5th meeting of the EPPO Panel on Diagnostics in Virology and Phytoplasmology

Bari (IT), 2017-11-20/21

 

 

The 5th meeting of the EPPO Panel on Diagnostics in Virology and Phytoplasmology took place in Bari, Italy. The Panel continued its task of developing diagnostic protocols for regulated viruses, viroids and phytoplasmas, and was followed by the ‘Workshop on the use of Next Generation Sequencing technologies for plant pest diagnostics’.

 

General discussions

 

Flexible scope

The EPPO Secretariat presented the main results of the Workshop on flexible scope held on 2017-06-26/28 in Wageningen, NL. Details of the Workshop are available here. The main conclusion was a revision of the 2 EPPO Standards: PM 7/84 (1) Basic requirements for quality management in plant pest diagnosis laboratories and PM 7/98 (2) Specific requirements for laboratories preparing accreditation for a plant pest diagnostic activity that should be prepared to include recommendations on how to implement flexible scope. A drafting group revised these Standards which were sent for country consultation in early 2018 and it is expected that they will be adopted later in 2018.

 

Validation data for EPPO Diagnostic Protocols

The Panel was informed that a project proposal on validation of diagnostic tests to support plant health was submitted for the H2020 topic SFS13 Validation of diagnostic tools for animal and plant health. The project has now been accepted and will allow a number of activities to be undertaken, including the improvement of the EPPO Database on Diagnostic Expertise.

 

Interpretation of results for conventional PCR

The Panel noted that in case of variant and recombinant of virus, the bands produced with a Conventional PCR may have a different size from those expected; they considered that this should be indicated in the instructions to authors in the section on the interpretation of results. This issue will be considered at the next meeting of the Panel on Diagnostics and Quality Assurance.

 

Discussion on the inclusion of Next Generation Sequencing in Diagnostic Protocols

In the framework of the discussion on Plum pox virus, Andean potato latent virus (APLV) and Andean potato mild mosaic virus (APMMV), the inclusion of Next Generation Sequencing (NGS, also referred to as High Throughput Sequencing HTS) in Diagnostic Protocols was discussed. It was noted that NGS technologies are already used in a number of laboratories. The Panel agreed that a reference to NGS could be made in diagnostic protocols.

 

 

Discussions on pest-specific diagnostic Standards

Alignment of EPPO Diagnostic Protocols with IPPC protocols

PM 7/32 Plum pox virus

The alignment of the EPPO Diagnostic Protocol with the IPPC protocol (ISPM 27 Annex 02) was discussed. In addition to the tests included in the IPPC protocol a new real-time PCR test under development in Naktuinbouw (NL) and a LAMP test from IpadLab-International Plant Analysis & Diagnostics srl will be included in the EPPO Diagnostic Protocol. A new version of the Diagnostic Protocol taking into account the discussion of the Panel will be prepared and sent for country consultation.

 

PM 7/33 Potato spindle tuber viroid

The pest will be covered in the EPPO Diagnostic Protocol on Pospiviroids, and a separate Standard will no longer be needed. However, attention will be paid that the information on the pest will be aligned with the IPPC Standard ISPM 27 Annex 7 and included in the general Standard.

 

PM 7/31 Citrus tristeza closterovirus

The alignment of the EPPO Diagnostic Protocol PM 7/31 Citrus tristeza closterovirus to the IPPC Standard (ISPM 27 Annex 15) will be prepared by the end of June 2018.

 

 

EPPO Diagnostic Standards

New pest-specific diagnostic Standards:

 

Andean potato latent virus (APLV) & Andean potato mild mosaic virus (APMMV)

The Panel finalized a new diagnostic protocol on Andean potato latent virus (APLV) & Andean potato mild mosaic virus (APMMV) which has now been sent be sent for country consultation.

 

Tomato leaf curl New Delhi virus

A Diagnostic Protocol for generic detection of Begomoviruses will be prepared for the next meeting of the Panel and will include pest-specific tests including tests for Tomato leaf curl New Delhi virus. An IPPC Protocol is also in preparation and the authors will ensure that both documents are aligned. A drafting team was established.

 

Standard on the generic detection of Pospiviroids

The Panel made good progress on the text prepared by a drafting team for this generic protocol, in particular deciding whether all tests mentioned are relevant. Further modifications will be made by correspondence and the Panel agreed that the Standard should be sent for country consultation.

 

Standard on the generic detection of Orthotospoviruses

This Diagnostic Standard will replace PM 7/34 on Tomato spotted wilt tospovirus, Impatiens necrotic spot tospovirus and Watermelon silver mottle tospovirus, as the revision covers the detection and identification of all Orthotospoviruses. A new version of the Diagnostic Protocol will be prepared to be sent for country consultation.

 

Standard on the generic detection of Phytoplasmas

The draft Diagnostic Protocol was prepared by the EPPO Secretariat based on the IPPC Diagnostic Protocol. The Standard has now been sent for country consultation.

 

 

Revision of existing pest-specific diagnostic Standards

 

PM 7/49 Tomato ringspot virus

The discussion on the revision of the EPPO Diagnostic Protocol PM 7/49 Tomato ringspot virus was postponed to the next meeting as no progress could be made on the text by the main author.

 

PM 7/30 Beet necrotic yellow vein virus (Benyvirus)

A revision of the Diagnostic Protocol on Beet necrotic yellow vein virus is in progress. Work will continue via correspondence.

 

 

Future priorities for revision of pest-specific protocols and future programme

The Panel reviewed the list of EPPO Diagnostic Protocols in Virology and Phytoplasmology to confirm stewards, agree on priorities and plan future work. The proposal to prepare generic Standards on Poleroviruses, Nanoviruses and Potyviruses were made.

 

 

Discussions on Quality assurance

ISO/CD 13484 General requirements for molecular biology analysis for detection and identification of destructive organisms in plants and derived products

A new draft of the ISO Standard was circulated shortly after a meeting that took place in Washington on the 2017-09-04/08 to gather comments from the National Accreditation bodies. EPPO organized a teleconference to discuss the document and NPPOs were asked to contact the Standardisation bodies to express concerns on that Standard. The Standard was disapproved and EPPO will continue to follow the decision made by ISO on possible further work on this Standard.

 

The next meeting of the EPPO Panel on Diagnostics in Virology and Phytoplasmology will be held in ANSES in Maisons-Alfort (FR), near Paris.