DISEASE: Bacterial leaf spot
HOST: Croton
Tan, irregular-sized lesions on lower leaf surfaces.
Bacterial leaf spot | Croton
DISEASE: Bacterial leaf spot
HOST: Croton (Codiaeum variegatum var. pictum)
PATHOGEN: Xanthomonas axonopodis pv. poinsettiicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. poinsettiicola
SOURCE: J. Yuen
DISEASE: Bacterial leaf spot
HOST: Crown-of-thorns
Leaves with brown lesions surrounded by bright yellow halos.
Bacterial leaf spot | Crown-of-thorns
DISEASE: Bacterial leaf spot
HOST: Crown-of-thorns (Euphorbia milii)
PATHOGEN: Xanthomonas axonopodis pv. poinsettiicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. poinsettiicola
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Poinsettia
Leaves with reddish brown blighted areas and spots. Severely spotted leaves turn yellow and dehisce.
Bacterial leaf spot | Poinsettia
DISEASE: Bacterial leaf spot
HOST: Poinsettia (Euphorbia pulcherrima)
PATHOGEN: Xanthomonas axonopodis pv. poinsettiicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. poinsettiicola
SOURCE: A. Chase
DISEASE: Bacterial leaf streak
HOST: Oat
Leaf with long, dark red streaks.
Bacterial leaf streak | Oat
DISEASE: Bacterial leaf streak
HOST: Oat (Avena sativa)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: L. Claflin
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: Crown gall
HOST: Grape
Grape with multiple galls on trunk resulting from systemic infection.
Crown gall | Grape
DISEASE: Crown gall
HOST: Grape (Vitis vinifera)
PATHOGEN: Agrobacterium vitis
PATHOGEN SYNONYM: Rhizobium vitus
SOURCE: H. Sawada, M. Goto
DISEASE: Crown gall
HOST: Grape
Multiple small galls on trunk of systemically infected grape.
Crown gall | Grape
DISEASE: Crown gall
HOST: Grape (Vitis vinifera)
PATHOGEN: Agrobacterium vitis
PATHOGEN SYNONYM: Rhizobium vitus
SOURCE: D. Gabriel
DISEASE: Crown gall
HOST: Grape
Gall on base of 'Zinfandel' grape in California, where aerial galls are less common because of dry, hot weather.
Crown gall | Grape
DISEASE: Crown gall
HOST: Grape (Vitis vinifera 'Zinfandel')
PATHOGEN: Agrobacterium vitis
PATHOGEN SYNONYM: Rhizobium vitus
SOURCE: M. Schroth