DISEASE: Apple proliferation
HOST: Apple
Spring form of the adult black-veined psyllid, Cacopsylla melanoneura, a vector of apple proliferation. In winter, adults are more greenish in color.

Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Apple proliferation
HOST: Apple
Typical apple proliferation symptom of witches'-broom resulting from suppression of apical dominance and growth of dormant axillary buds. Branches are not usually bent down as shown here.

Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Bacterial blight (Brown stem)
HOST: Celery
Lesions are necrotic and circular to angular. Some have yellowish halos. Older lesions become brown and dry.

Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raid
DISEASE: Bacterial blight (Brown stem)
HOST: Celery
Ooze from lesion on celery leaf.

Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raid
DISEASE: Bacterial blight (Brown stem)
HOST: Celery
Characteristic brown discoloration of petioles, which is more evident on inside of petiole close to the crown. Parenchyma tissues are firm and brown.

Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: K. Pernezny
DISEASE: Bacterial leaf spot
HOST: Cabbage
Necrotic, light tan leaf spots, a late stage in disease development.

Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica pekinensis)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell
DISEASE: Bacterial leaf spot
HOST: Celery
Leaves with typical symptoms of rusty brown lesions with greasy appearance.

Bacterial leaf spot | Celery
DISEASE: Bacterial leaf spot
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas syringae pv. apii
SOURCE: R. Gilbertson
DISEASE: Bacterial leaf spot
HOST: Celery
Celery leaves with rusty brown lesions and some yellowing at leaf tips.

Bacterial leaf spot | Celery
DISEASE: Bacterial leaf spot
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas syringae pv. apii
SOURCE: S. Koike