DISEASE: Coffee leaf scorch
HOST: Coffee
Diseased twig with yellowish, stunted leaves (left). Healthy twig with normal-sized leaves (right).
Coffee leaf scorch | Coffee
DISEASE: Coffee leaf scorch
HOST: Coffee (Coffea arabica)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
DISEASE: Greasy center
HOST: Poinsettia
Stem with dark cankers and copious ooze. Necrotic areas are greasy in appearance and eventually turn light tan to brown with a papery texture as the cuticle becomes detached.
Greasy center | Poinsettia
DISEASE: Greasy center
HOST: Poinsettia (Euphorbia pulcherrima)
PATHOGEN: Pseudomonas viridiflava
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
DISEASE: Walnut blight
HOST: Walnut
Infected young shoots with black lesions.
Walnut blight | Walnut
DISEASE: Walnut blight
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Xanthomonas arboricola pv. juglandis
SOURCE: M. Schroth