Occurrence of ‘Candidatus Phytoplasma pyri’ is confirmed in Belgium
In Belgium, symptoms of pear decline had been observed in some orchards but the presence of ‘Candidatus Phytoplasma pyri’ (EPPO A2 List) had not been confirmed by molecular tools. In October 2010, 137 samples mainly consisting of leaves showing early yellow or red discoloration were collected from 14 pear production orchards in the north-east of Belgium. This sampling was part of an NPPO research project on the occurrence of phytoplasmas in apple and pear production in Belgium. As the first part of the project dealt with ‘Candidatus Phytoplasma mali’ (results were reported in EPPO RS 2011/132), these 137 samples were stored at -20°C. Molecular analysis (PCR) was performed by the end of 2011 and approximately 15% of the 137 samples were found positive for ‘Ca. P. pyri’. These positive samples originated from 8 of the 14 inspected symptomatic orchards. The NPPO of Belgium is currently focussing its official inspections on the production of propagation material and fruit trees. Prescribed measures in nurseries involve the destruction of all symptomatic plants upon confirmation of an infection, and the inspection of the edges of neighbouring fields planted with susceptible host plants. The NPPO will conduct further research in order to determine the exact distribution of ‘Ca. P. pyri’ across Belgium and investigate the role of local insect vector populations in its dispersal.
The pest status of ‘Candidatus Phytoplasma pyri’ in Belgium is officially declared as: Present, restricted distribution, found in some production orchards, under surveillance.
Sources
NPPO of Belgium (2012-10).