Incursion of Stolbur phytoplasma in potatoes in Germany
The German NPPO recently informed the EPPO Secretariat of the first incursion of stolbur phytoplasma (EPPO A2 list) in potatoes in Germany (Hesse). In August 2006, symptoms of potato stolbur (aerial tubers, discoloured reddish leaves, quick decay of the plants) were detected in potato plants at a company producing ware potatoes. This suspicion was confirmed by PCR. The phytoplasma was only detected in the tubers and stems, but not in the aerial tubers. Weeds growing nearby the field edges were inspected and symptomatic plants of Convolvulus arvensis were observed. Laboratory tests showed that they were infected by the same type of phytoplasma. The origin of the infection is not known. Planting material as a possible source of infection may be excluded, and it is more probable that the phytoplasma was spread by insect vectors from latently infected weeds. The grower will not be allowed to use potatoes of the infected lot as seed potatoes and to plant potatoes in the infected field. During the next vegetation period, suitable measures will be taken to eradicate weeds in the neighbourhood of the infected field. Potato fields and their surroundings will intensively be inspected for symptoms of stolbur phytoplasma.
The pest status of stolbur phytoplasma on potatoes in Germany is officially declared as follows: Single limited incursion; under eradication.
NPPO of Germany, 2006-11.