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: 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: 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
DISEASE: Bacterial canker
HOST: Tomato
Lesions on stems and sepals.
Bacterial canker | Tomato
DISEASE: Bacterial canker
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Clavibacter michiganensis subsp. michiganensis
PATHOGEN SYNONYM: Corynebacterium michiganense
SOURCE: S. Miller