Publications by authors named "Werf W"

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of the species complex (RSSC), a distinguishable cosmopolitan group of bacterial plant pathogens (including , and two subspecies of ) of the family Burkholderiaceae. The RSSC causes bacterial wilt in solanaceous crops, such as potato, tomato and pepper, but can also cause wilts in other important food crops such as fruit banana, plantain banana and cassava. The pest survives in the soil, and a number of weed species can also be infected by the pest, often asymptomatically.

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Pest categorisation of and .

EFSA J

January 2019

The Panel on Plant Health performed a pest categorisation of and , two well-defined insect species in the family Curculionidae, subfamily Scolytinae (Insecta: Coleoptera). They can be identified using taxonomic keys. is present in parts of Canada and the USA, and is present in parts of the USA, Guatemala, Honduras and Mexico.

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Pest categorisation of .

EFSA J

December 2018

The EFSA Panel on Plant Health (PLH) performed a pest categorisation of , (Lepidoptera: Tortricidae), the Manchurian fruit moth, for the territory of the EU. is a well-defined species that is recognised as a major pest of spp. in Far East Russia, Eastern Siberia and northern China.

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Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of spp. (non-EU), a well-defined and distinguishable group of fungal plant pathogens of the family Pucciniaceae affecting woody species. Many different species are recognised, of which at least 14 species are considered not to be native in the European Union.

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Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of spp. (non-EU), a well-defined and distinguishable group of fungal pathogens of the family Cronartiaceae. There are at least 40 species described within the genus, of which two are considered native to the EU ( and ) and one has been introduced in the 19th century () and is now widespread in the EU - these three species are thus not part of this pest categorisation.

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Pest categorisation of .

EFSA J

December 2018

The European Commission requested EFSA to conduct a pest categorisation of (Lepidoptera: Tortricidae), an oligophagous moth whose larvae feed mostly on leaves and fruit of different Rosaceae including cultivated apples, plums, cherries and pecans. It overwinters in soil and bark crevices of its host plants. has reliable identification methods, both for adults and immature stages.

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Pest categorisation of .

EFSA J

December 2018

The Panel on Plant Health performed a pest categorisation of , the causal agent of blotch of apple, for the EU. The pest is a well-defined fungal species and methods are available for its detection and identification. is present in Canada and the continental states of the USA.

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Pest categorisation of .

EFSA J

December 2018

The EFSA Panel on Plant Health performed a pest categorisation of the peach fruit moth, Matsumura (Lepidoptera: Carposinidae) for the EU. is not currently regulated in the EU although a valid species of no economic significance that was previously mistakenly synonymised with is regulated in Annex IIAI of 2000/29 EC. is a well-defined species that is recognised as a major pest of apples, peaches and pears in eastern China, Japan, Korea and Far East Russia.

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Pest categorisation of .

EFSA J

December 2018

The Panel on Plant Health performed a pest categorisation of , the causal agent of annular leaf spot of potato, for the EU. The pest is a well-defined fungal species and reliable methods exist for its detection and identification. is present in Bolivia, Ecuador, Peru and Venezuela.

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A conceptual framework was developed by a working group of the Scientific Committee of the European Food Safety Authority (EFSA) to guide risk assessors and risk managers on when and how to integrate ecological recovery and resilience assessments into environmental risk assessments (ERA). In this commentary we advocate that a systems approach is required to integrate the diversity of ecosystem services (ES) providing units, environmental factors, scales, and stressor-related responses necessary to address the context dependency of recovery and resilience in agricultural landscapes. A future challenge in the resilience assessment remains to identify the relevant bundles of ecosystem services provided by different types of agroecosystem that need to be assessed in concert.

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The Panel on Plant Health performed a pest categorisation of non-EU spp., a well-defined insect genus in the family Cerambycidae (Insecta: Coleoptera). Species can be identified using taxonomic keys at national and regional level, and DNA barcoding.

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Pest categorisation of .

EFSA J

November 2018

The Panel on Plant Health performed a pest categorisation of (Coleoptera: Scarabaeidae) for the EU. is a distinguishable species listed in Annex IAII of Council Directive 2000/29/EC. It is native to Japan but established in the USA in the early 20th century.

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Pest categorisation of .

EFSA J

October 2018

The European Commission requested EFSA to conduct a pest categorisation of (Lepidoptera: Pyralidae), a monophagous moth whose larvae exclusively feed on developing buds, flowers, and fruits of cultivated and wild spp. .  is a species with reliable methods available for identification.

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Pest categorisation of .

EFSA J

October 2018

The EFSA Panel on Plant Health performed a pest categorisation of (Herbst) (Coleoptera: Curculionidae), for the EU. is a well-defined species, recognised as a serious pest of stone and pome fruit in the USA and Canada where it also feeds on a range of other hosts including soft fruit (e.g.

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Pest categorisation of .

EFSA J

October 2018

The European Commission requested EFSA to conduct a pest categorisation of (Coleoptera: Curculionidae), a monophagous pest weevil whose larvae exclusively feed on mango seeds, whereas adults feed on mango foliage. is a species with reliable methods available for identification. It is regulated in the EU by Council Directive 2000/29/EC where it is listed in Annex IIB as a harmful organism whose introduction into EU Protected Zones (PZ) (Alentejo, Algarve and Madeira in Portugal, and Granada and Malaga in Spain) is banned.

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Pest categorisation of spp.

EFSA J

October 2018

The Panel on Plant Health performed a pest categorisation of spp., a well-defined insect genus of the whitefly family Aleyrodidae (Arthropoda: Hemiptera). Difficulties within the taxonomy of the genus give doubt about the ability to accurately identify some members to species level.

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Pest categorisation of .

EFSA J

October 2018

The Panel on Plant Health performed a pest categorisation of the fungus , the causal agent of smut of potato, for the EU. The identity of the pest is well established and reliable methods exist for its detection and identification. is present in Bolivia, Chile, Colombia, Ecuador, Mexico, Panama, Peru and Venezuela.

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Pest categorisation of .

EFSA J

October 2018

The Panel on Plant Health performed a pest categorisation of , the causal agent of black blight of potato, for the EU. The pest is a well-defined fungal species and reliable methods exist for its detection and identification. is present in Bolivia and Peru.

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Pest categorisation of and .

EFSA J

October 2018

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of and , which are well-defined and distinguishable tree fungal pathogens of the family Cronartiaceae. In 2018, these species were moved from the genus to the genus . These pathogens are not known to be present in the EU and are regulated in Council Directive 2000/29/EC (Annex IAI) (as non-European spp.

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Pest categorisation of .

EFSA J

October 2018

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of , a well-defined and distinguishable fungus of the family Melampsoraceae. .  is the causal agent of a leaf and twig rust of hemlocks ( spp.

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EFSA was asked for a partial risk assessment of for the territory of the EU focussing on the main pathways for entry, factors affecting establishment, risk reduction options and pest management. As a polyphagous pest, five commodity pathways were examined in detail. Aggregating across these and other pathways, we estimate that tens of thousands to over a million individual larvae could enter the EU annually on host commodities.

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Plant species mixtures improve productivity over monocultures by exploiting species complementarities for resource capture in time and space. Complementarity results in part from competition avoidance responses that maximize resource capture and growth of individual plants. Individual organs accommodate to local resource levels, e.

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Article Synopsis
  • - The concept that noncrop habitats can improve pest control while supporting biodiversity has gained traction, but the results are inconsistent across different studies.
  • - An analysis of 132 studies showed that while landscape composition often influenced pest and natural enemy populations, the outcomes varied significantly, leading to no definitive improvement in overall pest management.
  • - The findings suggest that noncrop habitats do not uniformly enhance pest control, indicating a need for better guidelines to help farmers understand when habitat conservation will actually benefit crop yields.
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This Guidance describes a two-phase approach for a fit-for-purpose method for the assessment of plant pest risk in the territory of the EU. Phase one consists of pest categorisation to determine whether the pest has the characteristics of a quarantine pest or those of a regulated non-quarantine pest for the area of the EU. Phase two consists of pest risk assessment, which may be requested by the risk managers following the pest categorisation results.

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Background: This study investigated how infestation rates of an important oilseed rape pest, the cabbage seed weevil (Ceutorhynchus obstrictus) and rates of parasitization by its parasitoids are affected by land use, up to 1000 m from 18 focal fields.

Results: The mean proportion of C. obstrictus-infested pods per plant was 8% (2-19.

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