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
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.

Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial canker
HOST: Cherry
Cherry with necrotic internal tissues and external symptoms of ooze (gummosis) caused by systemic infection.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. morsprunorum
SOURCE: D. Funk, A. Alvarez
DISEASE: Bacterial canker
HOST: Cherry
Systemic infection of petioles and leaves.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. morsprunorum
SOURCE: D. Funk, A. Alvarez
DISEASE: Bacterial canker
HOST: Cherry
Blast stage of canker disease affects flowers, buds, and leaves. Necrotic lesions on fruit may cause distortion.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: S. Thomson
DISEASE: Bacterial canker
HOST: Cherry
Cherry petioles with dark necrotic lesions. Premature fruit drop is associated with the disease.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: S. Thomson
DISEASE: Bacterial canker
HOST: Cherry
Cherry petioles with spots, sunken centers, and water-soaked, brown margins.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: S. Thomson