DISEASE: Bacterial leaf spot (Blight)
HOST: Begonia
Initial symptoms appear as small, blisterlike lesions. As lesions age, they enlarge, producing broad patches of necrotic leaf tissue.

Bacterial leaf spot (Blight) | Begonia
DISEASE: Bacterial leaf spot (Blight)
HOST: Begonia (Begonia sp.)
PATHOGEN: Xanthomonas axonopodis pv. begoniae
PATHOGEN SYNONYM: Xanthomonas campestris pv. begoniae
SOURCE: APS
DISEASE: Bacterial leaf spot (Blight)
HOST: Begonia
Advanced stage of disease with dark, large necrotic areas on leaves and interveinal chlorosis.

Bacterial leaf spot (Blight) | Begonia
DISEASE: Bacterial leaf spot (Blight)
HOST: Begonia (Begonia sp.)
PATHOGEN: Xanthomonas axonopodis pv. begoniae
PATHOGEN SYNONYM: Xanthomonas campestris pv. begoniae
SOURCE: APS
DISEASE: Bacterial leaf streak
HOST: Oat
Leaf with long, dark red streaks.

Bacterial leaf streak | Oat
DISEASE: Bacterial leaf streak
HOST: Oat (Avena sativa)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: L. Claflin
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Lesions on leaves first appear as water-soaked, translucent, long, narrow streaks. They later turn brown and necrotic and often coalesce into blighted areas.

Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Close-up of leaf with brown necrotic streaks.

Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: Halo blight
HOST: Bean
Chlorotic, systemic symptoms with necrotic lesions on leaves of 'Romano' common bean.

Halo blight | Bean
DISEASE: Halo blight
HOST: Bean (Phaseolus vulgaris 'Romano')
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: M. Schroth
DISEASE: Halo blight
HOST: Bean
Leaf of 'Bountiful' bean with chlorotic halos, an early stage of disease. Tiny water-soaked are difficult to see.

Halo blight | Bean
DISEASE: Halo blight
HOST: Bean (Phaseolus vulgaris 'Bountiful')
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: M. Schroth
DISEASE: Halo blight
HOST: Bean
Common bean with systemic chlorosis and distorted leaves.

Halo blight | Bean
DISEASE: Halo blight
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: A. Hayward
DISEASE: Halo blight
HOST: Bean
Leaves of highly susceptible 'Red Kidney' dry bean with typical water-soaked lesions with halos.

Halo blight | Bean
DISEASE: Halo blight
HOST: Bean (Phaseolus vulgaris 'Red Kidney')
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: M. Goto