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 leaf spot
HOST: Alfalfa
Stems with necrotic lesions.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with brown necrotic spots. Stems have water-soaked spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: S. Thomson
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with both water-soaked and necrotic spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with necrotic, brownish paperlike areas.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Bean
Bean leaf with white pustules following inoculation. Stem inoculation causes veinal yellowing and necrosis of leaves. Infected seed may be purple or yellow.

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: L. Claflin
DISEASE: Bacterial wilt
HOST: Bean
Leaves with interveinal chlorosis and necrosis. Healthy (right).

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Bean
Bean seeds infected with orange (upper right), violet (upper left), and yellow (lower left) variants of Curtobacterium flaccumfaciens. White seed in the lower right is healthy.

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS