Ralstonia solanacearum found again in Belgium
In the past, Ralstonia solanacearum (EPPO A2 quarantine pest) had been found in a limited area in Belgium (see EPPO RS 96/002, 96/183, 97/111) but was successfully eradicated in 1998. Regular surveys are still being carried out. The NPPO of Belgium recently informed the EPPO Secretariat that in autumn 1999, R. solanacearum was detected in a potato production area in the north of the Province of Limburg, near Maaseik. The bacterium was detected in 8 ware potato fields belonging to 4 growers (20.8 ha). During the regular annual survey on brown rot in Noorderkempen (Provinces of Antwerp and Limburg), R. solanacearum was detected in 7 additional ware potato fields belonging to 5 growers (36.6 ha), near Lommel. In September 1999, the Dutch NPPO had intercepted one consignment of ware potatoes harvested from this area (see EPPO RS 2000/071). Due to a combination of circumstances, this potato field was harvested and transported to the Netherlands for processing before an inspection by the Belgian NPPO could take place.
It is thought that the present outbreak is due to irrigation with contaminated surface water during the potato growing season. At the time of the first finding, 25 water samples (out of 48 taken from a watercourse which was used to irrigate the infected crops) were tested and gave positive results. In previous years, all tested water samples had given negative results.
Strict phytosanitary measures have been taken to prevent any further spread and to eradicate R. solanacearum according to Council Directive 99/57/EC. In particular, from 2000-02-14, it is prohibited to use surface water to irrigate potato, tomato and aubergine crops. Studies are also being carried on the possibilities for eradicating Solanum dulcamara from watercourse banks.
NPPO of Belgium, 2000-03.