Pest survey card on Geosmithia morbida and its vector Pityophthorus juglandis

Abstract

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 Geosmithia morbida and Pityophthorus juglandis surveys. These are required to design statistically sound and risk-based pest surveys, in line with current international standards.Geosmithia morbida and its vector P. juglandis are clearly defined taxonomic entitiesand the combined activity of the fungus and the insect causes the disease complex thousand canker disease on the plant genera Juglans and Pterocarya. The pest and its vector originate in North America and currently have a restricted distribution in the EU, limited to the northern parts of Italy.However, they are potentially able to become established everywhere in the EU where their host plants occur.Currently, the spread capacity ofP.juglandis is unknown, but the insect vectormay cover large distances by passive dispersal or human-assisted spread. Risk locations include entry points (e.g. seaports, airports), loading stations, storage facilities and wood processing companies that deal withheat-treated wood, bark or woodchips of the genera Juglans and Pterocarya originating from countries where the fungus and its vector occur.Trapping is the recommended method for detecting the vector inthe early stages of an epidemic. Following insect trapping, a specific tree inspection should be carried out, looking for external symptoms(e.g. penetration and exit holes, cankers and wilting). The trapping should start when the mean air temperature exceeds 18°C.Morphological identification of the pathogen and its vector should be performed by experts. Molecular assays are also available for both fungal and vector identification.