DISEASE: Bacterial leaf scorch
HOST: Pecan
Pecan with necrotic scorched leaves with distinct dark lines between healthy and diseased tissues.

Bacterial leaf scorch | Pecan
DISEASE: Bacterial leaf scorch
HOST: Pecan (Carya illinoinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: T. Brenneman
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Sycamore with scorched leaves and dieback of small branches.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Close-up of scorched leaves.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
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 stubborn disease
HOST: Citrus (Orange)
Severely stunted sweet orange tree. Foliage is dense and abnormally upright. Leaves may be cupped and unusually thick. They also may be chlorotic and mottled.

Citrus stubborn disease | Citrus (Orange)
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Spiroplasma citri
SOURCE: S. M. Garnsey
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange)
Fruit from a diseased tree are frequently lopsided or acorn-shaped, usually few and small. They may not color at stem end.

Citrus stubborn disease | Citrus (Orange)
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Spiroplasma citri
SOURCE: J. M. Bove, M. Garnier
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange)
Sweet orange exhibiting off-season flowering and crop heterogeneity. Diseased trees generally have shoots with shortened internodes, which lead to rosettes with cupped leaves.

Citrus stubborn disease | Citrus (Orange)
DISEASE: Citrus stubborn disease
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: Spiroplasma citri
SOURCE: J. M. Bove, M. Garnier
DISEASE: Wildfire (Angular leaf spot)
HOST: Tobacco
Characteristic symptoms are necrotic, brown spots with angular margins surrounded by distinct yellow halos. The halos are caused by the production of tabtoxin.

Wildfire (Angular leaf spot) | Tobacco
DISEASE: Wildfire (Angular leaf spot)
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pseudomonas syringae pv. tabaci
SOURCE: G. Lucas