DISEASE: Bacterial wilt
HOST: Grass
Initial symptom is a lime-green, yellow, or blue-green appearance of the grass. The next symptom is small, reddish brown spots on leaf blades.
Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: P. H. Dernoeden
DISEASE: Bacterial wilt
HOST: Grass
Infected turf grass with patches of yellowing, wilted, and dead grass.
Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Grass
Late stage of disease development. Dead grass has a light brown or bleached tan appearance.
Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Poa annua)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: P. H. Dernoeden
DISEASE: Brittle root
HOST: Horseradish
Dying, stunted, yellow to brown horseradish plants.
Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: C. Eastman, M. Davis
DISEASE: Brittle root
HOST: Horseradish
Close-up of stunted, yellow horseradish plants.
Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: D. Sherrod
DISEASE: Brittle root
HOST: Horseradish
Horseradish with discolored internal tissues. Healthy root segment (top right).
Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: J. Fletcher, M. Davis
DISEASE: Bunch disease
HOST: Walnut
Twisted shoot with yellow leaves, a symptom of bunch disease.
Bunch disease | Walnut
DISEASE: Bunch disease
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: E. Braun
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from longitudinal cracks in the trunk. Cankers are deep extending into wood.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from cracks in trunk, a result of systemic invasion by the bacterium.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale