No abstract

The potato cyst nematodes Globodera pallida and G. rostochiensis are listed in the EU Plant Health Directive 2000/29/EC and are also subject to the new EU Council Directive 2007/33/EC on the control of potato cyst nematodes, requiring unilateral suppression of these pests in Europe. At the same time there is also pressure to increase world trade in potatoes. Such pressure has to be balanced by the risks involved in the associated spread of these pests and subsequent problems in management. Populations of the potato cyst nematodes from outside Europe, in particular South America, which is considered the origin of G. pallida and G. rostochiensis, pose a risk to those European countries where limited genetic variability of these nematode species has been recorded. The development and usage of resistant cultivars under such conditions has formed a pivotal role in integrated management programmes in Europe. Molecular studies have shown that populations of G. pallida and G. rostochiensis from South America have a different genetic composition from those in Europe. The introduction of such populations would pose a threat to the use of resistant cultivars as a major tool in reducing the potential spread and damage caused by these species. At present, an inability to link precisely genetic variability to the virulence characteristics of a specific nematode population, and quickly identify the virulence status of intercepted populations for inspection purposes, strengthens the case for using plant health legislation to prevent their introduction.

This pest survey card was prepared in the context of the mandate on plant pest surveillance (EFSA-Q-2017-00831), upon request by the European Commission. The purpose of this document is to assist the Member States in planning annual survey activities of quarantine organisms using a statistically sound and risk-based pest survey approach, in line with the current international standards. The data requirements for such activity include the pest distribution, its host range, its biology, risk factors as well as available detection and identification methods. This document is part of a toolkit that consists of pest-specific documents, such as the pest survey cards and generic documents relevant for all pests to be surveyed, including, the general survey guidelines and statistical software such as RiBESS+.

This pest survey card was prepared in the context of the EFSA mandate on plant pest surveillance (M‐2017‐0137) at the request of the European Commission. The purpose of the document is to assist the Member States to plan annual survey activities of quarantine organisms using a statistically sound and risk‐based pest survey approach, in line with current international standards. The data requirements for such an activity include the pest distribution, its host range, its biology and risk factors, as well as available detection and identification methods. This document is part of a toolkit that consists of pest‐specific documents, such as the pest survey cards, and generic documents relevant for all pests to be surveyed, including the general survey guidelines and statistical software such as RiBESS+.

To gain insight into the different extraction processes used in laboratories in various European countries and the effect these methods might have on the number oi Meloidogyne second-stage juveniles (J2) extracted from soil samples, a ring test with 2 elements was conducted. The first element used the Baermann funnel as a method performance test. The second element was a proficiency test, in which the laboratory's standard technique was compared with the Baermann method. Chilled samples of 100 cm^ (10 per extraction method) were sent to participants in insulated containers. In the nematode counts distinction was made between Meloidogyne J2, other plant-parasitic nematodes and/or saprophytes. A total number of 18 participants took part in the method performance test and 13 institutes took part in the proñciency test using 11 different extraction techniques. The initial population density in the soil was 2025 J2 (100 cm^ soil)"', detemnined by Oostenbrink elutriator and 4 weeks incubation. In the method performance test the institutes found Meloidogyne J2 numbers varied between 0 and 705 J2 (100 cm^)-^ Using the Baermann extraction method the median number per institute ranged from 0 to 377 J2 (100 cm^)~'. In the proficiency test comparison amongst the different methods showed an increase of more than 100-fold, with the highest median of 3733 J2 (100 cm^)"' and the lowest of 34 J2 (100 cm^)"^ the difference was caused mainly by the incubation effect. For the other plant-parasitic nematodes and the saprophytes, the differences between the most and least efficient extraction methods were much smaller. The variance of the Meloidogyne counts was the highest for the standard Baermann extraction technique; other similar techniques also had high variances. The automated zonal centrifuge had the lowest variance. The Baermann method is not advisable for survey purposes.