DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.

Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Almond leaf scorch
HOST: Almond
Light brown necrotic (scorched) areas on curling leaves.

Almond leaf scorch | Almond
DISEASE: Almond leaf scorch
HOST: Almond (Prunus dulcis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Almond leaf scorch
HOST: Almond
Dying almond trees with scorched appearance. Initial symptoms are marginal chlorosis, usually late in the year. Scorch often is first noted at leaf tips, symptoms worsen, and terminal branches may die.

Almond leaf scorch | Almond
DISEASE: Almond leaf scorch
HOST: Almond (Prunus dulcis)
PATHOGEN: Xylella fastidiosa
SOURCE: R. Davis, M. Davis
DISEASE: Bacterial blight
HOST: Parsnip
Parsnip with severe blight symptoms. There also is browning of the vascular system. Rot may progress from the crown into roots.

Bacterial blight | Parsnip
DISEASE: Bacterial blight
HOST: Parsnip (Pastinaca sativa)
PATHOGEN: Pseudomonas viridiflava
SOURCE: J. Hunter
DISEASE: Bacterial fruit rot
HOST: Tomato
Fruit with uneven ripening and internal decay.

Bacterial fruit rot | Tomato
DISEASE: Bacterial fruit rot
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pseudomonas viridiflava
SOURCE: Y. Aysan
DISEASE: Bacterial fruit rot
HOST: Tomato
Fruit with external symptoms of water-soaking and translucence.

Bacterial fruit rot | Tomato
DISEASE: Bacterial fruit rot
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pseudomonas viridiflava
SOURCE: Y. Aysan
DISEASE: Bacterial leaf and stem necrosis
HOST: Watermelon
Seedlings with necrotic leaves and water-soaked stems.

Bacterial leaf and stem necrosis | Watermelon
DISEASE: Bacterial leaf and stem necrosis
HOST: Watermelon (Citrullus lanatus)
PATHOGEN: Pseudomonas viridiflava
SOURCE: Y. Aysan
DISEASE: Bacterial leaf scorch
HOST: Pecan
Pecan with necrotic scorched leaves with distinct dark lines between healthy and diseased tissues.

Bacterial leaf scorch | Pecan
DISEASE: Bacterial leaf scorch
HOST: Pecan (Carya illinoinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: T. Brenneman