DISEASE: Brown blotch
HOST: Mushroom
Stunted fruit bodies, initial stage of disease.

Brown blotch | Mushroom
DISEASE: Brown blotch
HOST: Mushroom (Pleurotus ostreatus)
PATHOGEN: Pseudomonas tolaasii
SOURCE: K. Suyama, M. Goto
DISEASE: Brown blotch
HOST: Mushroom
Fruit bodies at advanced stage of disease.

Brown blotch | Mushroom
DISEASE: Brown blotch
HOST: Mushroom (Pleurotus ostreatus)
PATHOGEN: Pseudomonas tolaasii
SOURCE: K. Suyama, M. Goto
DISEASE: Brown blotch
HOST: Mushroom
Black discoloration of basal portions of fruit bodies. Healthy (left).

Brown blotch | Mushroom
DISEASE: Brown blotch
HOST: Mushroom (Flammulina velutipes)
PATHOGEN: Pseudomonas tolaasii
SOURCE: K. Suyama, M. Goto
DISEASE: Brown blotch
HOST: Mushroom
Black discoloration of basal portion of fruit bodies.

Brown blotch | Mushroom
DISEASE: Brown blotch
HOST: Mushroom (Flammulina velutipes)
PATHOGEN: Pseudomonas tolaasii
SOURCE: K. Suyama, M. Goto
DISEASE: Brown blotch
HOST: Mushroom
Mushrooms with rotted, brownish discoloration of infected areas.

Brown blotch | Mushroom
DISEASE: Brown blotch
HOST: Mushroom (Agaricus campestris)
PATHOGEN: Pseudomonas tolaasii
SOURCE: J. Young
DISEASE: Hollow stalk
HOST: Tobacco
Hollow stalk may appear at time of topping and suckering. Top leaves wilt and the stalk becomes bare as the disease moves downward.

Hollow stalk | Tobacco
DISEASE: Hollow stalk
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: P. Shoemaker
DISEASE: Hollow stalk
HOST: Tobacco
Infection of flue-cured tobacco stalks occur at wound sites caused by topping. After top infection, browning of pith occurs and tissues rot.

Hollow stalk | Tobacco
DISEASE: Hollow stalk
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: APS
DISEASE: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).

Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe