DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Wilted, stunted plants with yellowing foliage.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. P. Weingartner
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
External symptoms of the disease.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. Thurston
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Tubers with distinct grayish brown rings and bacterial ooze from vascular tissues.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: A. Hayward
DISEASE: Pierce's disease
HOST: Grape
Leaves with bright yellow, chlorotic areas with dead, dry, necrotic adjacent tissues.

Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylella fastidiosa
SOURCE: J. Clark, S. Purcell
DISEASE: Pierce's disease
HOST: Grape
Early symptoms of Pierce's disease on leaves. Symptoms vary greatly among cultivars.

Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: Xylella fastidiosa
SOURCE: J. Clark, S. Purcell
DISEASE: Pierce's disease
HOST: Grape
Late-season wood on diseased canes fail to mature, leaving green "islands" of tissue surrounded by dark brown, mature wood.

Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera 'Fiesta')
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
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