Phytosanitary incident with Ralstonia solanacearum in Morocco
The EPPO Secretariat was notified of two French interceptions of ware potatoes (7.560 t of cv. Diamant and 68.947 t of cv. Nicola) from Morocco infected by Ralstonia solanacearum (EPPO A2 quarantine pest). Laboratory tests including biological assays carried out in France confirmed the presence of the bacterium in the two lots. Following these interceptions, the Plant Protection Service of Morocco made further enquiries to identify fields where infected potatoes had been grown, and to trace back the origin of the seed potatoes used. For the potato lot of cv. Diamant, two production fields were identified at El-Jadida (south-west of Casablanca). For this cultivar, the seed potatoes used came exclusively from the Netherlands. Concerning the other lot of potatoes cv. Nicola, three production sites could be identified and were located in the region of Larache (approximately 200 km north of Rabat). For this cultivar, several countries including France, Ireland, Netherlands and Denmark had provided seed potatoes during the last growing season.
Considering the importance of this bacterium, the following measures have been taken by the Plant Protection Service of Morocco: 1) the five production sites have been placed under quarantine, 2) cultivation of potential host plants of R. solanacearum is prohibited on these fields, 3) the phytosanitary status of these five fields is currently checked by testing volunteer plants and so far, the bacterium has not been found, 4) a national survey will be carried out in potato production fields with a particular intensity in production sites for export.
Sources
Plant Protection Service of France, 1997-12.
Plant Protection Service of Morocco, 1997-12.