DISEASE: Bacterial blight
HOST: Geranium
Close-up of upper side of leaf with dark brown spots.

Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
DISEASE: Bacterial blight
HOST: Geranium
Close-up of lower side of leaf with dark brown lesions.

Bacterial blight | Geranium
DISEASE: Bacterial blight
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Xanthomonas hortorum pv. pelargonii
PATHOGEN SYNONYM: Xanthomonas campestris pv. pelargonii
SOURCE: M. Daughtrey
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: 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: Geranium
Disease begins as water-soaked lesions that become brown to black and may coalesce, forming large necrotic areas.

Bacterial leaf spot | Geranium
DISEASE: Bacterial leaf spot
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raabe
DISEASE: Bacterial leaf spot
HOST: Geranium
Leaves with varying degrees of disease severity.

Bacterial leaf spot | Geranium
DISEASE: Bacterial leaf spot
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: APS
DISEASE: Bacterial seed and seedling rot
HOST: Geranium
Cotyledons with water-soaked spots.

Bacterial seed and seedling rot | Geranium
DISEASE: Bacterial seed and seedling rot
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Paenibacillus sp.
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Bacterial seed and seedling rot
HOST: Geranium
Rotted and discolored seeds (right). Healthy seeds (left).

Bacterial seed and seedling rot | Geranium
DISEASE: Bacterial seed and seedling rot
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Paenibacillus sp.
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Bacterial wilt
HOST: Geranium
Necrotic, umbrella-like appearance of infected leaves, an early stage of disease. Lower leaves become yellow and necrosis develops as the disease progresses. V-shaped necrosis is typical of other systemic diseases.

Bacterial wilt | Geranium
DISEASE: Bacterial wilt
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Daughtrey