DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.

Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial canker
HOST: Hazelnut
Primary symptoms are failure of buds to break and withering and death of new foliage in spring. Dead leaves remain attached to limbs after normal leaf fall.

Bacterial canker | Hazelnut
DISEASE: Bacterial canker
HOST: Hazelnut (Corylus americana)
PATHOGEN: Pseudomonas syringae pv. avellanae
PATHOGEN SYNONYM: Pseudomonas avellanae
SOURCE: P. Psalidas
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower
Leaves with tiny lesions surrounded by large halos.

Bacterial leaf spot (Head rot) | Cauliflower
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Pseudomonas syringae pv. maculicola
SOURCE: R. Campbell
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower
Section of a cauliflower head with discolored, infected tissues.

Bacterial leaf spot (Head rot) | Cauliflower
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Pseudomonas syringae pv. maculicola
SOURCE: R. Campbell
DISEASE: Bacterial stalk and top rot
HOST: Corn (Maize)
Corn exhibiting symptoms at early stage of disease. Note water-soaked external stalk tissues.

Bacterial stalk and top rot | Corn (Maize)
DISEASE: Bacterial stalk and top rot
HOST: Corn (Maize) (Zea mays 'Pukekohe')
PATHOGEN: Dickeya zeae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. zeae
SOURCE: J. Young
DISEASE: Black rot
HOST: Cauliflower
Brown, necrotic, rotted areas on flower parts and typical V-shaped necrotic areas on leaf margins.

Black rot | Cauliflower
DISEASE: Black rot
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Xanthomonas campestris pv. campestris
SOURCE: B. Jacobsen, M. Shurtleff