DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.

Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Bacterial canker and blast
HOST: Apricot
Young infected twig with droplets of bacterial ooze on stem.

Bacterial canker and blast | Apricot
DISEASE: Bacterial canker and blast
HOST: Apricot (Prunus armeniaca 'Moorpark')
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Young
DISEASE: Bacterial canker and blast
HOST: Apricot
Bacterial canker has many symptoms. Typical symptoms are brown, sometimes reddish brown, internal tissues and rough, cracked bark.

Bacterial canker and blast | Apricot
DISEASE: Bacterial canker and blast
HOST: Apricot (Prunus armeniaca 'Moorpark')
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Young
DISEASE: Bacterial canker and blast
HOST: Apricot
Infected apricot with sparse foliage (some twigs with no foliage) and a discolored area exposed where bark was removed.

Bacterial canker and blast | Apricot
DISEASE: Bacterial canker and blast
HOST: Apricot (Prunus armeniaca 'Moorpark')
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Young
DISEASE: Bacterial canker and blast
HOST: Apricot
Fruit spot phase with numerous reddish necrotic spots.

Bacterial canker and blast | Apricot
DISEASE: Bacterial canker and blast
HOST: Apricot (Prunus armeniaca 'Moorpark')
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Young
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Coreopsis
Bacterial fasciation of coreopsis.

Bacterial fasciation (Leafy gall) | Coreopsis
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Coreopsis (Coreopsis sp.)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Putnam
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Stems with necrotic lesions.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with brown necrotic spots. Stems have water-soaked spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: S. Thomson