DISEASE: Aster yellows
HOST: Aster
Foliar symptoms of chlorosis, malformation of leaves, and phyllody.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Flowers with phyllody (left and center). Healthy flower (right).
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Macrosteles sp., a leafhopper vector of aster yellows phytoplasma.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Clark, A. Purcell, M. Davis
DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.
Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial canker
HOST: Hazelnut
Primary symptoms are failure of buds to break and withering and death of new foliage in spring. Dead leaves remain attached to limbs after normal leaf fall.
Bacterial canker | Hazelnut
DISEASE: Bacterial canker
HOST: Hazelnut (Corylus americana)
PATHOGEN: Pseudomonas syringae pv. avellanae
PATHOGEN SYNONYM: Pseudomonas avellanae
SOURCE: P. Psalidas
DISEASE: Bacterial spot
HOST: Plum
Shot-hole phase of disease.
Bacterial spot | Plum
DISEASE: Bacterial spot
HOST: Plum (Prunus domestica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: T. Burr
DISEASE: Bacterial spot
HOST: Plum
Dark, sunken area on blossom end of fruit.
Bacterial spot | Plum
DISEASE: Bacterial spot
HOST: Plum (Prunus domestica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: S. Thomson
DISEASE: Bacterial spot
HOST: Plum
Dark brown necrotic lesions along main leaf vein. Lesions may drop off, leaving shot-hole effect.
Bacterial spot | Plum
DISEASE: Bacterial spot
HOST: Plum (Prunus domestica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: S. Thomson
DISEASE: Bacterial spot
HOST: Plum
Infected twig with small cankers.
Bacterial spot | Plum
DISEASE: Bacterial spot
HOST: Plum (Prunus salicina 'Friar')
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: J. Young