DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.
Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Sweet potato scab
HOST: Sweet potato
Tubers with large, dark scabs.
Sweet potato scab | Sweet potato
DISEASE: Sweet potato scab
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Streptomyces ipomoeae
SOURCE: APS
DISEASE: Sweet potato scab
HOST: Sweet potato
Black and necrotic decay of fibrous roots.
Sweet potato scab | Sweet potato
DISEASE: Sweet potato scab
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Streptomyces ipomoeae
SOURCE: W. Martin
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