DISEASE: Aster yellows
HOST: Potato
Chlorotic and stunted foliage with necrotic leaf margins. Other symptoms may be phyllody, virescence, purple or yellow pigmentation, and rolling of leaflets.

Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Stunted, chlorotic plants (left) with stiff, rolled leaves.

Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Diseased plant with malformed tubers.

Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon)
The term "black pit" refers to black lesions on fruit, which may be specks or large, sunken pits as seen here. They also may be light tan, later becoming reddish brown to black.

Bacterial blast and black pit | Citrus (Lemon)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Menge
DISEASE: Bacterial gall
HOST: Carrot
Root with many galls of different sizes.

Bacterial gall | Carrot
DISEASE: Bacterial gall
HOST: Carrot (Daucus carota)
PATHOGEN: Rhizobacter dauci
SOURCE: H. Kuwata
DISEASE: Bacterial gall
HOST: Carrot
Galls caused from inoculation of injured roots (left two) and uninjured roots (center two). Uninjured, noninoculated root (right).

Bacterial gall | Carrot
DISEASE: Bacterial gall
HOST: Carrot (Daucus carota)
PATHOGEN: Rhizobacter dauci
SOURCE: M. Goto
DISEASE: Bacterial leaf blight
HOST: Carrot
Blight of flower parts.

Bacterial leaf blight | Carrot
DISEASE: Bacterial leaf blight
HOST: Carrot (Daucus carota)
PATHOGEN: Xanthomonas hortorum pv. carotae
PATHOGEN SYNONYM: Xanthomonas campestris pv. carotae
SOURCE: N. Schaad
DISEASE: Bacterial leaf blight
HOST: Carrot
Leaf lesions begin as water-soaked spots that progress to small, yellow, angular spots and later expand to necrotic lesions with yellow halos.

Bacterial leaf blight | Carrot
DISEASE: Bacterial leaf blight
HOST: Carrot (Daucus carota)
PATHOGEN: Xanthomonas hortorum pv. carotae
PATHOGEN SYNONYM: Xanthomonas campestris pv. carotae
SOURCE: N. Schaad
DISEASE: Bacterial leaf blight
HOST: Carrot
Bacterial ooze on flower stalk from systemic invasion of the pathogen.

Bacterial leaf blight | Carrot
DISEASE: Bacterial leaf blight
HOST: Carrot (Daucus carota)
PATHOGEN: Xanthomonas hortorum pv. carotae
PATHOGEN SYNONYM: Xanthomonas campestris pv. carotae
SOURCE: APS