Characterization of Xanthomonas campestris pv. vesicatoria from Capsicum annuum in Italy
In summers 1991 and 1992, 38 strains of Xanthomonas campestris pv. vesicatoria (EPPO A2 quarantine pests) have been isolated from pepper leaves and fruits (Capsicum annuum) in regions of Italy where the disease is present (central and southern regions), and characterized. Samples were collected in Lazio, Marche, Toscana, Umbria and Puglia regions, the pathogen was isolated and the pathogenic races determined by using differential pepper cultivars (different lines of cv. Early Calwonder, carrying single dominant genes Bs1, Bs2 and Bs3 conferring resistance to three races). The aim was to determine which pepper races were present in Italy and whether they were copper and/or streptomycin-resistant. The results showed that races 1, 2 and 3 are present on pepper in Italy, respectively 39 %, 16 % and 45 % of the tested strains. Races 3 and 1 are the predominant races (84 % of the tested strains). Race 2 was only detected in 1991. Among all tested strains, 45 % were resistant to copper sulphate but none was found resistant to streptomycin sulphate (note that antibiotics are not permitted in Italy). All strains belonging to race 2 and 73 % of race 1 were resistant to copper, while all race 3 strains were sensitive to copper.
Sources
Buonaurio, R.; Stravato, V.M.; Scortichini, M. (1994) Characterization of Xanthomonas campestris pv. vesicatoria from Capsicum annuum L. in Italy
Plant Disease, 78 (3), 296-299.