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 blight
HOST: Lilac
Blighted twig with shriveled leaves and dark brown streaks on stem.
Bacterial blight | Lilac
DISEASE: Bacterial blight
HOST: Lilac (Syringa vulgaris)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: S. Thomson
DISEASE: Bacterial blight
HOST: Lilac
Lilac with blighted twigs.
Bacterial blight | Lilac
DISEASE: Bacterial blight
HOST: Lilac (Syringa vulgaris)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: W. Sinclair
DISEASE: Bacterial leaf spot
HOST: Citrus (sp. unknown)
Leaf with flat, spreading lesions.
Bacterial leaf spot | Citrus (sp. unknown)
DISEASE: Bacterial leaf spot
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Xanthomonas alfalfae subsp. citrumelonis
PATHOGEN SYNONYM: Xanthomonas alfalfae subsp. citrumelo
SOURCE: J. H. Graham
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 (sp. unknown)
Fruit with brown, corky lesions.
Citrus canker | Citrus (sp. unknown)
DISEASE: Citrus canker
HOST: Citrus (sp. unknown) (Citrus natsudaidai)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: M. Goto
DISEASE: Citrus canker
HOST: Citrus (sp. unknown)
Fruit with erumpent, corky lesions with collapsed centers surrounded by blackish halos.
Citrus canker | Citrus (sp. unknown)
DISEASE: Citrus canker
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: J. Young
DISEASE: Citrus canker
HOST: Citrus (sp. unknown)
Leaf with corky lesions. Note absence of halos.
Citrus canker | Citrus (sp. unknown)
DISEASE: Citrus canker
HOST: Citrus (sp. unknown) (Citrus natsudaidai)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: M. Goto
DISEASE: Citrus canker
HOST: Citrus (sp. unknown)
Twig with corky lesions.
Citrus canker | Citrus (sp. unknown)
DISEASE: Citrus canker
HOST: Citrus (sp. unknown) (Citrus natsudaidai)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: M. Goto