Pest categorisation of Gymnosporangium spp. (non‐EU)

bonsai, European Union, latent infection, pest risk, plant health, plant pest, quarantine
First published in the EFSA Journal
19. Dezember 2018
22. November 2018
Scientific Opinion


Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Gymnosporangium spp. (non‐EU), a well‐defined and distinguishable group of fungal plant pathogens of the family Pucciniaceae affecting woody species. Many different Gymnosporangium species are recognised, of which at least 14 species are considered not to be native in the European Union. All the non‐EU Gymnosporangium species are not known to be present in the EU and are regulated in Council Directive 2000/29/EC (Annex IAI) as harmful organisms whose introduction into the EU is banned. Gymnosporangium spp. are biotrophic obligate plant pathogens. These rust fungi are heteroecious as they require Juniperus, Libocedrus, Callitropsis, Chamaecyparis or Cupressus (telial hosts) and rosaceous plants of subfamily Pomoideae (aecial hosts) to complete their life cycle. The pathogens could enter the EU via host plants for planting (including artificially dwarfed woody plants) and cut branches. They could establish in the EU, as climatic conditions are favourable and hosts are common. They would be able to spread following establishment by movement of host plants for planting and cut branches, as well as by natural dispersal. Should Gymnosporangium spp. (non‐EU) be introduced in the EU, impacts can be expected in orchards, ornamental trees and nurseries. On telial hosts, these pathogens cause galls on stems, twigs and branches, and fusiform swellings on stems. Foliar infections on aecial hosts may lead to severe defoliations. The main knowledge gap concerns the limited available information on the biology, distribution range and impact of several non‐EU Gymnosporangium spp. The criteria assessed by the Panel for consideration of Gymnosporangium spp. (non‐EU) as potential quarantine pests are met, while, for regulated non‐quarantine pests, the criterion on the pest presence in the EU is not met.

Panel members at the time of adoption

Claude Bragard, Katharina Dehnen‐Schmutz, Francesco Di Serio, Paolo Gonthier, Marie‐Agnès Jacques, Josep Anton Jaques Miret, Annemarie Fejer Justesen, Alan MacLeod, Christer Sven Magnusson, Panagiotis Milonas, Juan A. Navas‐Cortes, Stephen Parnell, Roel Potting, Philippe L. Reignault, Hans‐Hermann Thulke, Wopke Van der Werf, Antonio Vicent, Jonathan Yuen and Lucia Zappalà
Panel on Plant Health
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EFSA Journal 2018;16(12):5512
Question Number
On request from
European Commission