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 (Brown stem)
HOST: Celery
Lesions are necrotic and circular to angular. Some have yellowish halos. Older lesions become brown and dry.
Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raid
DISEASE: Bacterial blight (Brown stem)
HOST: Celery
Ooze from lesion on celery leaf.
Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raid
DISEASE: Bacterial blight (Brown stem)
HOST: Celery
Characteristic brown discoloration of petioles, which is more evident on inside of petiole close to the crown. Parenchyma tissues are firm and brown.
Bacterial blight (Brown stem) | Celery
DISEASE: Bacterial blight (Brown stem)
HOST: Celery (Apium graveolens)
PATHOGEN: Pseudomonas cichorii
SOURCE: K. Pernezny
DISEASE: Bacterial blight
HOST: Cassava
Leaf with angular, water-soaked, vein-delimited lesions.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
DISEASE: Bacterial blight
HOST: Cassava
Cassava with angular leaf spots and yellow ooze. Symptoms include leaf spots, wilt, and dieback. The bacterium frequently invades systemically.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
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