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: Oak leaf scorch
HOST: Oak
Oak with scorched leaf tips.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus kelloggii)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Kostka
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Oak leaf scorch
HOST: Oak
Diseased tree with brownish, scorched leaves.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Sheath brown rot
HOST: Rice
Disease symptoms typically occur on flag leaf sheaths from booting to heading stage and also on panicles. Water-soaked lesions on glumes turn light brown.

Sheath brown rot | Rice
DISEASE: Sheath brown rot
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia fuscovaginae
PATHOGEN SYNONYM: Pseudomonas fuscovaginae
SOURCE: K. Miyajima, M. Goto
DISEASE: Sheath brown rot
HOST: Rice
Close-up of stem lesions.

Sheath brown rot | Rice
DISEASE: Sheath brown rot
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia fuscovaginae
PATHOGEN SYNONYM: Pseudomonas fuscovaginae
SOURCE: K. Miyajima, M. Goto