DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.
Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
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: Oleander leaf scorch
HOST: Oleander
Diseased plant with scalloped, yellowish leaves. This usually is followed by dieback of twigs and branches. Plants often die 2 years after infection.
Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
DISEASE: Oleander leaf scorch
HOST: Oleander
Oleander with symptoms of severe scorch.
Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: M. Blua
DISEASE: Oleander leaf scorch
HOST: Oleander
Oleander with scorch symptoms primarily at leaf tips, an early stage of disease.
Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: M. Blua