Ralstonia solanacearum found on glasshouse tomatoes in Sardegna (IT)
A new outbreak of Ralstonia solanacearum (EPPO A2 List) was detected in 2009 in a glasshouse tomato crop (Lycopersicon esculentum cv. ‘Cuore di bue’ grafted on Beaufort) in Sardegna, Italy. Surveys were conducted in 4 glasshouses (called As-1, As-2, As-3 and As-4 in this study) where plants showing bacterial wilt symptoms were observed. The percentage of symptomatic plants ranged from 10% to 50%. In one of these glasshouses (As-1), R. solanacearum had been detected in 2007 (Loreti et al., 2008) and subsequently eradicated by uprooting and burning tomato plants, methyl bromide treatment and decontamination of stored water with a sodium chloride solution. Samples from plants, soil and water were collected from As-1 and As-2, whereas only plant samples were collected from As-3 and As-4. Results of the analysis (isolation on semi-selective media, biochemical and IF tests, inoculation of tobacco leaves) showed that R. solanacearum was only found in plant and soil samples collected from glasshouse As-2 (neighbouring glasshouse As-1), and phylotype characterization showed that all recovered isolates belonged to phylotype II. The authors considered that this new outbreak raised serious concerns because the causes underlying the introduction and dissemination of R. solanacearum in Sardegna are still unknown.
Sources
Fiori M, Gallelli A, Fiori V, Ligios V, Loreti S (2009) A new outbreak of Ralstonia solanacearum on tomato in Sardinia. Plant Pathology 91(4 suppl.), S4.103.
Loreti S, Fiori,M, De Simone D, Falchi G, Gallelli A, Schiaffino A, Ena S (2008) Bacterial wilt, caused by Ralstonia solanacearum, on tomato in Italy. Plant Pathology 57(2), p. 368.