Scientific Opinion on the risks to plant health posed by European versus non-European populations of the potato cyst nematodes Globodera pallida and Globodera rostochiensis


Panel on Plant Health
EFSA Journal
EFSA Journal 2012;10(4):2644 [71 pp.].
Panel members at the time of adoption
Richard Baker, Thierry Candresse, Erzsébet Dormannsné Simon, Gianni Gilioli, Jean-Claude Grégoire, Michael John Jeger, Olia Evtimova Karadjova, Gábor Lövei, David Makowski, Charles Manceau, Maria Navajas, Angelo Porta Puglia, Trond Rafoss, Vittorio Rossi, Jan Schans, Gritta Schrader, Gregor Urek, Johan Coert van Lenteren, Irene Vloutoglou, Stephan Winter and Marina Zlotina

The Panel wishes to thank the members of the Working Group on Potato Cyst Nematodes: Richard Baker, Thomas Been, John Jones, Jan Schans and Gregor Urek for the preparatory work on this scientific opinion, the hearing experts: Eric Grenier and Sue Hockland for their presentations on the biology of the organisms, and EFSA staff: Virág Kertész for the support provided to this scientific opinion.

Opinion of the Scientific Committee/Scientific Panel
On request from
European Commission
Question Number
21 marzo 2012
Published in the EFSA Journal
16 aprile 2012
European Food Safety Authority (EFSA), Parma, Italy

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.

Potato cyst nematodes, Globodera spp., European populations, non-European populations, Solanaceae, genetic variation, virulence
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