DISEASE: Bacterial fasciation (Leafy gall)
HOST: Petunia
Note hyperplasia and leafy galls.

Bacterial fasciation (Leafy gall) | Petunia
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Petunia (Petunia sp.)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Shurtleff
DISEASE: Bacterial leaf spot
HOST: Larkspur
Infected leaflets with many purplish spots with necrotic centers.

Bacterial leaf spot | Larkspur
DISEASE: Bacterial leaf spot
HOST: Larkspur (Delphinium sp.)
PATHOGEN: Pseudomonas syringae pv. delphinii
SOURCE: R. Raabe
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
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair