DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.

Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
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
DISEASE: Bacterial wilt
HOST: Grass
Initial symptom is a lime-green, yellow, or blue-green appearance of the grass. The next symptom is small, reddish brown spots on leaf blades.

Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: P. H. Dernoeden
DISEASE: Bacterial wilt
HOST: Grass
Infected turf grass with patches of yellowing, wilted, and dead grass.

Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Grass
Late stage of disease development. Dead grass has a light brown or bleached tan appearance.

Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: P. H. Dernoeden
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin