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: Pear decline
HOST: Pear
Healthy pear shoot (left) and diseased shoots (center and right). Leaves are reddish and growth is stunted.

Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis)
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: S. Thomson
DISEASE: Pear decline
HOST: Pear
Close-up of infected pear branch showing premature reddish coloration of leaves and cupped, stunted leaves.

Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis)
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: S. Thomson
DISEASE: Pear decline
HOST: Pear
Reduced growth of infected trees in center of image.

Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis)
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: W. Sinclair
DISEASE: Pear decline
HOST: Pear
Psylla pyricola, the psyllid vector of pear decline phytoplasma.

Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis)
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: J. Clark, A. Purcell, M. Davis