The invention provides isolated Erwinia persicina strains with activity against: a) at least one Xanthomonas species, and/or b) at least one Brassicaceae pathogen. In particular the invention provides the isolated E. persicina strains deposited as DSM 32302, DSM 32304, DSM 32305 and DSM 32303. The invention provides compositions comprising one or more strains of the invention. The invention also provides methods of use of one or more strains or compositions of the inventions to control plant pathogens, particularly Xanthomonas campestris pv. campestris.