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. Its purpose is to guide the Member States in preparing data and information for surveys ofPseudomonas syringaepv. actinidiae(Psa). These are required to design statistically sound and risk‐based pest surveys, in line with current international standards.Pseudomonas syringaepv. actinidiaeis one of over 60 Pseudomonas syringae pathovars, and the causal agent of kiwifruit bacterial canker. Pseudomonas syringaepv. actinidiaeis present in several kiwifruit‐growing areas in the EU and is expected to be able to become established in most or all of them. For surveillance, Actinidia chinensisvar.deliciosaand A. chinensisvar.chinensisare the most relevant hosts.The pathogen is subject to emergency measures aiming to prevent further spread of the pathogen in the EU. The most likely pathway for introduction ofthe bacteriumis through the transport of infected plants for planting and pollen. Once introduced, further natural spread is expected to occur rapidly. Itis most easily detectedby visual examination, although other bacteria can cause similar symptoms. Hence, it needs to be followed by sampling and laboratory identification.

Ralstonia pseudosolanacearum, a European Union quarantine organism, was until recently absent in the aquatic environments and outdoor cultivation systems inside the region. This bacterium was only sporadically reported in restricted greenhouse cultivation systems in some EU countries. In this paper we report the first findings of R. pseudosolanacearum (phylotype I) in surface water in two distinct geographic locations in the Netherlands in 2020. In 2021, the population of Ralstonia pseudosolanacearum in surface water was ranging between 104 – 106 CFU/l. An inoculum reservoir for R. pseudosolanacearum in these aquatic environments was the wild bittersweet plant where population densities were ranging from 105 – 107 CFU/ml concentrated bittersweet extract. The virulence of the R. pseudosolanacearum isolates from surface water and bittersweet was confirmed by a pathogenicity test on Solanum lycopersicum cv. Moneymaker plants, resulting in wilting and necrosis of the plants. Sequence analysis of the egl locus of R. pseudosolanacearum isolates from surface water and bittersweet revealed that these isolates are closely related to R. pseudosolanacearum (phylotype I) isolates found previously in the Netherlands on rose. R. pseudosolanacearum (phylotype I) has a very broad host plant range, including potato, many ornamental and other economically important crops. This highlights the risk for various host plants grown in the vicinity of the geographic locations where R. pseudosolanacearum has been found and shows the importance of unraveling the epidemiological parameters of the survival, establishment and spread of R. pseudosolanacearum in temperate climates.

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