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 brown spot
HOST: Mallotus
Leaf with small, rustylike lesions.

Bacterial brown spot | Mallotus
DISEASE: Bacterial brown spot
HOST: Mallotus (Mallotus japonicus)
PATHOGEN: Xanthomonas campestris pv. malloti
SOURCE: M. Goto
DISEASE: Bacterial brown spot
HOST: Mallotus
Leaf with tiny, light brown spots surrounded by chlorotic zones.

Bacterial brown spot | Mallotus
DISEASE: Bacterial brown spot
HOST: Mallotus (Mallotus japonicus)
PATHOGEN: Xanthomonas campestris pv. malloti
SOURCE: M. Kobayashi, M. Goto
DISEASE: Bacterial canker
HOST: Tomato
Necrosis of leaf margins is early symptom of disease.

Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: S. Miller
DISEASE: Bacterial canker
HOST: Tomato
Leaves with interveinal necrosis.

Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: D. Ingram
DISEASE: Bacterial canker
HOST: Tomato
Leaves with papery, gray necrotic areas around green veins.

Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: D. Ingram
DISEASE: Bacterial canker
HOST: Tomato
Sliced stem with yellowish brown discoloration of vascular tissues.

Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: S. Miller
DISEASE: Bacterial canker
HOST: Tomato
Advanced stage of disease with reddish brown discoloration of vascular tissues (bottom). Healthy stem (top).

Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: D. Ingram