DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia
Blighted leaves and stems.

Bacterial leaf spot (Blight) | Poinsettia
DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia (Euphorbia pulcherrima)
PATHOGEN: Curtobacterium flaccumfaciens pv. poinsettiae
SOURCE: APS
DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia
Poinsettia with diseased stem. Woody stems may have a yellowed cortex and dark vascular tissues. The stem tip may curve with deformed terminal leaves.

Bacterial leaf spot (Blight) | Poinsettia
DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia (Euphorbia pulcherrima)
PATHOGEN: Curtobacterium flaccumfaciens pv. poinsettiae
SOURCE: APS
DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia
Leaves with small, dark spots, an early stage of disease.

Bacterial leaf spot (Blight) | Poinsettia
DISEASE: Bacterial leaf spot (Blight)
HOST: Poinsettia (Euphorbia pulcherrima)
PATHOGEN: Curtobacterium flaccumfaciens pv. poinsettiae
SOURCE: A. Alvarez
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: Ear rot
HOST: Corn (Maize)
Rot at apical end of ear.

Ear rot | Corn (Maize)
DISEASE: Ear rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky
DISEASE: Marginal leaf blight
HOST: Lettuce
Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.

Marginal leaf blight | Lettuce
DISEASE: Marginal leaf blight
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky