DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit)
Leaves with mottled chlorosis.

Australian citrus dieback | Citrus (Grapefruit)
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: P. Broadbent
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit)
Late stage of disease. Note yellowing of leaf veins and entire leaves.

Australian citrus dieback | Citrus (Grapefruit)
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: P. Broadbent
DISEASE: Australian citrus dieback
HOST: Citrus (Lime)
Severe decline, a late stage of disease. The disease spreads slowly in mature trees, progressing faster in young trees.

Australian citrus dieback | Citrus (Lime)
DISEASE: Australian citrus dieback
HOST: Citrus (Lime) (Citrus sp.)
PATHOGEN: 'Candidatus Phytoplasma australiense'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: P. Broadbent
DISEASE: Bacterial blight (Leaf spot)
HOST: Clover
Diseased leaf with elongated, reddish brown lesions, especially numerous on the margins.

Bacterial blight (Leaf spot) | Clover
DISEASE: Bacterial blight (Leaf spot)
HOST: Clover (Trifolium alexandrinum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: M. Shurtleff
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