DISEASE: Bacterial brown rot
HOST: Orchid
Phalaenopsis orchid with yellowish brown spot on leaf (left), an early stage of disease.

Bacterial brown rot | Orchid
DISEASE: Bacterial brown rot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Acidovorax cattleyae
PATHOGEN SYNONYM: Acidovorax avenae subsp. cattleyae
SOURCE: R. McMillan
DISEASE: Bacterial brown rot
HOST: Orchid
Leaves of Phalaenopsis orchid with advanced stage of decay.

Bacterial brown rot | Orchid
DISEASE: Bacterial brown rot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Acidovorax cattleyae
PATHOGEN SYNONYM: Acidovorax avenae subsp. cattleyae
SOURCE: R. McMillan
DISEASE: Bacterial leaf spot
HOST: Orchid
Infected leaf of Phalaenopsis orchid with light brown necrotic area.

Bacterial leaf spot | Orchid
DISEASE: Bacterial leaf spot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Pectobacterium cypripedii
PATHOGEN SYNONYM: Erwinia cypripedii
SOURCE: R. McMillan
DISEASE: Bacterial leaf spot
HOST: Orchid
Diseased leaf of Phalaenopsis orchid with large, dark necrotic area.

Bacterial leaf spot | Orchid
DISEASE: Bacterial leaf spot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Acidovorax cattleyae
PATHOGEN SYNONYM: Acidovorax avenae subsp. cattleyae
SOURCE: R. Raabe
DISEASE: Bacterial soft rot
HOST: Orchid
Leaf of Phalaenopsis orchid with brownish rot and discoloration running up the midrib.

Bacterial soft rot | Orchid
DISEASE: Bacterial soft rot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: R. Raabe
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Lesions on leaves first appear as water-soaked, translucent, long, narrow streaks. They later turn brown and necrotic and often coalesce into blighted areas.

Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Close-up of leaf with brown necrotic streaks.

Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
X-disease causes undersized, yellowish fruit. Diseased branches turn rusty red near end of season. Some defoliation occurs on diseased branches.

X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus cerasus)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: A. Jones