DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.

Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath)
Gall on gypsophila stem.

Gypsophila gall | Gypsophila (Baby's breath)
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath) (Gypsophila elegans)
PATHOGEN: Pantoea agglomerans pv. agglomerans
SOURCE: S. Manulis
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath)
Gall 1 month after inoculation of stem.

Gypsophila gall | Gypsophila (Baby's breath)
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath) (Gypsophila elegans)
PATHOGEN: Pantoea agglomerans pv. agglomerans
SOURCE: S. Manulis
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath)
Brown gall on crown of gypsophila.

Gypsophila gall | Gypsophila (Baby's breath)
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath) (Gypsophila elegans)
PATHOGEN: Pantoea agglomerans pv. agglomerans
SOURCE: S. Manulis
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath)
Galls (left) caused by Pantoea agglomerans pv. agglomerans tend to be brownish, and those (right) caused by P. agglomerans pv. betae are white.

Gypsophila gall | Gypsophila (Baby's breath)
DISEASE: Gypsophila gall
HOST: Gypsophila (Baby's breath) (Gypsophila elegans)
PATHOGEN: Pantoea agglomerans pv. agglomerans
SOURCE: S. Manulis
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