First report of ‘Candidatus Phytoplasma ulmi’ in Belgium
In Belgium, ‘Candidatus Phytoplasma ulmi’ (EPPO A1 List*) was first found in May 2018 in a single Ulmus tree in the Botanic Garden of Meise, near Brussels. This finding was made during survey activities carried out in the framework of a scientific research project supported by the Belgian NPPO. The identity of the pathogen was confirmed by molecular tests (PCR, sequencing). At the time of sampling, the elm tree was still dormant and without any leaves. In May, it was still asymptomatic. Further investigations did not detect ‘Ca. P. ulmi’ in other plants. The NPPO decided not to destroy this single and asymptomatic tree but further monitoring is ongoing to establish the status of ‘Ca. P. ulmi’ in Belgium.
The pest status of ‘Candidatus Phytoplasma ulmi’ in Belgium is officially declared as: Present, only in some parts of the Member State concerned.
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* Note: Although phytoplasma diseases observed in elms in North America (elm phloem necrosis) and in several European countries (elm yellows) have different symptomatologies, the phytoplasmas associated with them are very closely related if not belonging to the same species ‘Ca. Phytoplasma ulmi’. Therefore, the inclusion of this pathogen on the A1 List (absent from the EPPO region) might need to be reconsidered
Sources
NPPO of Belgium (2018-06).