurs. Almost two thirds of European wheat cultivars inoculated by a severe boot injection method have been categorised as either resistant or highly resistant to T. indica. Yield/quality losses would be expected to be low even if the pathogen were capable of establishing in Europe. The status of T. indica as an important quarantine pest is based on the indirect economic consequences of the appearance of the pathogen and not on the direct damage it causes to wheat crops. Arguments in this and previous reviews advocating a more reasoned and comprehensive assessment of the threat to Europe, North America and other locations from T. indica need to be taken into consideration in any new pest risk analyses. David Jones is a retired employee of the Central Science Laboratory (CSL). Statements and opinions expressed in this paper are those of the author and are not the views of CSL.     

The western corn rootworm,a new threat to European agriculture: opportunities for biotechnology?

BACKGROUND: During the early 1990s, the western corn rootworm, Diabrotica virgifera virgifera Le Conte (WCR), a maize pest, invaded the European continent. The continuous spread of the pest has introduced a new constraint into European maize production. As the damage caused by the invasive species is highly variable and different crop protection (CP) strategies are available, farmers' optimal strategies are not obvious. This study uses a simulation model to assess the competitiveness of different CP strategies in seven Central European countries. RESULTS: Results indicate a high degree of heterogeneity in the profitability of different CP strategies, depending on the production parameters in each country. In general, crop rotation and Bt maize offer the best solutions to farmers, but, in continuous (non‐rotated) maize cultivation, chemical CP options may capture part of the market. For Austrian continuous maize production it is found that not deregulating Bt maize implies that farmers forego revenues of up to €59 ha^?1. CONCLUSIONS: In the presence of WCR, producing maize by an economically sound method requires incorporating country‐ and farm‐specific characteristics into the decision framework. Also, not deregulating Bt maize has direct monetary consequences for many farmers that could influence total maize output and resistance management. Copyright © 2010 Society of Chemical Industry     

Potential spread of kiwifruit bacterial canker (Pseudomonas syringae pv. actinidiae) in Europe

Pest risk analyses (PRAs) are conducted to determine whether an organism is a pest and whether and how it should be regulated. Estimation of the potential area of establishment and pest spread are key factors of this analysis. Tools for modelling and mapping of these key factors have to be quick and easily applicable for a wide variety of organisms with limited data for parameterization. For this purpose, a dispersal kernel model based on a 2Dt‐distribution had been developed in a European Union project (PRATIQUE). The aim of the present study was the evaluation of this spread model hitherto tested on insects, plants, fungi and nematodes in order to determine its applicability to bacterial pests. Therefore, the potential distribution and spread of kiwifruit bacterial canker Pseudomonas syringae pv. actinidiae in Europe was investigated based on climatic suitability and host plant availability. The results of the modelling were compared with the spread history of the pest in Europe. It is shown that this generic spread model can also be applied to a bacterial pest.     

(Q)SAR tools for the prediction of mutagenic properties: Are they ready for application in pesticide regulation?

The assessment of human health risks resulting from the presence of metabolites in groundwater and food residues has become an important element in pesticide authorisation. In this context, the evaluation of mutagenicity is of particular interest and a paradigm shift from exposure‐triggered testing to in silico‐based screening has been recommended in the European Food Safety Authority (EFSA) Guidance on the establishment of the residue definition for dietary risk assessment. In addition, it is proposed to apply in silico predictions when experimental mutagenicity testing is not possible due to a lack of sufficient quantities of the pesticide metabolite. This, combined with animal welfare and economic considerations, has led to a situation where an increasing number of in silico studies are submitted to regulatory authorities. Whilst there is extensive experience with in silico predictions for mutagenicity in the chemical and pharmaceutical industry, their suitability in pesticide regulation is still insufficiently considered. Therefore, we herein discuss critical issues that need to be resolved to successfully implement (Quantitative) Structure‐Activity Relationship ((Q)SAR) as an accepted tool in pesticide regulation. For illustration purposes, the results of a pilot study are included. The presented study highlights a need for further improvement regarding the predictivity and applicability domain of (Q)SAR systems for pesticides and their metabolites, but also raises other questions such as model selection, establishment of acceptance criteria, harmonised approaches to the combination of model outputs into overall conclusions, adequate reporting and data sharing. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

A quantitative model for trade pathway analysis of plant pest entry and transfer to a host in European Union territory

A quantitative pathway model, QPAFood, has been designed to support risk assessment for plant pest entry into European Union (EU) territory on a range of edible plant commodities via trade flows. The model calculates the distribution of an imported infested/infected commodity along a pathway into and within the EU from source countries, based on Eurostat data and other data/information. The model determines the implications of global trade pathways for the potential arrival of the infested commodity in the EU28 Member States. Within each Member State, the calculation proceeds by distributing the commodity according to uses, notably retail or processing, to the vulnerable area of commercial host crops determined in each NUTS2 region and then quantifies the consequent potential for pest–host contact which could lead to pest transfer. Annual and monthly estimates of contact risk are tabulated and visualized for Member States and NUTS2 regions. The model was developed originally for the European Food Safety Authority using four case studies of specific pest–commodity combinations. These pests had relatively limited host ranges and the model has now been extended in the context of the EC FP7 DROPSA project for the multiple commodity pathways associated with the highly polyphagous fruit pest Drosophila suzukii.     

Risikoanalyse von gebietsfremden Pflanzen—Das neue Konzept der EPPO

The European and Mediterranean Plant Protection Organisation (EPPO) aims to prevent the entry and spread of organisms harmful to both cultivated and wild plants. Basing their activities on those of the Convention on Biological Diversity and the International Plant Protection Convention, the EPPO is developing a new concept for invasive alien species and ‘plants as pests’. A pest risk analysis is necessary in most cases to identify which organisms should be regulated and how. In accordance with the International Plant Protection Convention, an EPPO risk assessment standard exists for this purpose which has now been revised to be applicable also to potentially invasive alien plants and assess the effects they pose to the uncultivated environment. In 2003, the EPPO sent a questionnaire to its 44 member states asking for plants which have been intentionally or unintentionally introduced and are considered invasive. The member countries reported hundreds of species, of which 42 were selected for further assessment. This may result in recommendations for regulations and measures against the introduction and spread of all or some of these plants.     

Pyrethroid resistance and thiacloprid baseline susceptibility of European populations of Meligethes aeneus (Coleoptera: Nitidulidae) collected in winter oilseed rape

BACKGROUND: Pollen beetle, Meligethes aeneus F. (Coleoptera: Nitidulidae), is a major pest in European winter oilseed rape. Recently, control failures with pyrethroid insecticides commonly used to control this pest have been reported in many European countries. For resistance management purposes, the neonicotinoid insecticide thiacloprid was widely introduced as a new mode of action for pollen beetle control. RESULTS: A number of pollen beetle populations collected in Germany, France, Austria, Great Britain, Sweden, Denmark, Finland, Poland, Czech Republic and Ukraine were tested for pyrethroid resistance using lambda‐cyhalothrin‐coated glass vials (adult vial test). Most of the populations tested exhibited substantial levels of resistance to lambda‐cyhalothrin, and resistance ratios ranged from < 10 to > 2000. A similar resistance monitoring bioassay for the neonicotinoid insecticide thiacloprid was developed and validated by assessing baseline susceptibility data for 88 European pollen beetle populations. A variation of less than fivefold in response to thiacloprid was detected. The thiacloprid adult vial bioassay is based on glass vials coated with an oil‐dispersion‐based formulation of thiacloprid, resulting in a much better bioavailability compared with technical material. Analytical measurements revealed a > 56 and 28 day stability of thiacloprid and lambda‐cyhalothrin in coated glass vials at room temperature, respectively. No cross‐resistance between thiacloprid and lambda‐cyhalothrin based on log‐dose probit–mortality data was detected. CONCLUSION: Pyrethroid resistance in many European populations of M. aeneus was confirmed, whereas all populations are susceptible to thiacloprid when tested in a newly designed and validated monitoring bioassay based on glass vials coated with oil‐dispersion‐formulated thiacloprid. Based on the homogeneous results, it is concluded that thiacloprid could be an important chemical tool for pollen beetle resistance management strategies in European winter oilseed rape. Copyright © 2011 Society of Chemical Industry