FIGURE 4.

Colony characteristics of Clavibacter nebraskensis strains isolated from Goss's wilt symptoms of maize tissues on nutrient broth‐yeast extract (NBY) medium. Growth on NBY medium is slow, with visible colonies rarely appearing before 3–4 days (a). The bacterium produces orange fluidal colonies typical of the species on NBY (b). Presence of other coryneform plant pathogens, for example Curtobacterium flaccumfaciens pv. flaccumfaciens, can accompany C. nebraskensis in the maize phyllosphere, interfering with accurate isolation and identification of the Goss's wilt pathogen (c,d)