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 and bacterial leaf streak
HOST: Rice
Xanthomonas oryzae pv. oryzicola (bacterial leaf streak) causes water-soaked streaks with yellow ooze (left side), and X. oryzae pv. oryzae (bacterial blight) causes brown streaks that have turned white (right side).

Bacterial blight and bacterial leaf streak | Rice
DISEASE: Bacterial blight and bacterial leaf streak
HOST: Rice (Oryza sativa)
PATHOGEN: Xanthomonas oryzae pv. oryzicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. oryzae
SOURCE: T. Mew
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
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Sycamore with scorched leaves and dieback of small branches.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Close-up of scorched leaves.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial leaf streak
HOST: Rice
Severely diseased leaves with light brown streaks.

Bacterial leaf streak | Rice
DISEASE: Bacterial leaf streak
HOST: Rice (Oryza sativa)
PATHOGEN: Xanthomonas oryzae pv. oryzicola
SOURCE: H. Kaku, M. Goto
DISEASE: Bacterial leaf streak
HOST: Rice
Brownish lesions with tiny droplets of bacterial ooze, resulting from artificial inoculation of the pathogen.

Bacterial leaf streak | Rice
DISEASE: Bacterial leaf streak
HOST: Rice (Oryza sativa)
PATHOGEN: Xanthomonas oryzae pv. oryzicola
SOURCE: H. Kaku, M. Goto