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
DISEASE: Bacterial wilt
HOST: Geranium
Cross section of wilted geranium with infected vascular tissues and bacterial ooze.

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

Bacterial wilt | Geranium
DISEASE: Bacterial wilt
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Daughtrey
DISEASE: Bacterial wilt
HOST: Geranium
Rot and browning of diseased stems.

Bacterial wilt | Geranium
DISEASE: Bacterial wilt
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Daughtrey
DISEASE: Crown gall
HOST: Dahlia
Crown gall of dahlia tubers. Note brownish, rough-surfaced galls, one of which shows rot. Galls often are infected by microorganisms that cause rot.

Crown gall | Dahlia
DISEASE: Crown gall
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: M. Shurtleff
DISEASE: Pith necrosis
HOST: Geranium
Geranium with wilted, yellow necrotic leaves.

Pith necrosis | Geranium
DISEASE: Pith necrosis
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Pith necrosis
HOST: Geranium
Pitted and hollow stems, one of the disease symptoms.

Pith necrosis | Geranium
DISEASE: Pith necrosis
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Magyarosy, D. Thomas