DISEASE: Aster yellows
HOST: Watercress
Diseased watercress (left) and healthy plant (right).

Aster yellows | Watercress
DISEASE: Aster yellows
HOST: Watercress (Nasturtium officinale)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Borth
DISEASE: Bacterial leaf spot
HOST: Laurel (California laurel)
Leaf with dark brown, angular spots.

Bacterial leaf spot | Laurel (California laurel)
DISEASE: Bacterial leaf spot
HOST: Laurel (California laurel) (Umbellularia californica)
PATHOGEN: Pseudomonas sp.
PATHOGEN SYNONYM: Pseudomonas lauracearum
SOURCE: W. Sinclair
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish)
Longitudinal sections of diseased rhizomes with discolored vascular tissues.

Bacterial soft rot | Wasabi (Japanese horseradish)
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish) (Wasabia japonica)
PATHOGEN: Pectobacterium wasabiae
PATHOGEN SYNONYM: Erwinia carotovora subsp. wasabiae
SOURCE: M. Goto
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish)
Longitudinal section of rhizome with discolored vascular bundles (left), and rhizome with external symptoms (right).

Bacterial soft rot | Wasabi (Japanese horseradish)
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish) (Wasabia japonica)
PATHOGEN: Pectobacterium wasabiae
PATHOGEN SYNONYM: Erwinia carotovora subsp. wasabiae
SOURCE: M. Goto
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish)
Cross section of rhizome with dark, infected vascular bundles.

Bacterial soft rot | Wasabi (Japanese horseradish)
DISEASE: Bacterial soft rot
HOST: Wasabi (Japanese horseradish) (Wasabia japonica)
PATHOGEN: Pectobacterium wasabiae
PATHOGEN SYNONYM: Erwinia carotovora subsp. wasabiae
SOURCE: G. Rodriguez