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 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: Bunch disease
HOST: Walnut
Twisted shoot with yellow leaves, a symptom of bunch disease.

Bunch disease | Walnut
DISEASE: Bunch disease
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: E. Braun
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from longitudinal cracks in the trunk. Cankers are deep extending into wood.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from cracks in trunk, a result of systemic invasion by the bacterium.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale