DISEASE: Blister spot
HOST: Apple
Fruit with water-soaked spots.

Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Blister spot
HOST: Apple
Water-soaked blister spots on leaves of blighted twig.

Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Blister spot
HOST: Apple
Apple with brownish blister spots.

Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica 'Mutsu')
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: S. Thomson
DISEASE: Blister spot
HOST: Apple
Late stage of blister spot. The purplish black lesions are associated with lenticels and stomata.

Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica 'Crispin')
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Wilted, stunted plants with yellowing foliage.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. P. Weingartner
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
External symptoms of the disease.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. Thurston
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Tubers with distinct grayish brown rings and bacterial ooze from vascular tissues.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: A. Hayward
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Young plant (left) with small, numerous stems (witches'-broom). Healthy stems (right).

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson