A Medium for Cultivation of the B-Strain of Xanthomonas campestris pv. citri, Cause of Cancrosis B in Argentina and Uruguay. B. I. Canteros de Echenique, Ingeniero Agrónomo, INTA, Bella Vista, Corrientes, Argentina. D. Zagory, Assistant Research Scientist, Citrus Research and Education Center, IFAS, University of Florida, Lake Alfred 33850; and R. E. Stall, Professor, Department of Plant Pathology, IFAS, University of Florida, Gainesville 32611. Plant Dis. 69:122-123. Accepted for publication 15 July 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-122.

A culture medium was developed to support the growth of the wild-type B-strain of the citrus canker bacterium. Only rare, fast-growing, probably mutant colonies of the B-strain grew on nutrient agar, King’s medium B, Wakimoto’s medium, Emerson’s medium, and several other media. The wild-type B-strain grew only on a medium containing sucrose (1%), peptone (0.5%), dipotassium phosphate (0.05%), magnesium sulfate (0.03%) and Difco purified agar (1.5%). Agars other than Difco purified agar did not support the growth of B-strain bacteria. This medium facilitates studies of the wild-type B-strain canker organism.