First Report of Goss\u27s Bacterial Leaf Blight and Wilt of Corn Caused by \u3ci\u3eClavibacter michiganensis\u3c/i\u3e subsp. \u3ci\u3enebraskensis\u3c/i\u3e in North Dakota

In August of 2011, the North Dakota State University Plant Diagnostic Lab received a hybrid corn (Zea mays) leaf sample from Burleigh County in southcentral North Dakota (ND). The leaf had long, irregular, water-soaked lesions consistent with Goss\u27s leaf blight of corn. Using a light microscope at 10× magnification, bacterial streaming was observed from the excised edge of leaf tissue. A bacterial suspension was created, streaked onto a semi-selective CNS medium (1), and incubated at 22°C. Dark yellow-orange colonies appeared on the medium after 5 days. Single colonies were subcultured onto additional CNS media. To verify the identity of the bacterial isolate, PCR amplification of the 16S ribosomal DNA from this isolate along with a known Clavibacter michiganensis spp. nebraskensis (Cmn) isolate collected in Indiana (4) was performed using the eubacterial universal primers 27f and 1525r (3). The 1,431-bp 16S rDNA region was obtained for each isolate and they were compared with each other and with those deposited in NCBI GenBank