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: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).
Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Walnut blight
HOST: Walnut
Typical symptoms of infected leaf and young nutlets. Infected young, growing leaves usually become malformed.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: M. Schroth
DISEASE: Walnut blight
HOST: Walnut
Tree with severely blighted foliage.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: M. Schroth
DISEASE: Walnut blight
HOST: Walnut
Nuts with side blight. Infections also are commonly found at stylar ends.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: B. Teviotdale
DISEASE: Walnut blight
HOST: Walnut
Nuts with decayed kernels.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: B. Teviotdale
DISEASE: Walnut blight
HOST: Walnut
Three catkins with different degrees of infection.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: M. Schroth