DISEASE: Bacterial canker
HOST: Hazelnut
Primary symptoms are failure of buds to break and withering and death of new foliage in spring. Dead leaves remain attached to limbs after normal leaf fall.

Bacterial canker | Hazelnut
DISEASE: Bacterial canker
HOST: Hazelnut (Corylus americana)
PATHOGEN: Pseudomonas syringae pv. avellanae
PATHOGEN SYNONYM: Pseudomonas avellanae
SOURCE: P. Psalidas
DISEASE: Bacterial leaf spot
HOST: Cowpea
Leaf spots vary in size from small to large and some fall out in time, leaving a shot-hole appearance.

Bacterial leaf spot | Cowpea
DISEASE: Bacterial leaf spot
HOST: Cowpea (Vigna unguiculata)
PATHOGEN: Xanthomonas axonopodis pv. vignicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. vignicola
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot
HOST: Cowpea
Leaves with large, light brown necrotic areas.

Bacterial leaf spot | Cowpea
DISEASE: Bacterial leaf spot
HOST: Cowpea (Vigna unguiculata)
PATHOGEN: Xanthomonas axonopodis pv. vignicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. vignicola
SOURCE: R. Gitaitis
DISEASE: Bois noir disease
HOST: Grape
Severe symptoms of triangular-trapezoid-shaped leaves with desiccated appearance.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera)
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler
DISEASE: Bois noir disease
HOST: Grape
Leaves with disease symptoms identical to flavescence doree, a yellows disease caused by a different phytoplasma. The latter has a slightly different host range and is transmitted by a leafhopper.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera)
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler
DISEASE: Bois noir disease
HOST: Grape
Bois noir disease may be expressed on one branch while other branches appear healthy. Note trapezoid-shaped leaves.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler
DISEASE: Bois noir disease
HOST: Grape
Typical symptoms of triangular-trapezoid-shaped, greenish yellow leaves.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler
DISEASE: Bois noir disease
HOST: Grape
Berries from infected vines are shrunken and low in sugar and have a high acid content, making them unfit for wine production.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler
DISEASE: Bois noir disease
HOST: Grape
A typical symptom of disease is uneven lignification of infected branches, resulting in a mix of brown and green patches.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler