DISEASE: Bacterial wilt and dieback
HOST: Willow
Cross sections of the characteristic "watermark stain" of diseased wood. Wilt and dieback occur as disease progresses.

Bacterial wilt and dieback | Willow
DISEASE: Bacterial wilt and dieback
HOST: Willow (Salix sp.)
PATHOGEN: Brenneria salicis
PATHOGEN SYNONYM: Erwinia salicis
SOURCE: Y. Sakamoto, M. Goto
DISEASE: Bacterial wilt and dieback
HOST: Willow
Severely diseased tree with dieback symptoms.

Bacterial wilt and dieback | Willow
DISEASE: Bacterial wilt and dieback
HOST: Willow (Salix sp.)
PATHOGEN: Brenneria salicis
PATHOGEN SYNONYM: Erwinia salicis
SOURCE: Y. Sakamoto, M. Goto
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 variegated chlorosis
HOST: Citrus (sp. unknown)
Leaf with chlorosis in interveinal spaces and brown spots visible on lower leaf surface.

Citrus variegated chlorosis | Citrus (sp. unknown)
DISEASE: Citrus variegated chlorosis
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Xylella fastidiosa
SOURCE: M. J. G. Beretta
DISEASE: Citrus variegated chlorosis
HOST: Citrus (sp. unknown)
Interveinal chlorosis on upper side of leaves.

Citrus variegated chlorosis | Citrus (sp. unknown)
DISEASE: Citrus variegated chlorosis
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Xylella fastidiosa
SOURCE: M. J. G. Beretta
DISEASE: Citrus variegated chlorosis
HOST: Citrus (sp. unknown)
Leafhopper (Oncometopia nigricans) vector of Xylella fastidiosa, which transmits citrus variegated chlorosis.

Citrus variegated chlorosis | Citrus (sp. unknown)
DISEASE: Citrus variegated chlorosis
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: Xylella fastidiosa
SOURCE: D. Hopkins
DISEASE: Citrus variegated chlorosis
HOST: Citrus (Orange)
Small, hard, diseased fruit interspersed with three normal fruits for comparison. Diseased fruit often exhibit sunburn symptoms.

Citrus variegated chlorosis | Citrus (Orange)
DISEASE: Citrus variegated chlorosis
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: M. J. G. Beretta