DISEASE: Bacterial pocket
HOST: Beet
Sugar beets with many small tubercles at infection sites.

Bacterial pocket | Beet
DISEASE: Bacterial pocket
HOST: Beet (Beta vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. betlicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. betlicola
SOURCE: C. Schneider
DISEASE: Foamy canker
HOST: Almond
White, macerated tissues near cambium region is characteristic of disease. Foam is usually associated with cankers. The disease is suspected to be bacterial but the causal agent has not been identified.

Foamy canker | Almond
DISEASE: Foamy canker
HOST: Almond (Prunus dulcis)
PATHOGEN: Causal agent unknown
SOURCE: B. Teviotdale
DISEASE: Foamy canker
HOST: Almond
Amber red-colored ooze sliding down the trunk. The causal agent has not been identified.

Foamy canker | Almond
DISEASE: Foamy canker
HOST: Almond (Prunus dulcis)
PATHOGEN: Causal agent unknown
SOURCE: B. Teviotdale
DISEASE: Foamy canker
HOST: Koa
Foamy canker of koa is associated with bacteria and yeast. The causal agent has not been identified.

Foamy canker | Koa
DISEASE: Foamy canker
HOST: Koa (Acacia koa)
PATHOGEN: Causal agent unknown
SOURCE: H. Keyser
DISEASE: Foamy canker
HOST: Koa
Dieback of koa tree. The causal agent has not been identified.

Foamy canker | Koa
DISEASE: Foamy canker
HOST: Koa (Acacia koa)
PATHOGEN: Causal agent unknown
SOURCE: H. Keyser
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
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with brown, necrotic, blighted leaves.

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