Updated situation of ‘Candidatus Phytoplasma mali’ in Norway
In Norway, ‘Candidatus Phytoplasma mali’ (associated with apple proliferation - EPPO A2 List) was detected for the first time in 1996. In 2009, regular surveys were initiated (see also EPPO RS 2011/133 which presented the results for the period from October 2009 until March 2011). In 2011, an official survey was conducted in 46 commercial orchards and 34 private gardens on Malus spp. (mainly Malus domestica). In total, 250 samples were tested (by PCR) and 139 were found to be infected. ‘Ca. P. mali’ was detected in several municipalities in the following counties:
- Buskerud (5 findings in Lier – 1 in Øvre Eiker),
- Hordaland (21 findings in Ullensvang – 1 in Ulvik),
- Sogn og Fjordane (5 findings in Sogndal, 3 in Leikanger, 1 in Gloppen, 1 in Aurland),
- Telemark (5 findings in Sauherad),
The pathogen was detected in apple trees (in different 15 M. domestica cultivars) and in a few ornamental Malus. All infested host plants were destroyed and chemical treatments were applied against insect vectors when a risk of spread to nurseries was perceived. Official surveys will continue in 2012 in fruit orchards and private gardens located in the vicinity of nurseries producing Malus, and official production controls will be intensified in nurseries.
The pest status of ‘Candidatus Phytoplasma mali’ in Norway is officially declared as: Present, only in some areas, subject to official control.
NPPO of Norway (2012-07).