DISEASE: Bacterial leaf spot and blight
HOST: Parsley
Blighted leaves with large, brown necrotic areas.

Bacterial leaf spot and blight | Parsley
DISEASE: Bacterial leaf spot and blight
HOST: Parsley (Petroselinum crispum)
PATHOGEN: Pseudomonas syringae pv. apii
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Celery
Leaves with typical symptoms of rusty brown lesions with greasy appearance.

Bacterial leaf spot | Celery
DISEASE: Bacterial leaf spot
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas syringae pv. apii
SOURCE: R. Gilbertson
DISEASE: Bacterial leaf spot
HOST: Celery
Celery leaves with rusty brown lesions and some yellowing at leaf tips.

Bacterial leaf spot | Celery
DISEASE: Bacterial leaf spot
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas syringae pv. apii
SOURCE: S. Koike
DISEASE: Corky root
HOST: Lettuce
Corky root causes a reduction in size of lettuce heads and root systems; susceptible cultivar (right) and resistant cultivar (left).

Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: E. J. Ryder
DISEASE: Corky root
HOST: Lettuce
Close-up of root with malformed, corky appearance and longitudinal ridges of brown tissues.

Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: A. van Bruggen
DISEASE: Corky root
HOST: Lettuce
Initial symptoms of disease are yellow lesions on taproot and main laterals. Greenish brown bands occur around roots. Root pith may become brown and hollow.

Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: A. van Bruggen
DISEASE: Corky root
HOST: Lettuce
Differences in corky root symptoms between susceptible cultivar (right) and resistant cultivar (left).

Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: E. Ryder
DISEASE: Multiplier disease
HOST: Strawberry
Multiplier disease causes production of numerous crowns along runners.

Multiplier disease | Strawberry
DISEASE: Multiplier disease
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: M. Clark
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson