DISEASE: Aster yellows
HOST: Barley
Infection by this phytoplasm causes twisted awns and sterile florets.
Aster yellows | Barley
DISEASE: Aster yellows
HOST: Barley (Hordeum vulgare)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: E. Banttari
DISEASE: Aster yellows
HOST: Barley
Small necrotic spots on lower leaves and red coalescing streaks on upper leaves.
Aster yellows | Barley
DISEASE: Aster yellows
HOST: Barley (Hordeum vulgare)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: E. Banttari
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 fruit blotch
HOST: Cantaloupe
Early stage of disease with discolored blotches on the surface.
Bacterial fruit blotch | Cantaloupe
DISEASE: Bacterial fruit blotch
HOST: Cantaloupe (Cucumis melo var. cantalupensis)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: D. B. Langston
DISEASE: Bacterial fruit blotch
HOST: Cantaloupe
View of disease path from rind to internal rotting of melon.
Bacterial fruit blotch | Cantaloupe
DISEASE: Bacterial fruit blotch
HOST: Cantaloupe (Cucumis melo var. cantalupensis)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial fruit blotch
HOST: Cantaloupe
Leaf spot stage. Lesions start small and may coalesce, forming large, brown necrotic areas.
Bacterial fruit blotch | Cantaloupe
DISEASE: Bacterial fruit blotch
HOST: Cantaloupe (Cucumis melo var. cantalupensis)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: D. B. Langston
DISEASE: Bacterial kernel blight (Leaf blight)
HOST: Barley
Dark, brown discolored kernels at the embryo end and posterior surface.
Bacterial kernel blight (Leaf blight) | Barley
DISEASE: Bacterial kernel blight (Leaf blight)
HOST: Barley (Hordeum vulgare)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: C. Martinez-Miller
DISEASE: Bacterial leaf blight
HOST: Barley
Diseased barley plants with typical bleaching of flag leaves. Initial symptoms are water-soaked lesions that later coalesce. Eventually, the entire leaf becomes necrotic and edges roll inward.
Bacterial leaf blight | Barley
DISEASE: Bacterial leaf blight
HOST: Barley (Hordeum vulgare)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: D. Sands
DISEASE: Bacterial wilt
HOST: Cantaloupe
Cantaloupe field with severe destruction from bacterial wilt (left), less on right.
Bacterial wilt | Cantaloupe
DISEASE: Bacterial wilt
HOST: Cantaloupe (Cucumis melo var. cantalupensis)
PATHOGEN: Erwinia tracheiphila
SOURCE: L. Claflin