DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown)
Citrus psyllid nymph, a vector of 'Candidatus Liberibacter asiaticus', the cause of citrus greening.

Citrus greening (Huanglongbing) | Citrus (sp. unknown)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: C. Hirayama
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 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: 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