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: Brittle root
HOST: Horseradish
Dying, stunted, yellow to brown horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: C. Eastman, M. Davis
DISEASE: Brittle root
HOST: Horseradish
Close-up of stunted, yellow horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: D. Sherrod
DISEASE: Brittle root
HOST: Horseradish
Horseradish with discolored internal tissues. Healthy root segment (top right).

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: J. Fletcher, M. Davis
DISEASE: Oak leaf scorch
HOST: Oak
Oak with scorched leaf tips.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus kelloggii)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Kostka
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.

Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair