DISEASE: Apple proliferation
HOST: Apple
Spring form of the adult black-veined psyllid, Cacopsylla melanoneura, a vector of apple proliferation. In winter, adults are more greenish in color.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Apple proliferation
HOST: Apple
Typical apple proliferation symptom of witches'-broom resulting from suppression of apical dominance and growth of dormant axillary buds. Branches are not usually bent down as shown here.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
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 stem rot
HOST: Dieffenbachia
Dieffenbachia with rot and decay of stem and leaf tissues.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: A. Alvarez
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Dieffenbachia with wilted and rotted leaves.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Cross section of stem exposing rotted tissues.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Leaf with rot and wilt.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Blister spot
HOST: Apple
Fruit with water-soaked spots.
Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr