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 leaf blight and stalk rot
HOST: Corn (Maize)
Corn husk leaves with brownish red streaks and blotches. The leaves turn brown but may later become gray or white. Symptoms vary depending upon genotype.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: A. Alvarez
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize)
Leaves with whitish streaks.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize)
Lesions may vary from brown to red, sometimes gray or white, and some genotypes have red borders around lesions.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: R. Gitaitis
DISEASE: Xanthomonas leaf blight
HOST: Onion
This was the first photo of onion leaf blight, which was considered a controversial finding for 10 years until an outbreak occurred in the West Indies.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Diseased leaf with necrotic internal tissues.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez