DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.
Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
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 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
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
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin