DISEASE: Bacterial hyperplastic canker
HOST: Almond
Diseased tree with multiple cankers. Margins of cankers are rough, soft, cheesy, dark brown, and have scalloped water-soaked spots that turn brown. Multiple cankers may girdle and kill small twigs.

Bacterial hyperplastic canker | Almond
DISEASE: Bacterial hyperplastic canker
HOST: Almond (Prunus dulcis)
PATHOGEN: Pseudomonas amygdali
SOURCE: P. Psallidas
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 leaf spot
HOST: Peanut
The disease causes water-soaked lesions, particularly on upper leaf surfaces. Lesions enlarge and later display brown necrotic areas. Leaflets become chlorotic and shed prematurely.

Bacterial leaf spot | Peanut
DISEASE: Bacterial leaf spot
HOST: Peanut (Arachis hypogaea)
PATHOGEN: Pseudomonas sp.
SOURCE: P. Subrahmanyam
DISEASE: Bacterial leaf spot
HOST: Verbena
Leaf with purple-brown necrotic spots.

Bacterial leaf spot | Verbena
DISEASE: Bacterial leaf spot
HOST: Verbena (Verbena sp.)
PATHOGEN: Pseudomonas sp.
SOURCE: R. Raabe
DISEASE: Brittle root
HOST: Horseradish
Dying, stunted, yellow to brown horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: C. Eastman, M. Davis
DISEASE: Brittle root
HOST: Horseradish
Close-up of stunted, yellow horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: D. Sherrod
DISEASE: Brittle root
HOST: Horseradish
Horseradish with discolored internal tissues. Healthy root segment (top right).

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: J. Fletcher, M. Davis
DISEASE: Citrus stubborn disease
HOST: Citrus (sp. unknown)
Characteristic symptoms of thickened peel at peduncle end and aborted seeds.

Citrus stubborn disease | Citrus (sp. unknown)
DISEASE: Citrus stubborn disease
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Spiroplasma citri
SOURCE: APS
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange)
Severely stunted sweet orange tree. Foliage is dense and abnormally upright. Leaves may be cupped and unusually thick. They also may be chlorotic and mottled.

Citrus stubborn disease | Citrus (Orange)
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Spiroplasma citri
SOURCE: S. M. Garnsey