DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.

Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
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: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: X-disease (Eastern X)
HOST: Chokecherry
Shot-hole stage of X-disease.

X-disease (Eastern X) | Chokecherry
DISEASE: X-disease (Eastern X)
HOST: Chokecherry (Prunus virginiana)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair
DISEASE: X-disease (Eastern X)
HOST: Chokecherry
X-disease causes rosettes and premature loss of leaves.

X-disease (Eastern X) | Chokecherry
DISEASE: X-disease (Eastern X)
HOST: Chokecherry (Prunus virginiana)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair
DISEASE: X-disease (Eastern X)
HOST: Chokecherry
Chokecherry with stunted shoots, red leaves, and rosettes.

X-disease (Eastern X) | Chokecherry
DISEASE: X-disease (Eastern X)
HOST: Chokecherry (Prunus virginiana)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair
DISEASE: X-disease (Eastern X)
HOST: Chokecherry
Chokecherry with red leaves, rosettes, and bud loss.

X-disease (Eastern X) | Chokecherry
DISEASE: X-disease (Eastern X)
HOST: Chokecherry (Prunus virginiana)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair