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 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 stem and root rot
HOST: Sweet potato
Collapse of stems and roots caused by systemic activity of the pathogen.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and collapse of stem, petioles, and leaves caused by systemic infection.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and internal discoloration of tuber.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: C. Clark
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