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 blast and black pit
HOST: Citrus (Lemon)
The term "black pit" refers to black lesions on fruit, which may be specks or large, sunken pits as seen here. They also may be light tan, later becoming reddish brown to black.
Bacterial blast and black pit | Citrus (Lemon)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Menge
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 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
DISEASE: Citrus canker
HOST: Citrus (Lemon)
Lower leaf with raised, corkylike lesions surrounded by dark brown halos, one of the diagnostic symptoms of citrus canker.
Citrus canker | Citrus (Lemon)
DISEASE: Citrus canker
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: T. Gottwald