Surveys on Clavibacter michiganensis subsp. sepedonicus and Ralstonia solanacearum in Germany
The NPPO of Germany has recently informed the EPPO Secretariat of the results of surveys carried out for Clavibacter michiganensis subsp. sepedonicus and Ralstonia solanacearum (both EPPO A2 quarantine pests) on the 1997 potato harvest and part of the 1998 harvest.
- Clavibacter michiganensis subsp. sepedonicus
Official tests (IF, and in some laboratories IF and PCR) were done in German länder for latent infections in seed and ware potatoes. In addition, visual inspections were also carried out. The number of infested lots found in 1997/1998 was twice as high as in 1996. The origin of these infestations is not known.
1997 harvest: 13,953 samples were tested (10,987 seed potatoes - 2,966 ware potatoes) and 23 positive cases were found on seed potatoes and 41 on ware potatoes.
1998 harvest (in part): so far, 13,800 samples have been tested (10,476 seed potatoes - 3,324 ware potatoes) and 18 positive cases were found on seed potatoes and 28 on ware potatoes.
Phytosanitary measures are being applied aiming at the eradication of the disease.
- Ralstonia solanacearum
Concerning the 1997 harvest, 13,029 samples were tested in the laboratory following the EU protocol, and additional visual inspections were done. R. solanacearum was only found in 2 cases (ware potatoes) at harvest time. In Bayern, the bacterium was found in 2 water samples in a small river and in 1 sample of Solanum dulcamara. Tests were done in this river, because it received liquid waste from a potato factory which had processed some infected potatoes in 1996. Strict phytosanitary measures are applied to control the bacterium and prevent any further spread, and it is expected to eradicate it in a near future.
Sources
NPPO of Germany, 1999-03.