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: Aster yellows
HOST: Wheat
Healthy head (left) and diseased head (right). Diseased seedlings may die within 2 to 3 weeks. Infected heads of surviving plants are small and sterile, with distorted awns.

Aster yellows | Wheat
DISEASE: Aster yellows
HOST: Wheat (Triticum aestivum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. N. Chiykowski
DISEASE: Bacterial canker and blast
HOST: Apricot
Apricot with typical reddish brown-discolored tissues beneath the bark and gumming around infected areas.

Bacterial canker and blast | Apricot
DISEASE: Bacterial canker and blast
HOST: Apricot (Prunus armeniaca)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: S. Sampson, M. Shurtleff
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 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