DISEASE: Aster yellows
HOST: Squash
Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.

Aster yellows | Squash
DISEASE: Aster yellows
HOST: Squash (Cucurbita sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Miller
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: Bacterial spot
HOST: Pepper
Leaves with necrotic spots. The bacterial spot xanthomonads are Xanthomonas euvesicatoria, X. vesicatoria, and X. gardneri.

Bacterial spot | Pepper
DISEASE: Bacterial spot
HOST: Pepper (Capsicum annuum)
PATHOGEN: Xanthomonas bacterial spot pathogens
PATHOGEN SYNONYM: Xanthomonas axonopodis pv. vesicatoria
SOURCE: APS
DISEASE: Bacterial spot
HOST: Pepper
Leaves with water-soaked and brown necrotic lesions. Disease xanthomonads are Xanthomonas euvesicatoria, X. vesicatoria, and X. gardneri.

Bacterial spot | Pepper
DISEASE: Bacterial spot
HOST: Pepper (Capsicum annuum)
PATHOGEN: Xanthomonas bacterial spot pathogens
PATHOGEN SYNONYM: Xanthomonas axonopodis pv. vesicatoria
SOURCE: B. S. Kim
DISEASE: Bacterial spot
HOST: Pepper
Leaves with broad necrotic lesions. Disease xanthomonads are Xanthomonas euvesicatoria, X. vesicatoria, and X. gardneri.

Bacterial spot | Pepper
DISEASE: Bacterial spot
HOST: Pepper (Capsicum annuum)
PATHOGEN: Xanthomonas bacterial spot pathogens
PATHOGEN SYNONYM: Xanthomonas axonopodis pv. vesicatoria
SOURCE: J. Jones
DISEASE: Bacterial spot
HOST: Pepper
Infected fruit with brown, wartlike lesions. The bacterial spot xanthomonads are Xanthomonas euvesicatoria, X. vesicatoria, and X. gardneri.

Bacterial spot | Pepper
DISEASE: Bacterial spot
HOST: Pepper (Capsicum annuum)
PATHOGEN: Xanthomonas bacterial spot pathogens
PATHOGEN SYNONYM: Xanthomonas axonopodis pv. vesicatoria
SOURCE: A. Alvarez
DISEASE: Bacterial spot
HOST: Pepper
Close-up of fruit with enlarged lesions with cracked, roughened, wartlike appearance. Disease xanthomonads are Xanthomonas euvesicatoria, X. vesicatoria, and X. gardneri.

Bacterial spot | Pepper
DISEASE: Bacterial spot
HOST: Pepper (Capsicum annuum)
PATHOGEN: Xanthomonas bacterial spot pathogens
PATHOGEN SYNONYM: Xanthomonas axonopodis pv. vesicatoria
SOURCE: APS
DISEASE: Bacterial stripe (Blight)
HOST: Oat
Leaves with irregular necrotic spots and elongated stripes that are light tan in the center. Symptoms begin as water-soaked lesions.

Bacterial stripe (Blight) | Oat
DISEASE: Bacterial stripe (Blight)
HOST: Oat (Avena sativa)
PATHOGEN: Pseudomonas syringae pv. striafaciens
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Squash
Field with severe symptoms of wilt. Foliage often is chlorotic and leaf margins may be chlorotic and necrotic before plant death. Bacterial ooze may be seen streaming from the xylem when infected stems are cut.

Bacterial wilt | Squash
DISEASE: Bacterial wilt
HOST: Squash (Cucurbita maxima)
PATHOGEN: Erwinia tracheiphila
SOURCE: B. Jacobsen, M. Shurtleff