Characterization of Xanthomonas euvesicatoria strains pathogens of pepper in Serbia

During spring and summer of 2008, 101 bacterial strains was isolated from the diseased pepper leaves collected from different pepper growing areas in the Republic of Serbia. The aim of this research was to characterize the isolated strains and determine their taxonomic position according to the most recent nomenclature. Pathogenic, biochemical and physiological characteristics of isolated bacteria were tested using standard bacteriological tests. The pathogen races were determined according to the reaction of differential varieties of Early Calwonder (ECW), their isogenic lines (ECW-10R, ECW-20R, ECW-30R) and Capsicum pubescens. The sensitivity of strains to bactericides was studied in vitro by culturing bacteria on sucrose pepton agar (SPA) plates, amended with filter-sterilized aqueous solution of streptomycin and kasugamycin (50, 100, 200 ppm) or copper-sulphate (100, 200 ppm). Based on pathogenic, biochemical and physiological characteristics, the investigated strains belonged to Xanthomonas euvesicatoria. The reaction of pepper differential varieties indicated that these strains belonged to pepper races P1, P3, P7, P8. Streptomycin resistant strains were not detected, but 6 strains were resistant to kasugamycin (50 ppm) and 13 strains to copper-sulphate (200 ppm), indicating bacterial resistance development.