DISEASE: Bacterial leaf spot
HOST: Larkspur
Infected leaflets with many purplish spots with necrotic centers.
Bacterial leaf spot | Larkspur
DISEASE: Bacterial leaf spot
HOST: Larkspur (Delphinium sp.)
PATHOGEN: Pseudomonas syringae pv. delphinii
SOURCE: R. Raabe
DISEASE: Bacterial wilt
HOST: Alfalfa
Longitudinal section of defined brown gum pockets on inner surface of root bark.
Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Infected plant (left) with typical symptoms of stunting and chlorosis. Other characteristic symptoms are spindly stems and small distorted leaflets. Healthy plant (right).
Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Diseased plant with chlorotic leaves.
Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Cross sections of diseased roots with defined brown gum pockets on inner surface of bark. Healthy root (upper left). Other sections represent increases in disease severity.
Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: L. Claflin
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: Bacterial wilt
HOST: Muskmelon
Severely diseased plants as noted by dying runners.
Bacterial wilt | Muskmelon
DISEASE: Bacterial wilt
HOST: Muskmelon (Cucumis melo)
PATHOGEN: Erwinia tracheiphila
SOURCE: M. Shurtleff
DISEASE: Bacterial wilt
HOST: Muskmelon
Wilt-devastated muskmelon field.
Bacterial wilt | Muskmelon
DISEASE: Bacterial wilt
HOST: Muskmelon (Cucumis melo)
PATHOGEN: Erwinia tracheiphila
SOURCE: M. Shurtleff
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