DISEASE: Varnish spot
HOST: Lettuce
Leaf with large brown and small, shiny, dark brown necrotic spots that spread in size and later dry out.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: S. Miller
DISEASE: Varnish spot
HOST: Lettuce
Advanced stage of disease with large, brown necrotic areas. They most often are along veins. Outermost leaves of the head usually are not affected.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: K. Ohata, M. Goto
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
DISEASE: Yellow wilt
HOST: Beet
Symptoms of this disease are yellow leaves, wilting, and then collapse. There may be dwarfing of new leaves, yellowing of sectors, and chlorosis of veins.
Yellow wilt | Beet
DISEASE: Yellow wilt
HOST: Beet (Beta vulgaris)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: F. Hills
DISEASE: Yellow wilt
HOST: Beet
Yellowing and dwarfing of sugar beet (left), an early stage of disease.
Yellow wilt | Beet
DISEASE: Yellow wilt
HOST: Beet (Beta vulgaris)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: J. McFarlane