Situation of Burkholderia (Pseudomonas) solanacearum in the EPPO region
Burkholderia (Pseudomonas) solanacearum (EPPO A2 quarantine pest) in the last few years has been reported at a number of locations in northern Europe (e.g. RS 96/001), and is continuing to be so reported. The EPPO Secretariat has accordingly sent a questionnaire to all its member countries in order to clarify the situation of potato brown rot throughout the EPPO region. The replies are summarized here.
Austria: B. solanacearum did not occur in Austria in the past. Recently, IF-positive results were obtained for three samples and biological tests on tomatoes are being made. Further monitoring is being carried out.
Belgium: Prior to 1989, B. solanacearum was never found in Belgium. A small area near the border with the Netherlands was found to be infested over the years 1989-1991, and strict survey and control measures were imposed (see EPPO RS 93/070). Cultivation of potatoes was prohibited in a quarantine area of several communes around the infected plots. Intensified surveillance was applied to potato crops all over Belgium, with laboratory testing of seed potato samples, regular visual inspection of seed potato crops throughout Belgium. No case of potato brown rot was found in seed potatoes. Since 1992, intensive surveys have been carried out for ware potatoes and seed potatoes. 20 % of seeds potatoes produced in Belgium have been tested in the laboratory, production fields have been inspected at least twice a year and all lots have been visually inspected. In 1993 and 1994, only a single case of infestation per year was found and infected crops were destroyed. Since then, B. solanacearum has not been found in Belgium, and in particular has not been found in any of the production sites of ware potatoes where the disease was found in previous years. These results indicate that the disease has been eradicated. The official authorities consider that Belgium is now free from B. solanacearum.
Bulgaria: B. solanacearum was reported for the first time in Bulgaria on tomato in 1944, and was then observed in 1951 on sunflower. These two foci were eradicated and since then B. solanacearum has not been found in Bulgaria. Inspections carried out in 1994 and 1995 have not revealed the presence of the bacterium.
Croatia: B. solanacearum has never occurred in Croatia.
Cyprus: B. solanacearum was found only once on potatoes in October 1955 in 'Shia Village' which is not a traditional potato-growing area. Eradication measures were applied and the disease was not further reported. The official authorities consider that Cyprus is now free from B. solanacearum. The last EPPO Distribution List for B. solanacearum (EPPO RS 94/227) which mentioned the disease as present has to be modified accordingly.
Czech Republic: B. solanacearum has never been found in Czech Republic.
Denmark: B. solanacearum has not been found in Denmark in 1994 and 1995. This disease has never occurred in Denmark. A previous EPPO record refers to an interception on ornamental Musa only.
Estonia: B. solanacearum has never occurred in Estonia.
Finland: B. solanacearum has never been found in potatoes grown in Finland but has been intercepted on ware potatoes from Egypt.
Germany: B. solanacearum has never occurred in Germany in the past, and in particular it has not been found in 1994 or 1995.
Guernsey: B. solanacearum has never occurred in Guernsey.
Hungary: Visual examination and laboratory tests carried out in Hungary have shown that B. solanacearum is not present in the country. No infection was found in any tested samples of imported seed potatoes.
Ireland: B. solanacearum has never been found in Ireland. All surveys gave negative results.
Israel: At present, potato brown rot does not occur in Israel and is considered as a quarantine pest. In the early 1970s, it was found in several potato fields in one location in Israel but was successfully eradicated. In 1993, a survey was carried out throughout the country and concerned potato brown rot, potato ring rot (Clavibacter michiganensis subsp. sepedonicus) and potato spindle tuber viroid. None of these diseases was found. In 1994, B. solanacearum has been found in Curcuma plants grown in glasshouses from bulbs imported from the Netherlands. Measures were immediately taken, including destruction of all infected bulbs and plants, and fumigation with formaldehyde.
Italy: Before 1995, this disease was never found in Italy. During June 1995, foci of potato brown rot have been suspected in Veneto and Emilia-Romagna after import of infected seed potatoes. These certified seed potatoes (cvs. Primura and Liseta) were imported from the Netherlands. The infected potatoes were destroyed and phytosanitary measures have been taken to eradicate these foci and to prevent further spread of the disease to other potato fields and other solanaceous crops. In addition, the Ministry of Agriculture has taken measures at the EU level regarding the marketing of seed potatoes from the Netherlands to prevent further introductions into Italy.
Jersey: B. solanacearum has never been found in Jersey. In 1995, symptoms on tomato were found suspicious but during tests, B. solanacearum was not isolated.
Latvia: B. solanacearum is not present in Latvia. Few reports were made in the past but have never been confirmed.
Malta: B. solanacearum has never occurred in Malta.
Netherlands: So far, B. solanacearum has been found in 38 farms and strict phytosanitary measures are being taken to prevent further spread. See EPPO RS 96/001.
Norway: B. solanacearum has never occurred in Norway.
Poland: There are reports of B. solanacearum before 1945 but these are probably based on misidentifications. Since 1945, this pathogen has never been recorded in Poland.
Romania: An occurrence of B. solanacearum has been reported only once in the Romanian literature, in 1957. The bacterium has never been identified by the Central Quarantine Laboratory (including in 1994 and 1995), and it is considered that the disease is not present in Romania.
Slovak Republic: B. solanacearum has never occurred in Slovak Republic.
Slovenia: B. solanacearum has never occurred in Slovenia.
Sweden: An infestation was reported in 1976 (in the EPPO Bulletin 6(4), 199-207) and was later eradicated. Tests have been carried out on Solanum dulcamara in the streams of the earlier infested areas in 1994. None of the tested plants was infested. The official authorities consider that Sweden is free from B. solanacearum.
Switzerland: B. solanacearum is not present in Switzerland, and no symptoms have been seen during the recent period of outbreaks elsewhere in Europe.
Tunisia: B. solanacearum has been reported in the past, in a limited area. However, observations on seed and ware crops of potato over the last two years have revealed no case of the disease.
Turkey: The disease is considered as absent in Turkey. It has been found in the past but is not established. However, in early 1995 some infected potato tubers (cv. Van Gogh) were found in a small part of Central Anatolia region. Intensive surveys have been set up and eradication measures are being applied.
Ukraine: According to the inspections and analysis carried out in Ukraine, B. solanacearum is not present.
United Kingdom: Only one isolated incidence of potato brown rot has been reported in United Kingdom, in the Oxfordshire region of England in 1992 (see EPPO RS 93/031). The farm in question has been under control since that time. Although infection was found in one or two "ground keeper" or "volunteer" tubers in the following season, no further re-occurrence of the disease has been discovered. Extensive surveys of both ware and seed crops have been conducted since this outbreak. No further infections in potato crops have been found. In the light of this outbreak, extensive surveying of watercourses in the country has been undertaken to determine whether infected weeds on river banks are acting as a reservoir for this organism. Apart from one isolated occurrence involving two infected plants which were removed, the organism is present only in the Thames river basin in infected Solanum dulcamara plants on the river banks. Consideration is being given to possible action related to these infected plants but in the meantime ware potato growers (no seed potatoes are grown in this area) have been advised on the dangers of irrigating from this infected water source. It may be noted that B. solanacearum has occasionally been intercepted on imported ware potatoes.
No replies have been received from: Albania, France, Greece, Luxembourg, Morocco, Portugal, Russia and Spain. According to the data in the EPPO PQR system, B. solanacearum has been reported in Greece, Morocco, Russia (not apparently on potato). It has occurred but was eradicated in Portugal. In Spain (RS 95/011), it occurred in 1981 in the Canary Islands and was eradicated (never found on the mainland). In the 1970s, Yugoslavia reported B. solanacearum to be present locally, as was given in the first edition of the EPPO data sheet. In view of the declarations from Croatia and Slovenia, the affected regions must be elsewhere in ex-Yugoslavia. In the EPPO region, there are also records in: Algeria (not in coastal region), Armenia, Belarus (unconfirmed), Egypt, Georgia, Lebanon, Libya, Moldova.
Sources
EPPO Secretariat, 1995-12.