Microorganisms
All microorganisms used in this study were provided by the
Department of Plant Pathology, University of the Free State,
Bloemfontein, South Africa. Five plant pathogenic test bacteria
were used for screening purposes including
Agrobacterium tumefaciens Smith and Townsend,
Clavibacter michiganense Spieckermann pv. michiganense
Smith, Erwinia carotovora pv. carotovora Jones,
Pseudomonas solanacearum Smith and Xanthomonas
campestris Pammel pv. phaseoli Smith.