Phytosanitary incident: potato spindle tuber pospiviroid found and eradicated in France
Within the framework of a breeding programme, four African potato cultivars (Solanum tuberosum cv. Mabondo 2, Mabondo, 21, Kirundo and Sangema) were imported from Belgium and studied in a breeding research station in Bretagne (France) for the production of mini-tubers. These cultivars were in particular tested for the presence of viroids and phytoplasmas. In mid-January 2001, cv. Mabondo 2 was found infected by potato spindle tuber pospiviroid (PSTVd - EPPO A2 quarantine pest). Eradication measures were taken, the potato lot concerned was destroyed and all other lots which may have been in contact with it were tested and found free from the viroid. As a consequence, a notification of interception was sent to Belgium. In return, France was informed that another breeding station in the north of France had also received the same four African potato cultivars for collection purposes. From March to April 2001, 88 in vitro potato clones of the breeding station were tested. As a result, PSTVd was detected in 9 clones, of which several were already grown and multiplied under glasshouses. It was immediately decided to set up a testing programme of potato material originating from the breeding station (first two generations of multiplication), either grown under glasshouse or in the field. In addition, potato material from another potato collection was tested. As a result, 5000 tests were done. On potato material grown in glasshouses: PSTVd was found in 14 glasshouses, located in Nord Pas de Calais, Haute Normandie, Picardie, Champagne-Ardenne, Ile de France. On potato material grown in the field: PSTVd was found on 17 clones grown on 14 farms (corresponding to 14 fields) located in the same regions as above (except Ile de France). Phytosanitary actions were immediately taken: destruction of all infected material (including potato grown in the vicinity of infected fields), prohibition to move all pre-basic and basic potato material produced in the north region awaiting for more tests to be performed. From October 2001 to February 2002, 68500 analyses were done on all pre-basic and basic seed potato lots. On pre-basic material, no infection was found, but 7 lots of basic material were found infected. Eradication measures were applied to these lots. The origin of this infection could not be traced. Today, the NPPO of France considers that PSTVd has been eradicated. However, a surveillance programme including 20,000 tests is being set up to confirm the absence of PSTVd in the 2002 potato harvest.
The situation of potato spindle tuber pospiviroid in France can be described as follows: Absent, found in a few imported potato lots, eradicated.
NPPO of France, 2002-08