DISEASE: Coffee leaf scorch
HOST: Coffee
Diseased twig with yellowish, stunted leaves (left). Healthy twig with normal-sized leaves (right).

Coffee leaf scorch | Coffee
DISEASE: Coffee leaf scorch
HOST: Coffee (Coffea arabica)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
DISEASE: Petal blight
HOST: Orchid
Flower petals of Vanda orchid with necrotic spots.

Petal blight | Orchid
DISEASE: Petal blight
HOST: Orchid (Vanda sp.)
PATHOGEN: Acidovorax cattleyae
SOURCE: A. Alvarez
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