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: Western wetwood
HOST: Elm
Spokelike, discolored extensions that expanded into sapwood, following an injection with a fungicide. The causal agent is not known but symptoms are associated with bacteria and yeast.
Western wetwood | Elm
DISEASE: Western wetwood
HOST: Elm (Ulmus americana)
PATHOGEN: Causal agent unknown
SOURCE: W. Sinclair
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